Software:Galaksija BASIC

Galaksija BASIC

Developer(s)	Microsoft, Voja Antonić
Initial release	1983 (1983)
Platform	Galaksija
Type	Microsoft BASIC

Galaksija BASIC was the BASIC interpreter of the Galaksija build-it-yourself home computer from Yugoslavia. While being partially based on code taken from TRS-80 Level 1 BASIC, which the creator believed to have been a Microsoft BASIC, the extensive modifications of Galaksija BASIC—such as to include rudimentary array support, video generation code (as the CPU itself did it in absence of dedicated video circuitry) and generally improvements to the programming language—is said to have left not much more than flow-control and floating point code remaining from the original.

The core implementation of the interpreter was fully contained in the 4 KiB ROM "A" or "1". The computer's original mainboard had a reserved slot for an extension ROM "B" or "2" that added more commands and features such as a built-in Zilog Z80 assembler.

ROM "A"/"1" symbols and keywords

The core implementation, in ROM "A" or "1", contained 3 special symbols and 32 keywords:

!

begins a comment (equivalent of standard BASIC REM command)

#

Equivalent of standard BASIC DATA statement

&

prefix for hex numbers

ARR$(n)

Allocates an array of strings, like DIM, but can allocate only array with name A$

BYTE

serves as PEEK when used as a function (e.g. PRINT BYTE(11123)) and POKE when used as a command (e.g. BYTE 11123,123).

CALL n

Calls BASIC subroutine as GOSUB in most other BASICs (e.g. CALL 100+4*X)

CHR$(n)

converts an ASCII numeric code into a corresponding character (string)

DOT x, y

draws (command) or inspects (function) a pixel at given coordinates (0<=x<=63, 0<=y<=47).

DOT *

displays the clock or time controlled by content of Y$ variable. Not in standard ROM

EDIT n

causes specified program line to be edited

ELSE

standard part of IF-ELSE construct (Galaksija did not use THEN)

EQ

compare alphanumeric values X$ and Y$

FOR

standard FOR loop

GOTO

standard GOTO command

HOME

equivalent of standard BASIC CLS command - clears the screen

HOME n

protects n characters from the top of the screen from being scrolled away

IF

standard part of IF-ELSE construct (Galaksija did not use THEN)

INPUT

user entry of variable

INT(n)

a function that returns the greatest integer value equal to or lesser than n

KEY(n)

test whether a particular keyboard key is pressed

LIST

lists the program. Optional numeric argument specifies the first line number to begin listing with.

MEM

returns memory consumption data (need details here)

NEW

clears the current BASIC program

NEW n

clears BASIC program and moves beginning of BASIC area

NEXT

standard terminator of FOR loop

OLD

loads a program from tape

OLD n

loads program to different address

PTR

Returns address of the variable

PRINT

Printing numeric or string expression.

RETURN

Return from BASIC subroutine

RND

function (takes no arguments) that returns a random number between 0 and 1.

RUN

runs (executes) BASIC program. Optional numeric argument specifies the line number to begin execution with.

SAVE

saves a program to tape. Optional two arguments specify memory range to be saved (need details here).

STEP

standard part of FOR loop

STOP

stops execution of BASIC program

TAKE

replacement for READ and RESTORE. If the parameter is variable name, acts as READ, if it is number, acts as RESTORE

UNDOT x, y

"undraws" (resets) at specified coordinates (see DOT)

UNDOT *

Stops the clock, not part of ROM

USR

Calls machine code subroutine

WORD

Double byte PEEK and POKE

ROM "B"/"2" additional symbols and keywords

The extended BASIC features, in ROM "B" or "2", contained one extra reserved symbol and 22 extra keywords:

• %
• /LABEL
• ABS(x)
• ARCTG(x)
• COS(x) COSD(x)
• DEL
• DUMP
• EXP(x)
• INP(x)
• LDUMP
• LLIST
• LN(x)
• LPRINT
• OUT
• PI
• POW(x,y)
• REN
• SIN(x), SIND(x)
• SQR(x)
• TG(x) TGD(x)

See also

• Voja Antonić, creator of Galaksija and this BASIC

External links

• Uputstvo za upotrebu, user manual online, complete, original, in Serbian language