by Oscar Toledo G. https://nanochess.org/
This a BASIC language for the Intellivision Entertainment Computer System. I intend to make it as a (better) replacement for the incredibly slow and limited Intellivision ECS BASIC.
I wrote an article in two parts about its development, you can read part1 here, part2 here, and an Atariage thread
It is written in CP1610 assembler language, and it has been tested both in emulation and with real hardware.
For example, this program runs in 15 seconds (modified from a benchmark by carlsson):
The same program for the Mattel ECS BASIC takes 210 seconds:
The PRINT of the benchmark exists only to stop your chronometer, because all these multiplications exceed the limits of the floating-point format.
There are 26 variables (A-Z), 26 string variables (A$-Z$), and 26 unidimensional arrays (A-Z) requiring DIM first to declare them.
The floating-point support is 32 bits (25-bit mantissa, 7-bit exponent, and sign bit). Number input and output support scientific notation.
The following statements are supported:
LIST
LIST line
LIST line-
LIST line-line
LLIST
RUN
RUN line
NEW
LOAD "file"
SAVE "file"
VERIFY "file"
REM comment
DIM a(length)
DIM a(length),b(length)
v = expr
IF expr THEN line
IF expr THEN statement
IF expr THEN statement ELSE statement
GOTO line
STOP
INPUT v
INPUT v$
INPUT a(i)
INPUT "string";v
INPUT "string";a(i)
INPUT "string";v$
LPRINT
PRINT expr
PRINT expr$
PRINT "string"
PRINT "string";
PRINT "string";expr
PRINT "string";expr$
PRINT TAB(5);"string"
PRINT SPC(5);"string"
PRINT AT 20
PRINT AT 20;"string"
GOSUB line
RETURN
FOR v=x TO y
FOR v=x TO y STEP z
FOR a(i)=x TO y
NEXT
NEXT v
RESTORE
RESTORE line
READ v
READ v,v
READ a(i)
READ a$
READ a$,b$
DATA n
DATA n,n
DATA "string"
COLOR expr
SPRITE [0-7],x,y,c
SOUND 0,[f][,v]
SOUND 1,[f][,v]
SOUND 2,[f][,v]
SOUND 3,[f][,env]
SOUND 4,[noise][,mix]
WAIT
bk(pos)=card
MODE 0,colors
MODE 1
BORDER color
DEFINE card,"hex.drawing"
POKE addr,expr
ON expr GOTO line1,line2,line3
ON expr GOSUB line1,line2,line3
PLOT x1,y1,color
DRAW x2,y2,color
CIRCLE x1,y1,radius,color
Statements can be concatenated on a single line using the colon as a separator.
The following expression operators are supported:
OR
XOR
AND
=
<>
<
>
<=
>=
+
-
*
/
^
-expr
NOT expr
(expr)
num
v
a(index)
INT(expr)
ABS(expr)
SGN(expr)
RND
STICK(cont)
STRIG(cont)
KEY(cont)
BK(pos)
PEEK(addr)
USR(addr)
ASC(str)
LEN(str)
CHR$(expr)
LEFT$(str,length)
MID$(str,pos)
MID$(str,pos,length)
RIGHT$(str,length)
VAL(str)
STR$(expr)
INKEY$
INSTR(str1,str2)
INSTR(pos,str1,str2)
SIN(expr)
COS(expr)
TAN(expr)
LOG(expr)
EXP(expr)
SQR(expr)
ATN(expr)
TIMER
FRE(expr)
POS(expr)
LPOS(expr)
POINT(x,y)
HEX$(expr)
COL0
COL1
COL2
COL3
COL4
COL5
COL6
COL7
String support allows comparison between strings, string concatenation, and assorted functions. There's no support for arrays of strings nor bidimensional arrays.
If you get an error, you can do debugging of the program by using PRINT to see the variables, and using GOTO to re-enter a program. RUN resets all variables.
The editor is full-screen, this means you can move the cursor up to the line you want to correct or edit, and type over it, and press Return to change it. Or in other words, you don't need to retype a BASIC line, just LIST it, edit it, and press Return.
Given the slow speed of the CP1610 processor, the interpreter doesn't allow expressions for the target line of GOTO and GOSUB statements.
A small game in this flavor of BASIC:
10 CLS:REM UFO INVASION. NANOCHESS 2025
20 DEFINE 0,"183C00FF007E3C000018183C3C7E7E000000183C3C3C3C7EFF2400"
50 x=96:w=0:v=0:u=0:t=159
60 SPRITE 0,776+x,344,2061
70 SPRITE 1,776+v,256+w,2066
80 SPRITE 2,1796+t,256+u,6149
90 WAIT:c=STICK(0)
100 IF c>=3 AND c<=7 THEN IF x<152 THEN x=x+4
110 IF c>=11 AND c<=15 THEN IF x>0 THEN x=x-4
120 IF w=0 THEN SOUND 2,,0:IF STRIG(0) THEN v=x:w=88
130 t=t+5:IF t>=160 THEN t=0:u=INT(RND*32)+8
140 IF W=0 THEN GOTO 60
150 SOUND 2,W+20,12:W=W-4
160 IF ABS(w-u)<8 AND ABS(v-t)<8 THEN t=164:w=0:GOSUB 180
170 GOTO 60
180 SOUND 3,8000,9:SOUND 1,2048,48
190 RETURN
This game can be loaded using the jzintv emulator and the provided tape_UFO.ecs file from the utils directory.
You can load the ROM in a JLP-Flash cartridge for running the BASIC interpreter on a real Intellivision. You need the Mattel Intellivision ECS, as this peripheral provides the computer keyboard.
If you are using any other Flash cartridge, be sure to enable 16-bit RAM memory in the area $8000-$9fff (8K words). Most cartridges implement it as CC3 memory (Cuttle Cart 3) because it was the first to provide it.
The LOAD, SAVE, and VERIFY statements are working in emulation and real hardware. Filenames are four characters (just to keep an small compatibility with the ECS tape format, and because the jzintv emulator can separate different files in the main directory)
For real hardware, instead of cassette, you can use a PC computer and connect the "To tape" connector to the Mic input, and the "From tape" connector to the Line Out. I recommend using Audacity to handle the recording and playing. You need to amplify the recorded signal, Audacity chooses automatically the maximum level possible. It is suggested to save your recordings as WAV files.
The LPRINT, and LLIST statements are working in real hardware using a Mattel Aquarius printer. Never tested in emulation, because jzintv has a bug.
If your printer doesn't come with the cable, here is a schematic of how you can build one: https://forums.atariage.com/topic/323929-aquarius-printer-technical-info-and-reverse-engineering/
I've started a thread in Atariage to publish games made with my interpreter.
- Hangman.
- Lunatic Math.
- Dogfight.
- Spider Invasion.
- Aircraft.
- Parachute.
- Chalice.
- Meteors.
- Road Race.
I've published a small booklet (33 pages) containing a full reference of the language, and includes the nine games for your typing pleasure.
It is available from lulu.com
