BASIC Level III (1983)

Operating manual for the John Sands Sega SC3000 Personal Computer John Sands ^50 I

I I V

BASIC LEVEL 10 Operator's Manual for the John Sands Sega SC-3000 Personal Computer John Sands SEGA

TABLE OF PREFACE 2 ^ Chapter 1. How to Handle the Computer 5 How to use the KEYBOARD 6 Special Key 12 Control Code 18 Chapter 2. Using the Computer 22 Direct Mode (direct command) 22 PRINT 23 Operation of the four rules of arithmetic 25 Operator 27 How to use (,) and (;) in PRINT statement 33 Chapter 3. How to Program 34 LET, Variables 35 String variables 39 CLS, LIST, NEW 40 INPUT, GOTO 44 END, STOP 47 FOR - TO, NEXT, STEP 48 IF - THEN, GOSUB 51 CONTENTS Table of Relative Operators 54 GOSUB, RETURN 54 ON GOTO 57 CURSOR 58 ON GOSUB 61 READ, DATA, RESTORE 62 DIM (Array) 64 ERASE 68 DELETE 68 AUTO 69 RENUM 70 SAVE, LOAD, VERIFY 71 REM 74 CONSOLE 74 Chapter 4. Functions 77 RND 77 INT 78 Character String Function 80 ASC (n") 80 CHR$ 82 LEFT$, RIGHT$, MID$, 83 LEN 84

STR$, VAL 85 TIMES 87 SPC , TAB 88 INKEYS 90 FRE 91 PRINTER Control Command 92 LLIST 92 LPRINT 93 HCOPY 93 Chapter 5. Graphics 94 SCREEN 95 COLOR 97 LINE 101 BLINE 102 PAINT 102 CIRCLE 104 BCIRCLE 108 PSET 109 PRESET 110 POSITION 110 PATTERN 113 How to draw Patterns 116 MAG 118 SPRITE 120 Chapter 6. Mathematical Function-2'" 123 SIN etc. 125 SGN 130 LOG 131 SQR 132 HEX$ 133 INP 134 DEF FN 134 BEEP 137 SOUND 138 OUT 139 POKE, PEEK, CALL 140 VPEEK 147 STICK (n) 149 STRIG (n) 149 APPENDIX 151 Variables and Arrays 151 Constant 152 Character code 154 Character set 156 Table of Command Statement 157 ERROR MESSAGE 162 Sample program 166

Published by John Sands Electronics Division of John Sands Limited 6 Bay Street Port Melbourne Victoria 3207 Australia Telephone (03) 645 3333 Telex AA 34206 First Edition 1983 Copyright (&> 1983 Sega Enterprises Ltd. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior written permission of Sega Enterprises Ltd. through John Sands Electronics. - -

BASIC LEVEL HI TEXT PREFACE The computer has now reached a level at which anyone can handle it with ease. What is a computer, then? Lets’s compare computers to stereos. COMPUTER •000=“® Cassette recorder External memory. STEREO L { CPU ) 1 Amplifier 1 Information is processed internally. KEYBOARD 1 Microphone Information (program) is entered from the outside. TV Monitor information (voice, music) is entered from the outside, Speaker Visually check CPU processing. Check CPU processing by listening. -2-

The above figure shows the computer mechanism. When information (program) is entered from the outside, results are displayed on the TV screen. Although there are various kinds of program languages available, the BASIC language is the most common language for personal computers. Some of the things we can do by using the BASIC language are: 1) Computing 2) Filing of statements and data. 3) Drawing of patterns and graphics. 4) Enjoying games and music. It is to your advantage to become familiar with the BASIC language so that you will be able to get the most out of your computer The term “language” sounds difficult, however, the BASIC language does not have too many commands to be remembered. You can write programs using only a few of these commands, and as you become more confident you can begin using more commands. Firstly, operate the keys while referring to the text. You will probably find some errors. Do not worry about errors, persevere, and continue to operate the keys. - 3 -

Very soon, you will find that the computer will become a most easy-going and reliable friend. - 4 -

Chapter 1. How to Handle the Computer First, read the instruction leaflet contained in the SC — 3000 unit. 1. Be sure that switch box is connected to the TV. (Where a TV with video input is used, directly connect the computer to the video input terminal and audio terminal). 2. Provide a switch box near the computer and select the TV channel, CH 3 or CH 4. 3. Select the proper channel shift switch of the computer, either CH 3 or CH 4, whichever is unoccupied. 4. Insert the BASIC cartridge correctly. - 5 -

5. After connections are complete, check the cable connections. If cable connections are correct, turn the TV power on. Then, also turn the computer power on. How to Use the KEYBOARD The KEYBOARD has keys on which letters, numerics, Dieresis characters ( foreign language ) and symbols are written. Some keys have 4 characters or displays. Example : /ffl 1 A Key layout and spacing are the same as in typewriters. So, you can push the keys with your fingers easily. Try to press the keys first. - 6 -

Push keys of / ffl 1 ^ I A and then Now, you should have 12 displayed on the screen. If you press keys by themselves the lower left characters or symbols written on the keys will be displayed on the screen. To display on the screen characters and symbols other than the above, use I SHIFT I key, I graph! key or I PIER’S I key. When I SHIFT I key is held down and then the screen. / ffl AA key is pressed ! appears on the - 7 -

GOTO GOSUB RETURN SCREEN POSITION COLOR LINE PSET SAVE" LOAD- VERIFY- AUTO RUN • POWER ' ffl 1 A 2'? « 3 g s m 4 E X a 5 E 8* ffl 6 E 1 • B 1 2 C ^ m 8 u ) 0 9 I 0 6 S-o "1 -la A Q ‘ S ¥ £ 1 ^ BREAK RESET - 8 -

CURSOR His blinking in the upper left portion of the screen. This is called the CURSOR and shows the position where characters and symbols which were entered from the keys are displayed. To move the CURSOR, use the 4 light grey keys with arrows on them. The type of the CURSOR varies depending on respective modes. Alphanumeric mode Dieresis mode Graphic mode - 9 -

Press I ENG/DIER’S I or I GRAPHi keys which are in the lower left hand side of the KEYBOARD. The CURSOR will change. To return the CURSOR to the original position from graphic mode, press the I GRAPHi key again. To display on the screen the characters and symbols which are written on the key surface, there are five methods available. 2 SHIFT + Alphanumerics 1 Alphanumerics 5 SHIFT + GRAPH Alphanumerics / ffl GRAPH Dieresis B A A GRAPH Dieresis SHIFT + Alphanumerics Alphanumerics } ] z Dieresis

I SHIFT I (Shift key) Right and left I SHIFT I keys work the same way. While holding down a I SHIFT I key, when the key with numerics is hit, the symbol to the top left of the key is entered. While holding down the I SHIFT I key, when an alphabetic character key is hit, a small letter is entered. I GRAPH~I (Graphic key) This is used to input graphic symbols. The CURSOR shifts to*. Graphic symbols may be used together with the I SHIFT I key. ENG DIER’S This is used when entering dieresis. Dieresis character can be typed while the Dier’s key is held down.

SPACE key (This allows space between characters and symbols) A i_j B 1—1 C When the space key is pressed once, the CURSOR moves to provide space corresponding to a character. The elongated key (in the bottom row) is the space key which inputs space(s) between characters and symbols. In computers, space is also handled as information, as in the case of characters. Input various characters using previously mentioned keys. Special Keys Now, you notice that the screen is full of characters and symbols which were previously entered by keys.

It’s no use leaving unwanted characters and symbols on the screen. We can clear the whole screen, using the following key. I HOME/CLR~l (Home/Clear) When this key is pressed, characters on the screen are erased and the CURSOR returns to the upper left “home” position. Use this key whenever you want to clear the screen. When I HOME/CLR I key is pressed while holding down the I SHIFT I key, the screen will remain uncleared but the CURSOR returns to the home position. I CR I (Carriage Return) or (Return) In computers, even if characters are on the screen these are not stored inside the computer until the I CR I key is pressed. Input any character and press the I CR I key. You notice a Syntax Error displayed on the screen. Instructions for computers need to be written a certain way. This is called the computer Syntax. If this Syntax is wrong, errors will occur.

For errors, refer to the error message table in the appendix. I INS/DELTI (Insert/Delete) The I INS/DEL I key is used when deleting or adding characters one by one. INS (Insert) refers to the addition of characters. del (Delete) refers to the deletion of characters. When @ [B] is typed by mistake instead of 0 [b] 0 the CURSOR will move backward by one character if the I INS/DFTTI key is pressed, and then character E is erased. Here, press D and a correction has been made to A B C D. Press I INS/DEL I key, and the CURSOR moves to the left by one space. Press key D. D enters. - 14 -

Now, let’s put any character in between the B and C of A B C D. Bring the CURSOR over the C of A B C D. While holding down the I SHIFT I key, press the I INS/DElTI key. You notice that the CURSOR blinks quicker than before. Input any character. The character which was entered just now enters after B and C D moves to the right by one character space. When the insert mode is used, as many characters as required can be entered (while the CURSOR is blinking quickly). When returning the insert mode to the original state : - 15 -

1 . Press I CR I key. 2. Press a CURSOR control key, (one of the light grey keys with arrows). 3. Press I SHIFT I + I INS/DET, I key. By pressing either one of the above keys, the normal condition is restored. When the program is corrected, the MEMORY inside cannot be rewritten unless the I CR I key is pressed. Confirm this by actually operating the keys. FUNC (Function) This key allows you to enter many of the common BASIC words with a single keystroke. The key has GOTO written on the upper part of it. Each key has alphabetic characters written on it. This is a command statement used in BASIC. While holding down the I FUNC I key, hit any key with a word above it, and the command statement written on the upper part of the key is entered. This is a useful feature when typing in programs. GOTO ./ ffl 1 X - 16 -

I ( V BREAK I (Screen shift/break) This is used for stopping programs during program run. The screen will change when IQ/ BREAK | key is pressed while holding down the I SHIFT I key, by pressing the keys again the screen ^ill change back. This is used for changing the screen, as the computer has two screens. One screen is text screen for entering programs, and the other, graphic screen for displaying graphics. i: J/break| { ) ^ This is used to shift screens. Use this while holding down I SHIFT I key. This is because the computer has 2 screens as mentioned above. BREAK # This is used for stopping program run while they are running.

I CTRL I (Control) Movement for which explanation is given below can be executed when the character key shown in the control key table is hit, while pressing the I CTRL I key. CONTROL CODE Key operation PRINT CHR$ (Value) Functions ICTRLI + [A] PRINT CHR$ (1) : NULL No character C BREAK Stops program run E 5 Clears Characters after CURSOR G 7 BELL Makes “beep” sound H 8 DEL Deletes characters 1 9 HT Horizontal TAB J 10 LF Line feed K 11 HM Returns CURSOR to home position L 12 CL Clears screen M 13 CR Carriage Return N 14 Dieresis <-> Alphanumeric shift 0 15 Screen shift, text graphic

Key operation PRINT CHR$ (Value) Functions P 16 Standard character size Q 17 Character size, horizontally 2 times as large (graphic) (Screen 2) R 18 INS (Insert) S 19 Key input (A~Z) no shift, capital letter T 20 Key input (a~z) no shift, small letter U 21 Clears lines and returns CURSOR to left head V 22 Normal mode W 23 GRAPH key input graphic mode <-> alphabetic character shift X 24 Click sound ON OFF shift - 28 CURSOR movement - 29 ^ CURSOR movement - 30 CURSOR movement - 31 CURSOR movement When the control code is used in the program, input PRINT CHR$.

I RESET I (Reset) During program run, or when problems appear on the screen, the screen returns to the situation as it was when the power was turned on within about 1 or 2 seconds after pressing the I RESET I key. When pressing this key, the computer stops processing and the size of the MEMORY which has not been used is displayed. XXX Bytes Free Even if the key is pressed, programs which were entered will remain in the memory. Now that you know how to use the keyboard, you should now be able to put any symbol on the dark grey keys onto the screen. 10 SCREEN 2,2:CLS | C R | 20 LINE (50,50)-(150,150),5 |C R I 90 GOTO 90 1 C R RUN I C R I RUN tells the computer to do what the program says. (For 0, press 0 in the top row. 0 is used for numeral 0 ) - 20 -

After typing one line, press the I CR I key. Entered programs are stored in the computer and the CURSOR moves on to the line below. Although using the keys may be difficult, try to hit character keys carefully one by one. This program 1 0 SCREEN 2,2 |CR| will continuously 2 0 C L S 1 C R 1 put a box on the 3 0 LINE ( 80, 100 ) - ( 150, 170 ) , C , BF screen changing 4 0 c = c + i rcTl the color of 5 0 IF C=1 6 THEN C=0 IXE] the box. 6 0 GOTO 2 0 IC R RUN To stop it push 1 ( VbreakI -21

Chapter 2. Using the Computer DJRECT MODE (Direct Command) This is to show you how to make the computer work without writing a program. Let’s try to print something on the screen. Ihome/clrI IIHUEDE Ispace I [I][l][s][I] |cr On the screen, the above will be displayed. - 22 -

ERROR is displayed because the computer cannot understand the command which was entered. Now, you want the computer to write BASIC TEST on the screen. To do this, give the computer a command to I PRINT I the character which was entered. The command for “write” is expressed as I PRINT I . To get the quotation mark " press this key while holding down a shift key. iHOME/CLRl [P] [R] dJ [N] E 0 ® Q] 0 |SPACE| PH [eI ^ HI H fc^ PRINT statement is a command statement for display on the screen. PRINT"BASIC test" -= Characters entered by the keys. BASIC TEST Characters which were output by PRINT Ready statement. Hopefully this time, no ERROR will be displayed because the computer understood what it was supposed to do. J When printing characters and symbols, use the PRINT statement. - 23 -

When telling the computer to print characters and symbols by PRINT statements, he sure to put " (double quotation marks) at the start and end of what you want printed. Now, PRINT your name. Use alphabetic characters or Dieresis characters. All the numerics, symbols and graphic symbols can also be entered in " " . Spaces in " " are printed too. Press the space key once. (In this case, press it 5 times.) [E0LDE1E '' LijL_IL_ll_JL_J lI]0[I][I][3L_IL_.L_IL_l[T][l][S][t] " I II II I I I I I BASIC I II II II I TEST Ready This means space for one character. PRINT statement is a command statement very often used in programming to show what the computer has been doing.

For numbers and equations the above quotation marks are unnecessary, eg. PRINT 3,3*4. Now, try printing in a different way. E [U S S I C R I ? Can be used instead of PRINT . 6 Ready We gave the computer a command to calculate 2+4 and then PRINT the answer. Let the computer display the calculation results also by a PRINT statement. Symbol ? is a shortened form of PRINT statement. This is true of most personal computers. OPERATION OF THE FOUR RULES OF ARITHMETIC. In computing, some of the symbols used are different from those normally used. - 25 -

Symbol used in the computer Normal Symbols Addition + Plus + Subtraction — Minus — Multiplication =1= Asterisk >1 Division / Slash Raising to Power A X" A symbol used in computing is called OPERATOR. Other than the operator, parentheses ( ) (brackets) are also used in numerical expressions. RELATIVE OPERATOR is used for the comparison of numeric values (numeric magnitude). The following table summarizes the above. Be sure to read the table before application. - 26 -

Operator Where usable Symbol Numeric variable String variable Description Priority A O X Power (0 A 0 = 1) 1 C3 + O X Code + 2 O cOu 0) - O X Code — * o X Multiplication 3 o o / o X Division CD a iM< MOD o X Residual 4 + o o Addition (Character combination in case of string variables) 5 - o X Subtraction • ( ) is given the first priority. • Where more than 2 operators with the same priority are used, the left side operator takes precedence. • An addition symbol “+” used for string variables shows a linkage. (Example) “AB” + “C” ^ “ABC” Arithmetic operation is decimalized. (Example) : Even with values of 0.01, no cancelling in digit occurs. Logical operation is binary. Arithmetic operation : Decimal 12 digit calculation, 11 digit display. - 27 -

Notice symbol O in the lower right-hand side of the KEYBOARD. This is a graphic symbol and unusable for calculations. Kef's try calculating again. PR I N T 5 *6 30 t Where the answer is positive (plus), symbol + is omitted, resulting in one empty character space. - 28 -

For PRINT, P R I N T 1 0 / 3 3.3333333333 PRINT I FUNC I key and can also be used to make it easier. ?INT((3A4)+0.1 ) I C R I means (3x3x3x3) 8 1 Operation functions allow highly accurate decimal calcualations with 11 digit display. 7 1 0 0 0 0 0 0*1 0000 I C R I 1 0000000000 11 digits 7 10/3 3.3333333333 10th decimal place For numbers greater or smaller than the above, the scientific notation system is used. 7 1 938000000*1 0000000 1.938E + 16 (1. 938X 1 0‘M - 29 -

Calculation priority ? 6 + 2*4 In calculations in which two numerical expressions are contained, are the calculations done from the beginning position ? Priority applies to the four rules of arithmetic. Priority is as shown in the table of operators. Let’s run through an example again. ? 6 + 2*4 1 4 Note that calculation for multiplication is done first. For calculating addition first, use ( ). ? ( 6 + 2 ) *4 3 2 When addition, subtraction, multiplication and division are involved in the formula in one line, use ( ) for the expression to be calculated first. ( ) can be multiply used more than once in an equation, but brackets and braces as in mathematics are not used. Only parentheses are used. - 30 -

® ® (3) (2) ? 3 *(( 8 + 6 )/( 4 - 2 )) 2 1 Calculations of the above example are done in the order of the sequence number given. If the priority is the same, calculation starts from the left side expression. When using parentheses, the number of the left side parentheses and that of the right side parentheses need to be the same. If the number is not the same, errors will occur. Be sure to check the number of parentheses. ANOTHER WAY TO USE THE PRINT STATEMENT. At the beginning of this chapter we printed letters or symbols enclosed by " " . When this is used in the calculation formula, what will happen ? ? " 2 + 3 = 2 + 3 = 5 Be sure to insert this. ; 2 + 3 -31 -

Previously, only the answer was displayed. But this time, the equation was also displayed. The upper formula of the above is the combination of two statements. " 2+3 " = was handled as characters and not as a calculation formula. Thus, it is displayed as it is. After breaking by ; (semicolon), the statement thereafter was handled as a formula of 2+3, and thus, the answer was displayed. Another example : ? " 2 + 3 = " , 2 + 3 2 + 3= 5 Ready The answer is given far apart on the screen. When a comma, (,) is used, the answer displayed is found in the position 20 digits away from the end of the screen. When using PRINT statement, pleasing displays can be obtained by properly using semicolon and comma. - 32 -

How to use (,) and (;) in PRINT statement. So far, you have learned how to make the computer do arithmetic. Notice that the equal ( = ) symbols which is normally used in mathematics is not displayed in the calculation formula. In computers, symbols are used in a different way. This will be explained in the next chapter. How to Program. -33

Chapter 3. How to Program Let’s generate programs by using BASIC. Programs which were entered from the KEYBOARD are stored into the MEMORY inside the computer. The computer works from the smallest line number to the greatest line number. After line number, there are statements to let the computer know how to perform its task. LET (Example) 1 0 [cTI 2 0 BBS [UB® |CR| 3 0 B[e]E EHHS® |CR| 4 0 BBBBB B [m 5 0 BBB |cr| -34

EE]® [c^ 8 Ready A new statement RUN is displayed. This is a command statement to make the computer do whatever the program tells it to. LET , VARIABLES LET (substitution statement) is a command statement used for giving a number value for a variable. 10 LET A=3 The above A could be thought of as an empty box called A. We call this box a variable. This expression doesn’t mean that A equals 3. It means putting the number 3 in Box A. The LET statement is optional. Therefore, the following can be entered. 1 0 A = 3 - 35 -

For the following, LET is also omissible. 30 LET C=A+B Symbol equals (=) doesn’t mean to be equal, but refers to putting a number in a certain place. =5 VARIABLE / A = 5 Input 5 in A. = A+B VARIABLE C = A + B ^ A + B -1 + 1 - Input A + B in C. rx VARIABLE VARIABLE + 1 X = X + 1 - 36 - Substitute the result of X + 1 for variable X.

c $ = VARIABLE = " ABC " ABC " Substitute string ABC in C$. D $ = " DEF " Substitute DEF for D$. E$=C$+D$ Substitute ABC + DEF for E$. Substitution statement can be used as follows. X = X+ 1 This is not true mathematically, but qenerally used in the substitution statement.

Example 1 0 2 0 3 0 4 0 RUN 1 C L S X = X + 1 PRINT GOTO 2 3 4 X 2 0 5 Line No. 6 7 8 . . . Numbers consecutively appear every other character. X starts with 0. (0) (0) With X = X + 1 , 1 is substituted for the left side X. (i) After jumping from line No. 40 to No. 20, RUN returns to X = X + 1 and with 1 added to X, the left side X becomes 2. In computers, the above-mentioned applications are often adopted. - 38 -

String variables Attach $ (dollar) mark to string variables. 1 0 A = 3 2 0 B = 5 3 0 C = A+ B 4 0 M $ = " ANSWER 50 PRINT M$:C RUN ANSWER 8 Ready 4 0 M$ = "ANSWER represents space Provide one empty character space by the space key. In this way, a character string " ANSWER " was entered in box M$. For a character string, the left and right side of the character needs to be enclosed by double quotation marks ( " ). If this is not done errors will occur. Numerics or graphic symbols can be used for string variables. Furthermore, two string variables can be connected. - 39 -

Provide one character space. 1 2 3 4 5 R I 0 A $ 0 B $ 0 C $ 0 PR 0 E N U N AM A BOY Ready jHHj CIS, LIST, NEW Various statements are available for BASIC. At the time of RUN, programs remaining on the screen may be confusing. If a command for screen erasure is entered in the beginning of a program in advance, all displays on the screen are erased at the time of RUN. Input new statements in the current program. CLS 5 CLS •— command to erase screen display. - 40 -

Enter line No. 5 CLS below the program which was previoulsy entered, in a place where there is no writing. . Program input from line No. 1 to 65535 is possible. If programs are generated with closely arrayed line numbers (e.g. 1,2,3,), additions between programs which were previously entered are impossible. Therefore, it is common practice to go up by 10 for each line number so that lines can be put in between other lines without difficulty. Where programs are entered up to line No. 100 (going up by 10), even if unused line numbers such as 25 and 55 are entered after line No. 100, these numbers can be rearranged by the computer internally. Lets check the outcome of the entering of the above-mentioned 5 CLS. LIST Enter |H0ME/CL^ LIST | C R | 5 CLS 1 0 A $ = II j II 2 0 B $ = "AM " 3 0 C $ = "A BOY" 4 0 P R 1 NT A$-t-B$ + C$ 5 0 END -41 -

Note that line No. 5 is entered at the beginning. Now, start run. LIST is a command statement to make the computer display programs which were entered. How to use LIST is as follows. LIST commands are used as follows : LIST LIST LINE NO. LIST LINE NO. - LINE NO. Displays the entire contents of programs. Only one line is displayed. Line No. to line No. is displayed. - 42 -

LIST LINE NO. - The content of programs after line No. is displayed. LIST - LINE NO. This displays from the beginning of the program to line No. The content of the program displayed by LIST statement can be rewritten using the CURSOR. LIST 30 30 C$="A BOY" Move the CURSOR to the place above B and input M. Subsequently, input AN and press I CR I . After rewriting the content of the program, be sure to press the I CR I key. If you forget to press the I CR I key, the content of MEMORY does not change even if characters on the screen do. When the 1 SPACE"! key is pressed during the list display, the list display is halted. For immediate correction of the program, press the I BREAKj key. When the I SPACE I key is pressed during LIST display, the display restarts. NEW When entering a new program after finishing one program, if the preceding program remains intact in the MEMORY, the new program may not work normally. - 43 -

The program which was previously entered cannot be erased by CLS statement from the inside of the MEMORY. To erase programs, input NEW and press I CR I . ' Let’s display LIST. LIST I C R Ready Nothing is displayed. All programs were deleted from the MEMORY. From explanations given so far, you have learnt something about computer programs. While entering programs, errors in typing and statements may occur until you become familiar with programming. When starting RUN with such errors remaining, execution stops at the line No. which has such errors. This sort of an error is called a BUG. As you know, BUG refers to insects. So, this is called a worm-eating problem. Thus, correction of this is called DEBUG. Although BUG finding is easy with a short program, it is not so with a lengthy program. So, be careful when entering programs. INPUT, GOTO Let’s write calculation programs. - 44 -

In the calculation program written at the beginning, the values of variables were set in the program, so numbers to be calculated had to be corrected each time. ' Let’s write calculation programs which are consecutively usable. 1 0 2 0 3 0 4 0 5 0 6 0 R U C L S INPUT INPUT B C =A + B PRINT C _ GOTO 20 ^ Line No. to which execution jumps. N |C R I -45

(WAITING FOR INPUT A) (WAITING FOR INPUT B) [4] I C R I INPUT 4 d] I C R I - INPUT 5 ?Bd] I C R I ?B0 I c R 1 5 ? H Here, press I BREAKi key. BREAK IN 20 RUN was stopped at Ready line No. 20. GOTO When computer’s operation flow encounters GOTO statements, RUN unconditionally jumps to the assigned line No. This program returns to line No. 20 from line No. 60 and restarts from INPUT A. This sort of program is repeated endlessly and thus it’s called an infinite loop. The only way the program is stopped is by the I BREAK 1 key. - 46 -

When the program flow encounters INPUT statement, values are entered in variables from the KEYBOARD and the flow is halted until the I CR I key is pressed. INPUT statement is also applicable to string variables. Comments enclosed by " " can also be displayed, as in PRINT statements. C N N EW 10 CIS 2 0 INPUT" NAME ?l_i" 1 A $ 30 PRINT A$ 4 0 END RUN NAME ? HANAKO ^ Input character HANAKO Ready / END, STOP END informs you of the program end. STOP halts program flow.

CONT This is used when restarting the program which was interrupted by STOP statement and the I BREAK I key. 10 X=X+ 1 20 PRINT X 30 GOTO 10 Run this program, and halt run during operation by the I BREAK"! key. Break in 20 CONT I C R I In this way, the program restarts from the position the program was halted. FOR - TO, NEXT, STEP These are used to make the computer do its work repeatedly for a specific number of times. - 48 -

Repeats 10 times. 10 C L S 20 FOR N=0 TO 9 30 PRINT N 40 NEXT N 5 0 END FOR — TO is used together with NEXT as a pair. In this program, N increases one by one from 0 to 9. 10 CIS 20 FOR N=0 TO 20 STEP 2 3 0 PRINT N ; 40 NEXT N 5 0 END RUN 0 2 4 6 8 10 12 14 16 18 20 With step 2, increases from 0 to 20 take place by an increment of 2. The ~ (minus) symbol can also be used for STEP. Let’s change line No. 20. - 49 -

0 S T E P - 2 2 0 FOR RUN N = 20 T 0 2 0 18 1 6 1 4 1 2 1 0 8 6 4 2 0 From 20, decreases take place by an increment of 2. In this way, STEP is used when increasing or decreasing a specific number at one time. FOR — NEXT statements can be nested. 1 0 C L S 2 0 FOR A= 1 TO 9 3 0 FOR B = 1 TO 9 n ^ 4 0 PRINT A * B : B loop 5 0 NEXT B 6 0 PRINT 7 0 NEXT A A loop The multiple use of FOR — NEXT statement is called “nesting”. Multiple nesting up to 16 levels is possible. If the specified nesting is exceeded, nesting errors will occur. Variables such as FOR I = 1 TO N can also be used. - 50 -

1 0 C L S 2 0 FOR N = 1 TO 2 0 — 3 0 FOR M= 1 TO N 1 '1 Group 4 0 P R 1 N T " 0 " ; M Group 5 0 NEXT M 1 Correct way of usage 6 0 PRINT 7 0 NEXT N Cautions for nesting FOR N=1 TO 20 FOR M=1 TO 10 NEXT N NEXT M Incorrect way of usage FOR, NEXT groups cannot be intersected. IF - THEN, GOSUB Program flow sequentially proceeds from the side with the smallest number. When reaching a given situation, let’s try to change the flow. -51 -

(“ACCEPTABLE” OR “UNACCEPTABLE” PROGRAM) 1 0 c L S 2 0 1 N P U T II SCORE " : A 3 0 1 F A > = 6 5 THEN G 0 S U B 1 0 0 4 0 1 F A < = 6 5 THEN G 0 S U B o CM 0 5 0 G 0 T 0 2 0 1 0 0 P R 1 N T " ACCEPTABLE 1 1 0 R E T U R N 2 0 0 P R 1 N T " UNACCEPTABLE 2 1 0 R E T U R N IF — THEN is a command to analyze a situation. The above program analyzes the SCORE entered by INPUT statement, evaluating by IF statement and changes the program flow. If the score entered is more than 65 points, the program goes to line No. 100 by GOSUB statement. If it is less than 65 points, operation goes to line No. 200. IF A>=65 THEN GOSUB 100 This statement means : IF A is greater than 65, THEN, jump to the subroutine beginning at line No. 100 and return. Following IF — THEN, statements other than line No. can also be used. - 52 -

(Omissible) F ~T H E N 0 T 0 LINE NO. (Jumps to the assigned line No.) F~T H E N G 0 S U B LINE NO. (Jumps to the assigned line No.) F ~T H E N PRINT" X X X " (Enters on the screen) F~T H E N END (Ends program) F~T H E N STOP (Stops program run) F~T H E N BEEP - (Produces sound) To analyze a situation, use relative operators shown in the table below.

Table of Relative Operators Symbol Description .2 ’-tj = Equal to ( —1 for true, 0 for false ) cd !D < > Not equal to ( —1 for true, 0 for false ) o > Greater than ( —1 for true, 0 for false ) > < Less than ( —1 for true, 0 for false ) cd > = Greater than or equal to ( —1 for true, 0 for false ) Ph < = Less than or equal to ( —1 for true, 0 for false ) C NOT Logical denial ^ o cd 'Xs AND Logical product fcuO 0) n OR Logical sum hP O XOR Exclusive OR GOSUB, RETURN The preceding program had a GOSUB statement. With GOTO statements, the program only goes to the assigned line No. GOSUB statement, however, is used together with RETURN statement. After jumping to the assigned No., operation returns to the line following GOSUB statement by RETURN statement. - 54 -

2 0 1 N P U T A 3 0 1 F A > = 6 5 THEN GO 4 0 1 F A < 6 5 THEN G 0 S 5 0 GO T 0 2 0 1 0 0 P R 1 N T II ACCEPTABLE 1 1 0 R E T U R N 2 0 0 P R 1 N T II UNACCEPTABLE 2 1 0 R E T U R N When using GOSUB statement, errors will occur if you forget to enter RETURN STATEMENT. After operation’s returning by the RETURN statement, the program proceeds from the line following GOSUB. So, change the program flow again as in the case of line No. 50. Where the program branches midway through, a flow chart is prepared so that the program flow can be easily understood. - 55 -

In the flow chart, the flow proceeds from the top downwards. The flow changes by the situation analyzing statement. When generating complicated programs, the flow can be clearly understood by preparing the flow chart. - 56 -

ON GOTO ON GOTO statement is used similiar to the conditional statement. ON A GOTO 100,200,300 Where variable A is 1, the program jumps to line No. 100. Where variable A is 2, it jumps to line No. 200. The values of variables corresponding to the number of line No. following GOTO statement can be used. (For A, input values 1~3) 10 INPUT " ORDER ; A 20 ON A GOTO 100,200, 3 0 0 100 PRINT "COFFEE " : G 0 T 0 1 0 200 PRINT " CAKE : G 0 T 0 1 0 300 PRINT " MILK " : G 0 T 0 (COLON) 1 0 More than 2 command statements can be entered in one line ( multi -statement). When entering more than one independent statement in one line, break them by : (colon). - 57 -

Key input RUN ORDER COFFEE ORDER CAKE ORDER MILK ORDER HU I B R E A K I Ready ON GOSUB is also used in the same way. Before giving you an explanation, let’s use the new command statements. CURSOR Previously, at the time of RUN, you had displays only on the left side of the screen. If programming is done so as to have displays in specific positions on the screen, you can see displays more easily. The CURSOR statement is a statement to define the display positions. - 58 -

The text screen on which the program is written consists of 912 locations formed by 38 digits X 24 lines. CURSOR 18,12 :PRINT"A" If you enter it directly without using line number, you will notice that character A is displayed in the central position on the screen. - 59 -

When using the CURSOR statement on the graphic screen: X axis direction 0 ~ 255 ( 256 dots ) y axis direction 0 — 191 ( 192 dots ) The beginning position of characters you want to display is defined if coordinates are assigned by the CURSOR statement. - 60 -

ON GOSUB 1 0 C L S 2 0 CURSOR 1 0 3 P R 1 N T " MENU 3 0 CURSOR 1 0 6 P R 1 N T II 1 . . DRINK" 4 0 CURSOR 1 0 8 : P R 1 N T II 2 . . . FOOD" 5 0 CURSOR 1 0 1 0 : P R 1 N T " 3 . . . DESSERT" 6 0 CURSOR 1 0 1 3 : 1 N P U T ' ORDER " ; A 7 0 ON A GOSUB 1 0 0 ,2 0 0, 3 0 0 8 0 GOTO 60 1— Erase previous display 1 0 0 CURSOR 1 0 , 1 6 : P R 1 N T It 1 1 0 CURSOR 1 0 1 6 : P R 1 N T COFFEE . . . $3.00 " 1 2 0 RETURN 2 0 0 CURSOR 1 0 1 6 : P R 1 N T II 2 1 0 CURSOR 1 0 1 6 : P R 1 N T CAKE ... $ 2.00 2 2 0 RETURN 3 0 0 CURSOR 1 0 1 6 : P R 1 N T " 3 1 0 CURSOR 1 0 1 6 : P R 1 N T MELON . . . $2.50 " 3 2 0 RETURN

ON GOSUB is a form varied from the program with GOTO. Although only the CURSOR statements are used, displays are in the central positions. So, you can notice displays more easily. When using GOSUB, don't forget to enter RETURN. READ, DATA, RESTORE Data previously entered in the program can be read by READ Statement. 10 READ A,B,C,D 20 PRINT A+B+C+D 100 DATA 1,2, 3, 4 RUN 1 0 Ready The numeric values of DATA were added to display the result. You can also enter string variables by using READ and DATA statements. - 62 -

When encountering READ statement, the program flow reads the DATA statement first wherever the statement may be. , C $ , D $ $ + C $ + D $ 10 READ A$,B$ 20 PRINT A$+B 30 DATA S,E 40 PRINT 50 DATA G 60 DATA A RUN SEGA Provides space for one line. Ready Where string variables were used, even if numerics are entered in DATA, these numerics are handled as characters and unusable in mathematical calculations. The number of DATA and that of READ statement variables need to be the same. - 63 -

When the number of DATA is more than that read, only the DATA corresponding to the variables of READ statement will be displayed. Where the variables of READ statement exceed the DATA, errors will occur. When the same data is used repeatedly from the beginning, use RESTORE statement. RESTORE 1 0 R E A D A , B ,, C , D 2 0 D A T A 1 , 2 , 3,4 3 0 R E S T 0 R E 4 0 R E A D E - Reads the beginning data 1. 5 0 P R 1 N T A+B+C+D+E R U N 1 1 DIM (array) 1 — Dimensional Array In the previous program, variables A, B, C and D were used for the DATA. As the number of DATA increases, it becomes more troublesome to set variables one by one. - 64 -

In such a case, arrays are used. DIM A (5) <— Value in ( ) is called a subscript. This means that six variables A(0), A(l), A(2), A(3), A(4) and A(5) were dimensioned. String variables can also be dimensioned. 1 2 3 4 5 6 7 1 1 0 C L S 0 DIM A$(5),B(5) 0 FOR 1=0 TO 5 0 READ A $ ( I ) , B ( I ) 0 PRINT A $ ( I ) , B ( I ) 0 PRINT To provide one line Space 0 N E X T I 0 0 DATA COFFEE, 2 5 0, MILK, 1 5 0, CAKE, 20 0 1 0 DATA TEA, 2 8 0, TOAST, 18 0, BREAD, 100 Although DIMA $ (5) was entered, READ statement refers to A $ (1). This is because I is the one used in FOR I = 0 to 5. Thus, while I changes from 0 to 5, DATA is read.

In READ statement, DATA alternatively array string variables and numeric values since A $ and B are consecutively read. Let’s experiment to array the DATA. 2- Dimensional Array In 2 - Dimensional array, subscripts in ( ) are divided into two parts, for example, DIMA (9 , 9). Multiplication Table 10 C L S 2 0 DIM A ( 9 , 9 ) 30 FOR J=1 TO 9 40 FOR K=1 TO 9 50 A(J,K)=J*K 60 PRINT A(J,K); 70 NEXT K 80 PRINT -^To change line 90 NEXT J RUN - 66 -

1 2 3 4 5 6 7 8 9 2 4 6 8 1 0 1 2 1 4 1 6 1 8 3 6 9 1 2 1 5 1 8 2 1 2 4 2 7 4 8 1 2 1 6 2 0 2 4 2 8 3 2 3 6 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 6 1 2 1 8 2 4 3 0 3 6 4 2 4 8 5 4 7 1 4 2 1 2 8 3 5 4 2 4 9 5 6 6 3 8 1 6 2 4 3 2 4 0 4 8 5 6 6 4 7 2 9 1 8 Dimensional Array 2 7 3 6 4 5 5 4 6 3 7 2 8 1 DIM A ( 5 , 5 , 5 ) Array declaration is possible up to 3—Dimensions. If no array declaration is given by DIM statement, the subscript with the maximum value of 10 is automatically applicable to the declaration. - 67 -

ERASE This is used to make array declaration invalid during program run. When 100 ERASE is entered, all the arrays in the program will become invalid. Where array name such as 100 ERASE A, B$ is entered, the array will become invalid. DELETE DELETE statement is used to delete unwanted lines when correcting programs. r DELETE 180 220 | C R | , (comma) may be used instead of — sign. Line numbers 180 -220 are deleted by the above. DELETE DELETE DELETE — 2 5 0 Deletes programs from the beginning to line No. 250. 6 0 0 — Deletes all numbers from No. 600 onwards. 10 0 Deletes line No. 100 only. - 68 -

So far, some of the BASIC statements have been used. When programming, be sure to enter the line number. The following shows the statement which automatically generates the line number. AUTO Enter AUTO I CR I without line No. 1 0 I C R I 2 0 Line numbers are automatically generated by STEP 10. AUTO 100 C R 1 0 0 1 1 0 C R Note that the line numbers are displayed starting from No. 100 by STEP 10. - 69 -

A U T 0 , 1 0 , 2 0 [TT| (Starting line No. and STEP number) 1 0 I C R 3 0 I C R I 5 0 Each time I CR I key is pressed, line No. is displayed by STEP 20. RENUM (Renumber) When line numbers are too closely arranged while the program is entered and line numbers are added, RENUM is used to renumber line Nos. RENUM I C R I Line numbers are renumbered from the beginning of the program in the order of 10 , 20 , 30 and so on. RENUM 100 I C R I Correction is made by renumbering with step 10 starting from line No. 100. - 70 -

R E N UM 300 , 200 I I New No. Previous No. The program is renumbered by step 10 starting from the previous line No. 200 which is to be renumbered as line No. 300 R E N UM 300 , 200 , 50 Step assignment Renumbering with step 50 starts from line No. 300. SAVE, LOAD, VERIFY SAVE SAVE allows the recording of generated programs, data, etc. in the cassette tape. -7 1-

Enter the file name. S A V E " X X X X " I C R I Saving — Start ^ When display is on the screen, press the recording button of the audio cassette. Saving, End <— This refers to the end of the recording. At this time the cassette is to be stopped. Use the file name so that the program content is easily understandable. For naming, use no more than 16 characters. If you have a cassette deck available, use it. If the cassette deck has a counter provided, write the counter number on the cassette tape label. VERIFY Whether or not SAVE was done accurately is checked by the VERIFY statement. Rewind the tape, input I CR I and press the play button. If accurately saved, VERIFY OK will be displayed. If VERIFY OK is not displayed, repeat SAVE from the beginning. - 72 -

LOAD Shift the program data in the cassette tape to the computer. LOAD Program name. XXX" [FrI Loading Start ^ Press play button. Found " X X X " Loading End Stop cassette. When using your cassette deck, writing or reading may be impossible depending on the sound level. This does not mean computer trouble but sometimes results from cassette deck performance. Try to change the levels of sound volume and quality. If writing is still impossible, use a cassette deck compatible with the computer. For connection to the cassette tape recorder, use the mini—plug available on the market. SC - 3000 side Cassette recorder side IN « LOAD , VERIFY ^ Earphone (EAR) OUT SAVE ^ Microphone (MIC) - 73 -

REM When generating programs, it is convenient to prepare the remark statement in advance so that details of the program or subroutine can easily be understood by looking at the program list later. 10 REM XXX CALCULATION x x x 2 0 C L S 30 PRINT 2+3 I The REM statement in the program is ignored and not executed. CONSOLE This assigns the scroll range of the text screen, ON/OFF of click sound as well as the shifting from capitals to small letters or vice versa. - 74 -

Scroll range assignment V L C S 0 , 1 y 0 i 4 24 Scroll range (from 5th to 15th lines) Where the sum of V and L exceeds 23, errors occur. CONSOLE 5 , 15 , V ; Upper limit of scroll (0~22) L ; Length of scroll (2~24) C ; Presence of click sound 0 : Not present 1 : Present S ; Size of Alphanumerics 0 : Capital w/o shift 1 : Small w/o shift The screen is divided by lines 0~23 in the direction of y. The numbers after CONSOLE show the starting and ending lines of scroll. If the scroll range is assigned as shown in the above example, the CURSOR moves within the range between the 5th and 15th lines. Set the CURSOR moving range to 0~23. If the highest number of the set range is 24 or more, errors will occur. The scroll length can be from 2 to 24 (the upper limit set number). - 75 -

The third numeric of CONSOLE,, 0, refers to whether or not the CURSOR is set so as to produce a click sound at the time the key was pressed. 0 ; No sound 1 ; Makes sound The 4th numeric of CONSOLE,,, 1 defines the capital or small alphabetical characters. 0 ; Capital letters w/o shift 1 ; Small letters w/o shift For omitting the 4 numerics, input only (,). The CONSOLE statement can be cleared by the RESET key. - 76 -

Chapter 4. Functions In the function group, there are mathematical functions and string functions. Be sure to remember functions which are frequently used. R N D ( Random number ) This function is used to have the values of variables generated at random. This is frequently used, being useful in simulating dice rolls, and irregularly moving games and targets. RND (1) Random numbers between zero and one. RND (0) The previous random number will be given. RND (-1) Random number generation pattern is reset. Let's generate random numbers. 1 0 FOR N = 0 2 0 R = R N D ( 1 ) 3 0 P R 1 N T R - 77 -

40 NEXT N RUN . 2380546294 . 7041 382496 .4925371138 i Numbers from 0 to 1 are generated at random. These are random numbers. If numbers which appear next are predictable, these cannot be called random numbers. What is interesting is that until you cast dice you can't tell what the result will be. Decimal fractions are not practical. The random numbers are arranged as follows to allow you to use them more easily. I NT (n) (integer) INT functions convert real decimal numbers into integers. ? I N T ( 3. 1 4 ) C R I 3 ^ Decimal numbers are erased. Ready - 78 -

DICE 10 FOR N=0 TO 20 20 S=INT(RND(1)>1<6) 3 0 PRINT S ; 40 NEXT N RUN 3 5 0 4 1 5 0 Decimal points have disappeared. While 0 exists, 6 doesn't. This is not applicable for dice. Let's correct it. n— To eliminate 0 and insure 20 S=INT(RNDC1 )^6) + 1 necessary numbers. ^ ' The number wanted. Now, this time, numbers from 1 to 6 appear. Try in different ways by changing numerals. Program for rounding to the nearest whole number. 10 INPUT A ^ Value with decimal fractions 20 PRINT INT(A+0.5) 30 GOTO 10 - 79 -

This is the program in which decimal fractions are rounded to the nearest whole number. The program is applicable to various calculations. Be sure to keep this in mind. CHARACTER STRING FUNCTION More explanation about string variables is given here. String variables are also called character string variables. In other text books, the term of string variables is used. Let's see how characters are handled in computers. ASC ( " N " ) (ASCII Functions) ASCII refers to American Standard Code Information Interchange which with numbered characters and symbols allows computers to process information with ease. Now, let's try this one. ? A S C ( " A " ) 6 5 Ready C R I ( Run by direct mode ) - 80 -

The above number 65 represents A. When using ASC statements, enclose the character in ( ) by " " as in ( " A " ). Now try to enter a symbol in ( ), instead of A. ? ASC { " ! " ) Now, 33 is displayed. In the inside of the computer, characters and symbols on the KEYBOARD are entered, corresponding to numbers from No. 32 to No. 255. Unlike humans, computers are unable to understand characters as they are. In computers, all characters are handled as numerics. Thus, characters are classifiable on an understanding that A (65) precedes B (66). Even if more than two characters enclosed in ( ) are entered as in ? ASC ( BA ) the computer checks only the first character and displays the numeric. Let's try another one. 10 INPUT A $ 20 Q=ASC(A$) 30 PRINT Q 40 GOTO 10 After RUN, when characters and symbols are entered, corresponding code numbers are displayed.

CHR $ This is the opposite of ASC statement and gives control functions for variables and characters. ? C H R $ ( 6 5 ; A C R I In the ASCII code, A was represented by 65. Lets' s look at the characters entered in the computer. 10 FOR IVI=32 TO 255 20 PRINT CHR$(Mj>; 30 NEXT M RUN Characters and symbols printed on KEYBOARD are displayed in rows. These are characters and symbols contained in the computer. Look at the character set. Notice that codes displayed on the code table and the screen are the same. - 82 -

LEFTS, RIGHTS, MIDS These are functions which take out part of the characters from the lengthy character strings. 10 AS = " COFFEE COCOA MILK " 2 0 MS = LEFTS (AS, 6) 3 0 PRINT MS — (String up to the 6th character from the left) RUN COFFEE Take out the character string up to the 6th character in A S (space is also counted ) and substitute it in M S so that these are displayed on the screen. 10 AS = " COFFEE COCOA MILK " 2 0 MS = RIGHTS (AS, 4) 3 0 PRINT MS f RUN String up to the 4th character from the right. - 83 -

Now, take out characters from the 4th character from the right up to the end. 10 A$ = " COFFEE COCOA MILK 2 0 M$ = MID$ (A$, 8, 5) 3 0 PRINT M$ \ \ \ \ RUN COCOA No. of characters to be taken out. Starting point Take out 5 characters starting from the 8th character from the left of the character string. LEN (length) LEN ( A $ ) will give you the counted character numbers of A $ . Also in this case, characters include all, even the space enclosed by " " . In " " , even if characters consist of space only, these spaces are treated as characters. 10 A$="SEGA PERSONAL COMPUTER" 20 PRINT LEN(A$) RUN 2 2 - 84 -

LEN gives you the character numbers including spaces. The following way of use is also possible. 10 = 20 FOR 1=1 TO,LEN(A$) 30 PRINT LEFT$CA$,I) 40 NEXT I RUN * * * * * * * * * * I ^1. »T'» *T'> STR$, VAL These convert values into string variables or convert numeric string used as string variables into values. - 85 -

STR$ 10 A = 1 : B = 3 20 D $ = S T R $ ( A ) +S T R $ ( B ) 3 0 D = A + B 40 PRINT D$,D RUN 1 , .? 4 <— Result of line No. 30 ' Result of line No. 20 When STR$(A) is entered, numerics convert into characters. In the addition of characters, characters are in a row but no calculation answer is displayed. VAL VAL functions have features quite opposite to STR $ and convert character string numerics into values. - 86 -

10 A $ = " 1 2 3 4 5 " 2 0 B $ = " 1 1 1 1 1 " 30 C$=A$ + B$ ^ Addition of character string 40 C=VALCA$)+VAL(B$) Addition of values 50 PRINT C$ 60 PRINT C RUN 1234511111 Character string 2 3 4 5 6 <— Numeral value TIMES The computer has built-in clock functions provided inside. The clock is an accurate digital quartz clock with a quartz oscillation mechanism. When the computer power switch is turned on, the clock starts to work in increments of 1 second from that moment on. When the power is turned on, the display is as follows : 00:00:00 - 87 -

After a specific time elapse, the time elapsed is displayed. , PRINT TIMES I C R I 0 0:12^32 ^ Time after power switch was turned on. When it is used as a clock, the following applies. 10 TIMES =" 08 : 15 : 00 " Current time ( " hour : 20 CURSOR 15,15:PRINT TIMES 30 GOTO 20 Once the time is entered, it will remain set until the I RESET ] key is pressed power is turned off. SPC (space), TAB (tabulation) These are used in PRINT statement. SPC functions assign spaces between characters. minute : second '' ) or the - 88 -

10 PRINT "ABC" ;SPC(10) ; "XYZ" RUN ABC I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I XYZ 10 spaces If characters are within the range assigned by SPC, these will be deleted. TAB FN (function) assignment defines that at which character No., counting from the screen end, the tabulation position is to be displayed, 10 PRINT TAB(5);"ABC" RUN I 1 1 1 1 1 1 1 1 I ABC Spaces corresponding to 5 characters. In the case of TAB FN, even if characters exist between the assigned tabulation positions, these characters are not deleted. This function is used in PRINT statements. So be sure to keep this in mind. - 89 -

INKEY$ This statement is to check which one of the keys for characters or numerics was pressed. Like in games, it is useful to move some kind of patterns by the KEYBOARD. 1 0 X $ = 1 N K E Y $ 2 0 1 F X $ = " " THEN 1 0 3 0 P R 1 N T X $ ; 4 0 GOTO 10 Line No. 20 checks to see whether a key has been pressed. Where nothing is entered, X$ value is referred to as null string. In this case, nothing is displayed and execution is endlessly repeated between line No. 10 and 20 (referred to as infinite loop). When any key is pressed, the key value is substituted in X$ and displayed by line No. 30. In order to get out of this infinite loop, add the following. 25 IF X$="Z" THEN 100 100 PRINT " END ":END Then, when the Z key is pressed, program ends. Example Operation can be started by . - 90 -

10 DIM D (29) 20 CLS 30 X=18: Y=20 40 D (29) = -1 : D (28) = 1 ; D (0) = 0 50 K$= INKEY$ 60 IF K$ = '' " THEN K = 0 : GOTO 90 70 K = ASC (K $ ) 80 IF K >29 THEN K = 0 90 X = X + D (K) 100 IF X<0 THEN X = 0 110 IF X >33 THEN X = 33 120 CURSOR X , Y ; PRINT " I + I " 130 GOTO 50 FRE As programs are entered, the remaining memory decreases. FRE FN (function) is used to determine how much space is left in the computer's memory. -91 -

Example PRINT F R E ' 8 3 0 0 This means that additional programs of up to 8300 BYTES can still be entered. PRINTER CONTROL COMMAND LLIST Print the program list on PRINTER. The command statement is used in the same manner as in the LIST. LLIST LLIST LLIST LLIST LLIST Prints the whole program. Line No. Prints assigned line numbers. Line No. — Line No. Line No. Line No. — - 92 -

LPRINT This causes the computer to print the content of the PRINT statement on the PRINTER. O How to apply the command statement is the same as in the PRINT statement. LPRINT A prints the content of A on the PRINTER. 10 INPUT A , B 2 0 C =A + B 30 LPRINT C 40 GOTO 10 RUN C value is printed on the PRINTER. HCOPY Characters and symbols displayed on the TV screen are printed on the PRINTER by this command. The PRINTER can print numerics, capital and small letters, and ASCII Code symbols. Graphic mode symbols and Dieresis characters cannot be printed. - 93 -

Chapter 5. Graphics Let's use graphics The SC-3CX)0 has two screens available to the user, the text screen and the graphics screen. The text screen cannot display graphics other than graphic characters, and cannot show more than two colors at a time. The graphic screen can have all fifteen colors displayed at the same time, and can use commands such as LINE, CIRCLE and PAINT to draw shapes on the screen. The graphic screen is made up of a grid of dots. We have to be able to describe the position on the screen that we wish to plot. We do this by first giving a number between 0—255, this is how far across the screen. We then give a number between 0-191, which is how far down the screen. eg. PSET will set a single dot in the color that you choose. ' To set a dot in the middle of the screen we go half way across (127 is halfway across the screen) and halfway down (95 is halfway down the screen). - 94 -

We would have to put: PSET(127,95),8 L This is the color red. To make the computer do this we will enter a short program. This selects the graphic screen. 1 0 SCREEN 2 , 2 : C L S This sets the dot . 2 0 P S E T ( 1 2 7 ^, 9 5 ) , 8 This is to stop the program 3 0 GOTO 30 from finishing and returning to the text screen. SCREEN SCREEN statement selects the writing screen and display screen. If the screen is used only for the text, SCREEN assignment is unnecessary. The SCREEN statement is used when displaying characters and graphics on the screen. - 95 -

Selects the graphic screen. Stops the program from finishing and going back to the text screen. 10 SCREEN 2,2;CLS 20 GOTO 20 Push the I BREAK"! key to stop the program. SCREEN Writing screen , Display screen * Text screen Graphic screen * Assignment of writing screen Assignment of display screen PRINT or drawing for CLS, etc. - 96 -

COLOR The color command allows you to select colors for the different parts of the display. Text screen (screen on which program is entered) (Screen 1) The writing color assigns colors for characters, etc. In the example, characters are in black and the background is in blue. (Example) COLOR , Color for writing / Color for background Graphic screen (displayed by graphic statement) (Screen 2) The writing color refers to the following: Character color by PRINT statement. Color for lines or dots by LINE and PSET statements. LINE, Painting color by PAINT statement. -97 -

THE BACKGROUND COLOR A range must be given for the background color . The corners of a box containing the area to Ijave the background color are given. gg , Writing color black I I Backdrop color blue COLOR 1,8 , ( 0 , 0 ) - ( 255 , 191 ) , 4 I I Bottom right of screen ' Top left of screen Background color red This will put the color red on the whole screen, with blue as the backdrop (the very top and bottom of the screen) color. COLOR 1,8 . ( 0 , 0 ) - ( 127 , 191 ) , 4 This will put the color red on the left half of the screen, leaving the right half unchanged. - 98 -

0 255 COLOR 1 , 8 , ( 10 . 10 ) - ( 50 , 50 ) , 4 This will put the color red in the box with the corners (10 , 10) and (50 , 50). 0 255 - 99 -

Example 10 C L S 20 FOR C=0 TO 15 30 COLOR 1,C Colors on the screen consecutively change. Color No. Color 0 Transparent 1 Black 2 Green 3 Light green 4 Dark blue 5 Light blue 6 Dark red 7 Cyan 8 Red 4 0 5 0 FOR 1=0 TO 300 NEXT I , C Color No. Color 9 Light red 10 Deep yellow 11 Light yellow 12 Dark green 13 Magenta 14 Gray 15 White 100 -

LINE Line statenaent causes the computer to draw 0 255 lines after SCREEN 2,2 are entered. The graphic screen has a coordinate with 0 - 225 (256 dots) in the x direction and one with 0 - 191 (192 dots) in the y direction. The LINE statement causes the computer to draw lines by assigning coordinates between 2 points. Screen examples ( 1 ) L I N E ( 50 ( 2 ) L I N E ( 50 50 ) - ( 200 , 50 ) , 1 1 00 ) - ( 200 , 1 50 ; , 8 Black color assignment Red color assignment - 101 -

BLINE BLINE statement functions erase lines and the box drawn by LINE statements. It is used in 'the same way as the LINE statement except that color assignment is unnecessary. 10 SCREEN2,2:CLS 20 LINE(50,50)-(200,50),1 30 FOR 1=0 TO 300:NEXT I Takes time 40 BLINE(50,50)-(200,50) 50 GOTO 50 For erasing the box the same applies. However, when drawing a box smaller than the drawn box by BLINE, the color of the particular portion disappears. The BLINE statement is used to erase all the graphics previously drawn or part thereof. PAINT Paint screen portions separated by LINE statement or CIRCLE statement. - 102 -

-103 PAINT (x,y) , color Paint portions enclosed by coordinate lines where painting starts from. Paint the entire periphery. — Box drawn by line and BF statements.

1 0 SCREEN 2 , 2 : C L S Draws a blue line 2 0 L 1 N E ( 1 0 0 . 1 0 ) - ( 1 0 , 1 8 0 ) , 5 Draws a red line 3 0 L 1 N E ( 9 0 . 5 ) - ( 9 0 , 1 9 0 ) , 8 Draws a green line 4 0 LINE(5,80)-(150 , 8 0 ) , 2 PAINT area in middle 5 0 P A 1 N T ( 8 0 , 5 0 ) , 1 with color black 6 0 GOTO 60 CIRCLE Now, let’s draw circles. Line drawings or the CIRCLE inside can be painted. Various values enter the CIRCLE statement. So, when entering values, refer to the text until you become familiar with the statement. (1) , (2) , (3) . (4) , (5) , (6) (7) Coordinate, Radius, Color, Ratio, Start Point, End Point CIRCLE ( 1 25,95 ) , 50 , 5 1,0, 1 , be -104

Explanation of examples (1) Coordinate x=125, y=95 (255 (max.) in the x direction. (2) Radius (3) Color (4) Ratio 191 (max.) in the y direction.) Radius from the center 0~15 at 1 True roundness (5) Start point Less than 1 Ellipse (long sideways) Greater than 1 Ellipse (longitudinally long) Position where printing starts from. (Enter numerics between 0~1 with decimal fractions.) (6) End point position where printing ends. (7) When BE is not assigned, only a circumference is drawn. When B is assigned, lines can be drawn inside also. When BF is assigned, the assigned color is used for painting part or the whole of the circle. - 105 -

0.75 -106 0.75 Ratio 2

Draws a blue circle 10 SCREEN 2,2:CLS 20 CIRCLE(130,100),30,4 30 GOTO 30 Draws a red 10 SCREEN 2,2:CLS eclipse 20 CIRCLEC127,95),30,8,.5 30 GOTO 30 Draws an open 10 SCREEN 2,2:CLS circle 20 CIRCLE(127,95),30,8.1 ,0, .75 30 GOTO 30 Draws a closed 10 SCREEN 2,2:CLS partial circle 20 CIRCLE(127,95),30,8,1,0,.75,B 30 GOTO 30 Draws a filled 10 SCREEN 2,2:CLS partial circle 20 CIRCLE(127,95),30,8,1 ,0, .75, BE 30 GOTO 30 Draws a filled 10 SCREEN 2,2:CLS complete circle 20 CIRCLE(127.95),30,8,,,,BF 30 GOTO 30 - 107 -

BCIRCLE BCIRCLE is used when erasing circles drawn by CIRCLE statements . In this case, color assignment is disregarded and CIRCLE is drawn in the same color as the background, so CIRCLE becomes unnoticeable. following program to the previous program. 1 0 SCREEN 2,2:CLS 2 0 FOR R=10 TO 50 STEP 1 0 3 0 CIRCLE(125,95),R,8 Draws & 4 0 NEXT R erases 5 0 FOR R=10 TO 50 STEP 1 0 circles. 6 0 BCIRCLE(125,95),R.1 » 7 0 NEXT R 8 0 GOTO 10 1 0 SCREEN 2,2:CLS Draws a 2 0 LINE(20,20)-(240,17 0 ) , circle 3 0 BCIRCLE(128.96).30, f t > inside 4 0 GOTO 40 a box 6 , B F , B F - 108 -

PSET This statement allows setting of dots in the specified position on the screen. ^ ! PSET(x,y),1 Coordinates color By consecutively varying coordinates, straight lines and curves can be drawn. 1 0 SCREEN 2 , 2 : C L S 2 0 II > o II X 9 5 : E = 1 3 0 P S E T (X , Y ) , 8 4 0 X = X+ 1 : Y = Y + E 5 0 IF Y = 1 2 0 THEN E =- 1 5 5 1 F Y = 8 5 THEN E = 1 6 0 IF X = 2 5 0 THEN END 7 0 GOTO 3 0 PSET allows setting of dots and the generation of graphs by using mathematical functions. - 109 -

PRESET PRESET erases dots, counterworking to PSET. Application is the same as in PSET except that PRESET plays the role to erase dots instead of generating them. Coordinates PRESET(x,y) POSITION The upper left position of the coordinates is 0. assigned by POSITION statements, the assigned which is x=0, y=0. X y axis axis POSITIONflOO, 80)0,0 1 I ^ Axial direction of x — j Axial direction of y When coordinates are position becomes the center X =0 X =100 (x =0, y =0) J - 110 -

Numeric values following coordinate symbols define the increase directions of x axis and y axis. Increase with With 0 Assignment, X values increase to the right and y values increase downward. With 1 assignment, x values increase to the left, and y values increase upward. 1 assignment (y) Increase with 1 assignment (x) r" 1 (X = 0 , y = 0 ) Where x and y assignments are combined, the value increases in the directions of x axis and y axis can be varied. Increase with 0 assignment (y) Increase with 0 assignment (x) Normally the screen is set at POSITION (0,0), 0,0. When the reset button is pressed it will return to this. -Ill-

1 0 SCREEN 2 . 2 : C L S 2 0 P 0 S 1 T 1 0 N ( 1 2 5 , 9 5 ) , 1 3 0 FOR N = 0 TO 5 0 4 0 P S E T f X . Y ) . 1 5 0 X = X + 1 : Y = Y + 1 6 0 NEXT N 1 , 1 125 y = 95 The combined use of POSITION statements and PSET permits Fn (function) graph drawing. -100 155 10 SCREEN 2,2:CLS 20 POSITION(100,50),0,0 30 FOR N=-10 TO 1 STEP.1 40 X = N * 2 0 + 1 2 0 : Y = S I N ( N ) * 5 0 + 4 5 50 PSET (X,Y),1 60 NEXT N 141 r (0, 0) L - 112 -

PATTERN Using PATTERN statements, characters and graphic characters can be generated. Let's rewrite the text mode characters. PATTERN C# Character code (32—255 or &H20—&HFF), "Character-String expression" "Character-string expression (hexadecimal) LEFT RIGHT LEFT RIGHT 0 1 1 1 0 0 0 0 7 0 1 0 0 0 1 0 0 0 8 8 1 0 0 1 1 0 0 0 9 8 1 0 1 0 1 0 0 0 A 8 1 1 0 0 1 0 0 0 C 8 1 0 0 0 1 0 0 0 8 8 0 1 1 1 0 0 0 0 7 0 0 0 0 0 0 0 0 0 0 0 Black location = 1 , White location = 0 - 113 -

Let's assign the above graphic characters to the space key. 20 PATTERNC #&H20, " 708898A8C8887000 " RUN Now, press the space key. You notice that “0” is displayed. This is because “0” was printed in the space. Push the I RESETlI button to return the character to its normal pattern. As above, characters can be easily generated. Pattern characters to be displayed on the graphic screen are also printed in the same manner. Make sure that application procedures are properly understood. C# Text mode assignment Character code: In the case of hexadecimal numerals, input numerics from &H 20 to &HFF. In the case of decimal numerals, input numerics from 32 to 255. Character string expression: Characters and patterns can be drawn by painting 8x8 dots in black. - 114 -

Assign 1 and 0 for respective columns, with black dots assigned as 1 and white dots as 0. becomes 01110000. This is separted from the center into two portions and then converted into hexadecimal numerals. S# : Assignment of graphic screen Sprite name; Numbers from 0 to 255 are assigned. Character string: Entering to be same as the text mode. 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 1 1 0 3 0 0 0 0 0 1 1 1 0 7 0 0 0 0 1 1 1 1 0 F 0 0 0 1 1 1 1 1 1 F 0 0 1 1 1 1 1 1 3 F 0 1 1 1 1 1 1 1 7 F 1 1 1 1 1 1 1 1 F F - 115 -

10 SCREEN 2,2:CLS 20 PATTERNS# 0," 0103070F1F3F7FFF'' 30 SPRITE 0, (10,0), 0,1 RUN A ^ This mark is displayed or SCREEN 2. 0111 is 7 and 0000 is 0 and this results in “70”. Try to generate characters as per the above. HOW TO DRAW PATTERNS To begin with, divide graph sheets into 8x8 locations and paint a dot (location) to generate a pattern. The painted location is assigned as 1 and the blank one, as 0. Arrange 0 and 1 numerals beside locations. Divide the eight numerals in a row into two equal parts from the center, each part being four digits. The four digit numerals represent binary numerals. - 116 -

These are converted into hexadecimal numerals of two digits. Refer to the comparison table of decimal binary and hexadecimal numerals. The eight sets of numerics converted into hexadecimal numerals are substituted in " " as character string variables. In this way characters are expressed by 8x6. Decimal Numerals Binary Numerals Hexadecimal Numerals Decimal Numerals Binary Numerals Hexadecimal Numerals 0 0000 0 9 1001 9 1 0001 1 10 (Carry) 1010 A 2 0010 (Carry) 2 11 1011 B 3 0011 3 12 1100 C 4 0100 4 13 1101 D 5 0101 5 14 1110 E 6 0110 6 15 1111 F 7 0111 7 16 10000 10 (Carry) 8 1000 * - 117 -

MAG The MAG statement assigns the magnitude of graphic characters to he drawn on sprite planes hy PATTERN statement. MAG 0 MAG 1 8 hit — 1 hit = 1 dot 16 hit ^ #0 #2 #1 # 3 Four of MAG 0 are combined to draw the pattern. - 118 -

MAG 2 MAG 3 h~ 8 dots 16 dots 32 bit — 16 dots 8—1 32 bit #2 #1 #3 - 119 - 2 bit X 2 bit is deemed as 1 dot. Patterns are drawn by combining four MAG 2.

In MAG 0, patterns are drawn within 8x8 dot locations with 1 bit as 1 dot. In MAG 1, patterns can be drawn within 16x16 dot locations by combining four locations, i.e:, #0~3, #4~#7 #252~#255. In MAG 2, patterns are drawn within 8x8 dot locations with 2 bit x 2 bit as one dot. The bit number is 16 bit x 16 bit. In MAG 3, patterns can be drawn by combining four locations as assigned in MAG 2. In this case, the bit number will be 32 bit x 32 bit. SPRITE MAG statement, PATTERN statement and SPRITE statement are absolutely necessary when using sprite functions. 0~31 Coordinate SPRITE Graphic screen No., (x,y). Sprite name. Color There are 32 graphic screens (0~31) and the SPRITE statement assigns the number of tbe graphic screen on which the sprite is to be drawn. - 120 -

Graphic screen No. 0 takes the foremost position and as the number increases, the graphic screen's position becomes progressively more and more in the background. When graphic screens are intersected, the one with a smaller number takes precedence. Coordinates used are 0~255 (x) and 0~191 (y). The upper left coordinates define the position assigned by the PATTERN statement. SPRITE name refers to the S# name defined by the PATTERN statement. If there are clearances in a pattern drawn by the PATTERN statement, the screen behind the preceding one will be seen through the clearance. Taking advantage of this situation, deep and solid patterns can be generated. -12 1 -

Note: At the maximum, 4 patterns of the graphic screen can be displayed on the horizontal line. Where more than 4 patterns are in a row horizontally, the 4 patterns which have the highest priority will be displayed. - 122 -

Chapter 6. Mathematical Function - 2 The computer excels in calculations. Various functions including trigonometric function are built into the computer in order to increase the calculation function. ABS (X) Function: Gives absolute value of expression X Form: A B S ( X ) How to use: print ABS(-5) | C R | 5 PRINT ABS(3*(-6i) | C R | 1 8 RAD Function: Form: Angular degrees are converted into radians. RAD (X) How to use: 0°, 15°, 30°, 45° and 60° are converted into radians. 10 F0RI=0 TO 60 STEP 15 2 0 X = R A D ( 1 ) 3 0 P R I N T " R A D ( " : I ; " ° : 123 -

40 NEXT I RUN DEG Function: Form: How to use: PI Function; Form ; How to use: R AD ( 0“ J =0 RADC 1 5°) = . 261 7993878 RAD(30°)=. 5235987756 Radians are converted into degrees. DEG (X) X refers to radian. PRINT DEG (0.26) | C R | 14.896902673 The ratio of the circumference of a circle to PRINT PI I C R (3.1415926536) its diameter is defined. - 124 -

SIN (Sine) Function; Form: How to use; 10 INPUT " RADIUS ";A 20 S=A^2>I<PI 30 PRINT "AREA OF CIRCLE" ;S RUN RADIUS 5 AREA OF CIRCLE 78.539816333 Defines the values of trigonometric function and sine. SIN (X) Argument (X) refers to radian. 1 0 FOR TH=0 TO 90 STEP 2 0 S = S 1 N ( R A D ( T H ) ) 3 0 PRINT th:tab(io) ;s 4 0 NEXT T H RUN 0 0 3 0 . 5 6 0 . 86602540379 9 0 1 - 125 -

cos (Cosine) Function: Defines the values of trigonometric function and cosine. For-m: COS (X) Argument (X) radian How to use: 10 FOR X=0 TO 90 STEP 30 20 A=COS(RADCX)) 30 PRINT x;tab(io);a 40 NEXT X RUN 0 1 30 .86602540379 60 .50000000001 9 0 0 TAN (Tangent) Function: Defines the values of trigonometric function and sine. Form: TAN (X) Argument (X) refers to radian. How to use: - 126 -

10 INPUT "degree" ;a 20 X=TAN(RAD(A)) 3 0 P R I N T " T A N ( " ; A : " ° : X RUN DEGREE 30 TAN(30°)= .57735026919 ASN (Arc Sine) Function: Obtains the 0 value (degree) of SIN 0 Form: ASN (X) (where X is —1~1) How to use: 10 X = A S N ( . 5 ) 20 Y=DEG(X) 30 PRINT Y RUN 3 0 - 127 -

ACS (Arc cosine) Function; Obtains the 0 value (degree) of COS 0 Form: ACS (X) (Where X is -1~1) How to use; 10 X =A C S ( - 1 ) 20 Y=DEG(XJ 30 PRINT Y RUN 1 8 0 ATN (Arc Tangent) Function; Obtains the value of the arc tangent. Form; ATN (X) TT 71 How to use; Values to be obtained range between — to ^ 10 X = A T N ( 1 ) 20 PRINT X RUN . 7853981 634 - 128 -

LTW Function: Form: How to use: LGT Function: Form: How to use: Obtains common logarithm with 2 as a base. LTW (X) Same as in LOG. Obtains the common logarithm of the value with 10 as a base. LGT (X) Obtains the common logarithm of 10, 100 and 1,000. 1 0 N = 1 2 0 N = N * 1 0 3 0 X = L G T ( N 4 0 P R 1 N T II L G T ( " ; N : " } = 5 0 I F N < 1 0 0 0 THEN 20 R U N L G T ( 1 0 ) = 1 L G T ( 1 0 0 ) = 2 L G T ( 1 0 0 0 ) = 3 - 129 -

EXP Function: Form: How to use: SGN (Sign) Function: Form: How to use: Obtains raising to power of the natural logarithm with e as a base. EXP(X) .1 .e^ . and e^ are obtained respectively. 1 0 F 0 R I = 1 T 0 3 2 0 X = E X p ( I ) 3 0 P R 1 N T II E X p ( " : 1 ; " ) " 4 0 N E X T I RUN EXP(1 )=2. 7182818284 EXP(2) = 7. 3890560987 EXP(3)=20. 085536923 SGN Fn assigns value signs. When X value is negative — 1 0 0 positive 1 SGN (X) - 130 -

LOG Function; Form: How to use: 10 FOR I=-2 TO 2 2 0 N = S G N i I ) 3 0 P R I N T " S G N { " ; I ; " ) = " : N 40 NEXT I RUN S G N ( - 2 ) =- 1 S G N ( - 1 ) =- 1 S G N ( 0 ) = 0 S G N ( 1 ) = 1 S G N ( 2 ) = 1 Obtains the natural logarithm of value with e as a base. LOG (X) 1 0 FOR J = 1 T 0 3 2 0 X = L 0 G ( J ) - Argument J is a positive value. 3 0 PRINT" L 0 G ( " : J ; " 1 = " : X 4 0 NEXT J -13 1 -

RUN LOG( 1 ) = 2 . 67468532E-1 1 L0G(2)= .69314718057 LOG(3 ) = ^ .09861 22886 SQR Function: Obtains the square root of the value. Form: SQR (X) How to use: and are obtained as follows. 10 INPUT " NUMERAL ";A 20 X=SQR(A) 3 0 P R 1 N T " R 0 0 T " ; A ; " = " ; 40 GOTO 10 RUN NUMERAL 2 ROOT=1 .4142135624 NUMERAL 3 R00T = 1 .7320508076 - 132 -

HEX$ Function: Form: How to use: Decimal numerals are converted into hexadecimal numerals. HEX$ (X) Values convertible into hexadecimal numerals range from —32768~32767. Values —10, —5, 0, 5, 10 and 15 are converted into hexadecimal numerals. 10 FOR S=-10 TO 15 STEP 5 20 X$=HEX$(S) 30 PRINT s;"=":x$ 40 NEXT S RUN - 1 0 = F F F 6 - 5 = F F F B 0 = 0 5 = 5 1 0=A 1 5 = F - 133 -

INP Reads out the content of I/O Areas. This function is the opposite of OUT. Assigns I/O port No. and reads out the data which is on the port. How to apply: 10 A=INP(&HBE) 20 PRINT A RUN 3 2 In line No. 10, the data of the I/O port No. BE (hexadecimal numerals) is read out to variable A. In this case, the results may vary depending on the situation of the computer. The I/O port numbers which were defined in the system in advance are integers 0~255 (&HOO~&HFF). Situations of outside input devices including Joysticks can be recognised by the above command. DEF FN This is a function which computer operting personnel define arbitrarily. - 134 -

The ratio of the circumference of a circle to its diameter. 5 REM AREA OF CIRCLE 10 DEF FNS(R)=R*R*3. 14159 20 INPUT "radius=";a 30 Z=FNS(A) 40 PRINT 50 PRINT "AREA=";Z 6 0 END RUN RAD I U S = 1 0 AREA=314.15 DEF FNS (R) =R* R* 3. 14159 For the above formula, the right side expression can be defined as the function of the left side expression FNS (R). When entering the radius, the Fn (function) which was defined by line No. 30 is called for calculation. (R) is only a dummy argument, the number returned will be a function of whatever number or variable that is in the brackets when the function is called. - 135 -

Frequency Table SCALES f 1 f 2 f3 f4 f 5 f 6 C 1 31 262 523 1 047 2094 C* - D& 1 39 277 554 1 1 09 221 8 D 1 47 294 587 1 1 75 2350 D+ , eI> 1 56 31 1 622 1 245 2490 E 165 330 659 131 9 2638 F 1 75 349 698 1 397 2794 F+ , 1 85 370 740 1 480 2960 G 1 96 392 784 1 568 3136 G* , Ab 208 41 5 831 1 661 3322 A 1 1 0 220 440 880 1 760 3520 A* , Bb 1 1 7 233 466 932 1 864 B 1 23 247 494 988 1 976 Frequency unit Hz. - 136 -

BEEP This is used for producing a short sound in programs. BEEP Makes beep sound. BEEP 0 Stops beep sound. BEEP 1 Continues beep sound. BEEP 2 Makes beep beep sound. Example ; 1 0 A$="SEGA PERSONA L COMPUTER" 2 0 FOR 1=1 TO LENI: A $ ) 3 0 PRINT IVIID$(A$, 1 , 1 ) : 4 0 BEEP 5 0 FOR J=0 TO 100:: N EXT J , 1 6 0 END - 137 -

SOUND SC — 3000 has a synthesizing function. Example SOUND 1,1000,15 t Sound volume Frequency Channel Sound of 1000 Hz is produced. ( Channel ) Only one sound is produced from one channel. Six channel assignments (0— 5) are possible. (Sound up to treble chord can be produced.) 0 : Silences noise. Example SOUND 0 1 ~3 : Sound from 110 Hz is produced. 4 : Selection of white noise. 5 ; Selection of synchronous noise. - 138 -

( Frequency When channels 1~3 are assigned, frequency (Hz.) is entered. When channel 4 or 5 is assigned : 0~2 : Frequencies of 3 defined steps are assigned. 3 : Frequency is assigned by channel 3. ( Sound Volume 0 : Silences noise. 1 • Minimum sound volume. I 1 5 : Maximun sound volume. By the above, effect (sound) for games, etc. can be produced, and melodies can be heard in accordance with the following table. OUT Data is output to the output port by this statement. The output port No. is defined in the system in advance to output data to the outside. - 139 -

Output port numbers are integers from 0 to 255 (& HOO & HFF). VDP data register Command register Sound generator &H BE &H BF &H 7F POKE, PEEK, CALL Programs when entered by BASIC are memorized in the MEMORY in their respective order. In addtion, data and the machine language can be printed in the specific memory. POKE POKE command Address Data POKE &H 9000, 65 The address covers from &H 8000 (-32768) to &HFFFF. DATA are integers from 0 to 255. Note that the address varies depending on the used quantity of MEMORY, BASIC version and types. - 140 -

PEEK Function Address Read out command A = PEEK ( &H9000) fteads out the content of assigned address memory. Main memory map ROM ( exclusively for read out ) POKE command is unusable. RAM (Area) ( At the actual capacity of 32k Byte) DATA conversion program 10 REM *** DATA CONVERSION 20 INPUT "data=";d & H 0 0 0 0 & H 7 F F F & H 8 0 0 0 & H F F F F BASIC Area TEXT Area -14 1 -

30 IF D=>256 THEN GOTO 20 40 P0KE&H9000,D 50 A=PEEK(&H9000J 70 B$=CHR$(A) 8 0 PRINT A ; " = " : B $ 90 GOTO 20 RUN D A T A = 6 5 6 5 = A DATA =H In this program, entered values are converted into symbols. When exceeding 256, the value should be entered again. No symbol output means that there is no symbol corresponding to the value available. CALL This calls the address printed by the machine language. Differing from the BASIC language, the machine language should be mastered separately from the former ( BASIC ) - 142 -

The incorrect use of the machine language may damage the program. So take care. You could learn the machine language at some other opportune time. V POKE ADDRESS ASCII DATA (Text mode) 0 1 2 23 39 Columns Address &H3C00 ( Sideways ) ( Longitudinal 40 digits X 24 columns = 960 bytes TEXT MODE Ordinary text mode screen 38 columns sideways SCREEN 1 (0-255) 0 ~ 255 Address &H0000 191' GRAPHIC MODE 256 dots X 192 dots/8 ( Sideways ) ( Longitudinal = 6144 bytes SCREEN 2 Part of VRAM MAP - 143 -

The address calculations on the text screen are carried out as follows. Address (text) = y 40+ x + &H3C00 where (x = 0—39, y = 0~23) For the data to be sent, the ASCII code of the corresponding character is applicable (0-'255 in decimal numerals and 0- &HFF in hexadecimal numerals). Note : As shown in the left figure above, the horizontal axis is deviated by 2 columns as compared to the ordinary text screen. Thus, the display position defined by CURSOR statement deviates from that defined by VPOKE, by about 2 locations in the horizontal direction. (See page i46.) VPOKE ADDRESS, DATA (For graphic screen) Graphic address calculations are carried out as follows. Graphic address = INT(y/8)*256+INT(x/8)>h8+y MOD 8 where ( 3 ^ is 0—191 ,xis 0-255 ) The address derived from the above calculations is the beginning address of 8 bits ( dots ) in the assigned horizontal direction. The assigned address is the x-INT (x / 8 ) bit location counting from the left of the beginning address. - 144 -

The data to be sent are hexadecimal or decimal numerals displayed by the bit pattern in a horizonal row. Example I 'mi I O & H 9 3 ( 1 47 ) Similarly, the color table address for graphic color assignment is derived from the addition of &H 2000 to the above address. The data to be sent are natural numbers (0- 255) of IB (1 Byte). The upper 4 bits of these numbers converted into binary data are the assigned color number, and the lower 4 bits, the background color number. (The addresses of the graphic pattern generator table and color table respectively corresponds at 1 : 1). Graphic color table address = INT(y/8 )*256+INT(x/8 1*8 + 3; MOD 8 + &H2000 Where O' is 0 ~ 1 9 X is 0 ~ 2 5 5 Color data = Assigned color No. 16+ background color No. (0---15) (0~15) - 145 -

SCREEN DISPLAY SCREEN 1 y 24 digits in longitudinal direction - 146 -

VPEEK Use VPEEK with reference to VPOKE address. Program to read the content of the pattern generator table in VRAM. Example 1 0 2 0 3 0 4 0 5 0 2 0 6 0 2 0 2 0 2 0 2 0 7 0 0 0 1 1 1 1 1 1 1 1 1 1 AD = &H1800+&H31=)«8 :REI\/1 The beginning address FORA=ADTOAD + 7 of REM " 1 " pattern DA = VPEEK(A ) PRINT HEX$(DAJ) NEXT A - 147 -

VRAM MAP ,& HOOOO & HI 800 & H2000 & H3800 & H3B00 & H3C00 VRAM ( 16K bytes) ) Graphic 2 mode Pattern generator table ( 6144 bytes ) Note 1 Graphic 2 mode color table ( 6144 bytes ) Graphic 2 Mode pattern name table Sprite attribute table ( Empty ) Text mode pattern name table { Empty ) 1 48-

Note : STICK STRIG The contents of the table for 2K Bytes of &H1800 &H 1 FFF varies depending on the display mode ( text /graphic ). The table contents of the mode on the unselected side is SAVEed in the MEMORY (RAM). (n) (Value -to be obtained) 1 Parameter : 1 = Joystick 1 2 = Joystick 2 (n) Left 7 8 ' 2 0 6 ' 4 3 Right 5 Bottom ( Value to be obtained ^ Parameter : 1 : Joystick 1 2 : Joystick 2 0 : off 1 : Trigger (left) ON 2 : Trigger (right) ON 3 : Trigger (left, right) ON - 1 4 9 -

STICK, STRIG Program to find out the situation of connected JOYSTICK. 1 0 R E M JOY S T 1 C K T E S T 2 0 B $ = " SHOOT II C L S 3 0 P 1 = S T 1 C K ( 1 ) P 2 = S T 1 C K ( 2 ) 4 0 S 1 = S T R 1 G ( 1 ) : S 2 = S T R 1 G C 2 ) 5 0 F 1 $ _ II " : F 2 $ = II II 6 0 1 F P 1 = 1 T H E N F 1 $ _ 11 U P II 7 0 1 F P 1 = 3 T H E N F 1 $ _ II R 1 G H T II 8 0 1 F P 1 = 5 T H E N F 1 $ _ It D OWN tl 9 0 1 F P 1 = 7 T H E N F 1 $ _ II L EFT II 1 0 0 1 F P 2 = 1 T H E N F 2 $ = U P II 1 1 0 1 F P 2 = 3 T H E N F 2 $ = RIGHT IT 1 2 0 1 F P 2 = 5 T H E N F 2 $ = D OWN It 1 3 0 1 F P 2 = 7 T H E N F 2 $ = LEFT II 1 4 0 1 F S 1 >0 T H E N F 1 $ = F 1 $ + B $ + S T R N G $ 1 5 0 1 F s 2 > 0 T H E N F 2 $ = F 2$+B$+STR N G $ 1 6 0 C U R S 0 R 1 1 0 P R 1 N T P L A Y E R 1 " F 1 $ 1 7 0 C U R S 0 R 1 1 5 P R 1 N T P L A Y E R 2 " F 2 $ 1 8 0 GOTO 2 0 - 150 -

APPENDIX Variables and Arrays A, B. Z, AA, AB, ZZ A 0. A 1 A 9 (Subscript, ) Up to 3 - DIM A (15), B (5, 5), AC (3, 3, 3) A$,AB$,A1$ (Subscript, ) Up to 3 — DIM A $ ( 15), B $ (5, 5), AC $ (3, 3, 3) • For variable names, tbe first character is an alphabetic character and then after, alphabetic characters or numerics. Although any number of characters is acceptable, separation is made by the beginning 2 characters. • The names of variables and arrays may be the same. ( Range of numeric variables and arrays ±9.9999999999E-99 I ±9.9999999999E + 99 Numeric variables Numeric array String variables - String array -15 1 -

( Range of string variables and array Character length 0 — 3 1 CONSTANT Numeric constant Integer form Example 3, -2, 99926768 Decimal form Example 0.2, .3, -5.3, 86.0 Exponent form Example 3, E99, -6E3, 0.3E + 5, 4E-82 Hexadecimal form &H Hexadecimal value 0000~FFFF Example &H 64 same as 100 &HFFFF same as — 1 String constant Use double quotation to indicate " enclosed by " Example " ABC " —* Character ABC " " ^ ^ Character NULL " " " " ^ Character " "A3" " 64 " ^ Character A3" 64 - 152 -

Contents Limitation Characters taken into the inside from the screen. 256 characters Character numbers usable for actual text image by reserved words converted from line buffer. 256 characters Character numbers which can be handled as character string. 255 characters Level number such as operator priority, etc. 32 levels Area for string operation 300 characters FOR NEXT nesting level number 16 levels GOSUB, RETURN nesting level number 8 levels - 153 -

CHARACTER CODE 32 SP 48 0 64 (a) 80 P 33 ! 49 1 65 A 81 Q 34 It 50 2 66 B 82 R 35 # 51 3 67 C 83 S 36 $ 52 4 68 D 84 T 37 % 53 5 69 E 85 U 38 & 54 6 70 F 86 V 39 T 55 7 71 G 87 w 40 ( 56 8 72 H 88 X 41 ) 57 9 73 1 89 Y 42 * 58 : 74 J 90 Z 43 + 59 f 75 K 91 [ 44 f 60 < 76 L 92 ¥ 45 - 61 = 77 M 93 ] 46 62 > 78 N 94 /\ 47 / 63 7 79 0 95 TT 96 \ 112 P 97 a 113 q 98 b 114 r 99 c 115 s 100 d 116 t 101 e 117 u 102 f 118 V 103 g 119 w 104 h 120 X 105 i 121 y 106 j 122 Z 107 k 123 { 108 1 124 • • 109 m 125 } 110 n 126 111 0 127 m 144 B 145 B 146 ffl B 147 0 ffl 148 B m 149 a B 150 B 151 B 152 B 153 154 U 155 H 156 H 157 n ffl 158 n B 159 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 154 -

160 AA 176 1 192 U 161 VA 177 i 193 ij 162 A 178 1 194 0 163 A 179 Y 195 a 164 A 180 1 196 165 0A 181 T 197 e 166 A 182 A 0 198 167 A 183 6 199 168 A E 184 9 200 2 169 V E 185 6 201 0 170 E 186 6 202 O 171 E 187 0 203 9 172 E 188 6 204 6 173 E 189 u 205 1 174 N 190 V U 206 / 175 N 191 U 207 £ 224 c 240 225 n 241 226 [i 242 227 243 228 244 229 245 4 230 m 246 V 231 B 247 232 i] 248 233 g 249 © 234 250 235 251 236 252 H 237 253 238 254 o _ 239 255 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 - 155 -

CHARACTER SET 0 1 2 3 4 5 6 7 8 9 A B c D E F 0 0 @ P \ P 1 m AA 1 u 1 1 ! 1 A Q a q — X VA i u 1 2 11 2 B R b r + A 1 u 1 3 # 3 C S c s -T- / A Y a 1 4 $ 4 D T d t H \ A A 1 1 5 % 5 E U e u h OA T e 4 6 & 6 F V f V r A 6 1 4 7 t 7 G W g w L A 6 — 8 ( 8 H X h X n r E 9 2 i 9 ) 9 I Y i y _l V E 6 0 m © A * J Z j Z r MM E 6 n B + K [ k { L E 0 9 o X C < L ¥ 1 E 0 6 • H D - = M ] m } J E A u i ! E > N /\ n T N u / F / ? 0 TT 0 1 AN u £ Control code - 156 -

Command, Statement and Built in function Command No. Command Functions 1 LIST Displays programs on screen. 2 LLIST Prints programs on PRINTER. 3 SAVE Records programs on cassette tapes 4 VERIFY Compares programs in MEMORY and those recorded on cassette tapes. 5 LOAD Loads cassette tape programs on MEMORY. 6 RUN Runs programs. 7 CONT Continues discontinued programs. 8 NEW Clears variables and programs. 9 DELETE Clears programs partially. 10 AUTO Generates line numbers automatically. 11 RENUM Renumbers line numbers. - 157 -

STATEMENT NO. Statement Functions 1 , REM Comment 2 STOP Stops programs. Continuable by CONT. 3 END Completes program run. 4 LET Input substitution. LET omittable. 5 PRINT or ? Displays on display. 6 LPRINT or L? Prints on Printer. 7 INPUT Input from key. 8 READ Reads data from “DATA” statements. 9 DATA Shows data to be read from “READ” statements. 10 RESTORE Assigns positions of “DATA” statement to be read from “READ” statements. 11 DIM Declares arrays. 12 ERASE Clears declared array. 13 DEE FN Defines user function. 14 GOTO Branches to assigned address. 15 GOSUB Go to subroutine. 16 RETURN Returns from subroutine. 17 ON-GOTO Selects line numbers to be branched. ON-GOSUB Selects line numbers to be branched. 18 FOP -TO- Repeats statements between FOR and NEXT for a set number of STEP- times. STEP omissible. 19 NEXT Assigns positions of repeating by “FOR” statement.

NO. Statement Functions 20 IF-THEN Conditional branch. 21 CONSOLE Assigns the ranges of screen scroll, click sound and character set. 22 CLS Clears screen. 23 SCREEN Shifts the screen. 24 COLOR Color assignment. 25 PATTERN Changes character sprite PATTERN. 26 CURSOR Assigns display positions. 27 POSITION Assigns coordinates-. 28 PSET Displays dots. 29 PRESET Erases by dots. 30 LINE Draws lines. 31 BLINE Erases by lines. 32 CIRCLE Draws circles. 33 BCIRCLE Erases by circles. 34 PAINT Paints enclosed extent. 35 SPRITE Assigns sprite position, color and pattern. 36 MAG Assigns sprite magnitude. 37 SOUND Produces effective sound. 38 BEEP Produces beep sound. 39 HCOPY Prints text on screen on to printer. 40 CALL Branches to machine language subroutine. 41 POKE Writes in memory. 42 OUT Outputs to output port. 43 VPOKE 1 Writes data in video RAM. - 159 -

FUNCTION NO. Function Functions 1 ' ABS(X) Finds the absolute value of X. 2 RND(x) Generates random numbers 3 SIN(x) Finds the sine of X. 4 COS(x) Finds the cosine of x. 5 TAN(x) Finds the tangent of X. 6 ASN(x) Finds the arc sine of X. 7 ACS(x) Finds the arc cosine of x. 8 ATN(x) Finds the arc tangent of X. 9 LOG(x) Finds the natural logarithm of X. 10 LGT(x) Finds the common logarithm of X. 11 LTW(x) Finds the logarithm of x. with 2 as a base. 12 EXP(x) Finds e 13 RAD(x) Converts degrees into radians. 14 DEG(x) Converts radians into degrees. 15 PI Specifies the ratio of the circumference of a circle to its diameter. 16 SQR(x) Finds the square root of x. 17 INT(x) Finds the greatest integer not exceeding x. 18 SGN(x) Specifies the positive and negative codes of x. 19 ASC(s) Specifies the first code of character-string s by numeric values. 20 LEN(s) Specifies the number of character-string s. 21 VAL(s) Converts character-string s into numeric values. 22 CRH${x) Specifies the corresponding character and functions of x. - 160 -

NO. Function Functions 23 HEX$(x) Specifies the hexadecimal number character-string. 24 INKEY$(x) Checks whether or not key was pressed. When key is pressed, the character is given. (Null) if it is not pressed. 25 LEFTS (s,x) Substitutes the character-string covering from the left of the character-string s to x places. 26 RIGHTS (s,x) Substitutes the character-string covering from the right of the character-string s to x places. 27 MIDS(s.x.y ) Substitutes tbe character-string of length y from the x places of the left of the character-string. y is omissible and in this case, substitutes from x place character to the end character. 28 STRS(x) Converts x into the character-string which indicates x. 29 TIMES Determines the time of the inside clock. 30 PEEK(x) Specifies the content of the x address of memory. 31 INP(x) Specifies the input content of input port. 32 FRE Specifies memory area space for users. 33 SPC(x) Used by print statement. Provides space. 34 TAB(x) Used by print statement. Assigns display positions. 35 STICK(n) Shows the n direction of joysticks. 36 STRIG(n) Shows the trigger button condition of joystick n. 37 VPEEK(x) Specifies the content of VRAM x address. - 161 -

ERROR MESSAGE 1. Display Format (1) When Command or Statement was directly entered, errors occurred: Message (2) When errors occur during text run; ? I Message"! error in | line No. (3) When error due to Input Statement is found in key Input Data: Message - 162 -

MESSAGE DESCRIPTION System System error due to Basic Interpreter Program. Generally this occurrence is impossible. N-formula too Complex Numeric values are too complicated. S-formula too Complex Character-String is too complicated. Overflow Values and operation results exceed permissible range. Division by Zero The denominator in division is 0. Function Parameter Function parameter is unusual. String too long The length of Character-String exceeds 255. Stack overflow Excessive use of parentheses ( ) . Patterns to PAINT are too complicated. User define function calls itself. Out of memory Memory is insufficient. Text. Variable. Array. Number of Subscripts Number of subscripts is unusual. Value of Subscript Value of subscript is improper. Syntax Syntax Error Command Parameter Command Parameter is unusal. Line number over In AUTO or RENUM, line No. Exceeds 65535. Illegal line number Line No. is improper. Line image too long Line image is too long, (RENUM, etc.) Undefined line number Line No. is undefined. (RENUM, GOTO, GOSUB, IF-THEN, RESTORE, RUN) Type mismatch The type of substituting side and that of substituted side do not match. (Values, strings) - 163 -

MESSAGE DESCRIPTION Out of DATA Reading by READ Statement was attempted but DATA of DATA statement is unavailable. RETURN without GOSUB RETURN statement was executed without GOSUB. GOSUB nesting GOSUB nesting exeeded 4 levels. NEXT without FOR For statement corresponding to NEXT is not available. FOR nesting FOR~NEXT nesting exceeded 4 levels. Statement Parameter Statement parameter is unusual. Can't continue Can't continue by CONT statement. FOR variable name FOR statement loop variable is not numeric variable. (Character string or array) Array name DIM statement parameter is not in array. Redimensioned array Dual array difinition was attempted. Undefined Array Erase of undefined array was attempted. No Program SAVE was attempted despite unavailability of program in text. Memory writing Memory writing error (At the time of LOAD) Device not ready Printer is not connected or in trouble. Undefined Function Undefined user function was called. Verifying Errors in comparison with tape programs. Illegal direct Direct statement run is impossible. - 164 -

MESSAGE DESCRIPTION Redo from start INPUT DATA of input statement is unusual. Redo input from the start. "Extra ignored INPUT DATA of input statement is unusual. Extra data was entered. Extra data was ignored. Unprintable Errors other than the above. - 165 -

SAMPLE PROGRAM CHECKERED PAINT 10 SCREEN 2,2: CLS 230 LINE (X , Y ) - ( XX , Y 50 X=10 : Y=10 : XX=250 : YY=190 240 Y=Y+20 100 REM VERTICAL LINE 250 NEXT 1 110 FOR 1=1 TO 12 300 REM PAINT 120 LINE (X,Y)-(X.YY),1 310 A=RND (1) *240 130 X=X+ 20 320 B=RND (1) *185 140 NEXT 1 330 C=RND (1) * 15 200 REM HORIZONTAL LINE 340 PAINT (A , B) , C 210 X=0 350 GOTO 300 220 FOR 1=1 TO 10 - 166 -

LINE 1 0 SCREEN2,2: C L S : C 0 L 0 R , 1 5 1 5 FOR l=0TO30 2 0 A= 1 N T ( R N D ( 1 ) * 1 6 ) 3 0 B = 1 N T ( R N D ( 1 ) * 1 2 8 ) : C = !1 N T ( R N D ( 1 ) * 9 6 ) 4 0 D = 1 N T ( R N D ( 1 ) * 2 5 6 ) : E = 1 N T C R N D ( 1 ) * 1 9 2 ) 5 0 LINE(B,C)- ( D , E ) , A , B 5 5 N E X T 1 1 0 0 GOTO 10 L I N E B F 1 0 SCREEN 2,2 C L S 2 0 A = 1 N T ( R N D ( 1 ) * 1 6 ) 3 0 B = 1 N T ( R N D ( 1 00 CM ) :: C = 1INT(RNDC1 )*96) 4 0 D = 1 N T ( R N D ( 1 ) * 2 5 6 ) :: E = 1INT(RND(1 )>i:192 5 0 L I N E ( B , C ) - ( D , E ) , A ,, B F 1 0 0 GOTO 20 - 167 -

C 1 R C L. E 1 1 0 SCREE N 2 , 2 : c L S : 2 0 FOR R = 1 T 0 9 6 3 0 C = 1 N T ( R N D ( 1 ) * 1 4 0 C 1 R C L E ( 1 2 8 i 9 6 ) 5 0 NEXT R 6 0 GOTO 2 0 C 1 R C L E 2 1 0 SCREE N 2 , 2 : C L S : 2 0 FOR R = 1 T 0 9 6 S T 3 0 C = 1 N T ( R N D ( 1 ) * 1 4 0 C 1 R C L E ( 1 2 8 9 9 6 ) 5 0 NEXT R 6 0 PAINT ( 0 , 0 ) 9 5 C 0 L 0 R 1 5 6 ) , R , C , 1 ,0,1 , C 0 L 0 R 1 5 E P 5 6 ) , R , C , 1 ,0,1 , - 168 -

CIRCLE 3 1 0 SCREE N 2 , 2 C L S 2 0 X = 1 N T ( R N D ( 1 ) * 2 5 6 ) 3 0 Y = 1 N T ( R N D ( 1 ) * 1 9 2 ) 4 0 C = 1 N T ( R N D ( 1 ) * 1 6 ; 5 0 R = 1 N T ( R N D ( 1 ) * 2 0 ) 6 0 C 1 R C L E ( X , Y ) » R , C 9 1,0,1 7 0 GOTO 2 0 B C I R C L E 1 0 SCREE N 2 9 2 : C L S : COLOR 1 5 2 0 FOR R = 1 T 0 9 6 S T E P 1 0 3 0 C = 1 N T ( R N D ( 1 ) * 1 6 ) 4 0 C 1 R C L E ( 1 2 8 , 9 6 ) , R , C , 1 9 0 5 0 NEXT R 6 0 FOR 1 = 9 1 T 0 1 S T E P - 1 0 7 0 B C 1 R C L E ( 1 2 8 9 9 6 ) , 1 9 9 1 9 0 8 0 N E X T 1 0 0 GOTO 2 0 - 169 -

Sprite Sample Program 1 0 M = 1 2 0 SCREE N 2 , 2 : C L S 3 0 MAG M C = R N D { 1 ) * 1 3 + 1 4 0 C U R S 0 R 1 0 , 1 0 ; P R 1 N T C H R $(17 ) MAG" 5 0 FOR Y = 0 T 0 1 9 1 S T E P 4 6 0 P A T T E R N S # 0 0 0 19 3 F 3 C 1 C 0 D 0 F 7 B II 7 0 P A T T E R N s # 1 0 C 0 F 0 F 0 F 0 7 0 3 1 B 0 7 11 8 0 P A T T E R N S # 2 0 0 C C F E 9 E 9 C D 8 7 8 E C 11 9 0 P A T T E R N S # 3 1 A F A F 8 F 0 E C 7 C 3 8 0 0 II 1 0 0 Y 1 = Y ; G 0 S U B 2 0 0 1 1 0 P A T T E R N s#o 0 0 19 3 F 3 C 1 C 0 D 0 F 1 B 11 1 2 0 P A T T E R N S # 1 2 C 2 F 0 F 0 7 1 B 1 F 0 E 0 0 II 1 3 0 P A T T E R N S # 2 0 0 C C F E 9 E 9 C D 8 7 8 E F II 1 4 0 P A T T E R N S# 3 1 8 F 8 F 8 F 8 F 0 6 0 6 C 7 0 II 1 5 0 Y 1 = Y + 2 : G 0 S U B 2 0 0 1 6 0 NEXT Y 1 7 0 M = M+ 2 ; 1 F M> 3 THEN M = 1 1 8 0 GOTO 2 0 2 0 0 SPRIT E 0 , ( 1 2 0 , Y 1 ) 0 , C 2 1 0 SPRIT E 0 , ( 1 2 0 , Y 1 + 1 ) , 0 C 2 2 0 R E T U R N - 170 -

PAINT 1 0 SCREEN2,2:CLS 2 0 FOR 1=0 TO 2 5 5 STEP 16 3 0 L 1 N E ( 1 , 0 ) - ( 1 , 1 9 1 ) : N E X T 1 4 0 FOR 1=0 TO 1 9 1 STEP 16 5 0 L 1 N E ( 0 , 1 ) - ( 2 5 5 > 1 ) : N E X T 1 6 0 C = 1 N T ( R N D ( 1 ) * 1 6 ) 7 0 X= 1 N T ( R N D ( 1 ) * 2 5 6 ) : Y = 1 N T 8 0 P A 1 N T ( X , Y ) , C 9 0 GOTO 60 1 ) * 1 9 2 ) END -17 1 -

John Sands