Applesoft Lite - Applesoft BASIC for the Replica-1

Applesoft Lite: Applesoft BASIC for the Replica-1

Applesoft Lite is a modified version of Applesoft BASIC from the Apple II, designed to run on the Replica-1.

The modifications were made by disassembing the Applesoft ROMs from an Apple II+ and using the S-C DocuMentor as a guide. Apple II specific things (like graphics) have been removed, and a few Apple-1/Replica-1 specific things have been added.

Supported tokens:
FOR/NEXT, DATA/READ/RESTORE, INPUT, DIM, CALL, HIMEM/LOMEM, ONERR/RESUME, LET, GOTO, RUN/STOP/CONT, IF/THEN, GOSUB/RETURN/POP, END, REM, ON, POKE, PRINT (or "?"), LIST, CLEAR, GET, NEW, TO, SPC, NOT, STEP, +, -, *, /, ^, AND, OR, >, =, <, SGN, INT, ABS, FRE, SQR, RND, LOG, EXP, PEEK, LEN, STR$, VAL, ASC, CHR$, LEFT$, RIGHT$, MID$

Unsupported tokens:
Graphics: TEXT, GR, HGR, HGR2, PLOT, SCRN, HLIN, VLIN, COLOR=, HPLOT, DRAW, XDRAW, HCOLOR=, ROT=, SCALE=
Cassette I/O: STORE, RECALL, SHLOAD (*See also LOAD and SAVE, below)
Text Stuff: HOME, HTAB, VTAB, POS, TAB, NORMAL, FLASH, INVERSE, SPEED=
Math Stuff: COS, SIN, TAN, ATN
Other: DEL, TRACE, NOTRACE, PR#, IN#, WAIT, DEF/FN, USR, & (ampersand), PDL

New tokens in Applesoft Lite
CLS - Clears the screen by writing 24 carriage returns, but leaves the cursor at the bottom.
LOAD, SAVE - Store programs on a CFFA1 CompactFlash card! The LOAD and SAVE commands accept a filename as a parameter (e.g., "SAVE MYPROGRAM")
MENU - A shortcut to launch the CFFA1's built-in menu.

Notes:

Tokenized Applesoft files from an Apple II will not work, nor will Applesoft Lite files work on an Apple II. If you'd like to try and load an Apple II program, use the source listing rather than a SAVEd file. Unsupported tokens will result in syntax errors.

Tokenized Integer files will not work either, but the source code may work to some degree.

For the LOAD and SAVE commands, filenames containing BASIC token names are parsed incorrectly, resulting in an error. For example, you can't 'SAVE PRINT'. This should be fixed in a future release.

The RAM version requires 32K of RAM ($0000-$7FFF), and the ROM version requires 8KB of ROM ($E000-$FFFF).

The RAM version is reported to work on the Obtronix Apple-1 clone with a CFFA1 card installed.

Downloads:

ROM Version
This version is a ROM image which is ready to be programed in to a 28C64 EEPROM (or equivalent) for the Replica-1's ROM socket. It replaces Integer BASIC and the Krusader assembler, but maintains the original Woz monitor. Applesoft is loaded at $E000.

Applesoft Lite ROM image version 0.4 (8KB)

** NEW! ** RAM Version
This version runs from RAM, eliminating the need to swap ROMs. It loads at $6000 but should be functionally identical to the ROM release. The length is 7,885 ($1ECD) bytes. The hex dump is over 25KB, so it will take several minutes to load it via the serial port.

Applesoft Lite RAM image version 0.4 (7.8KB)
Applesoft Lite RAM hex dump version 0.4 (25KB)

Source Code
Source code is available as well. I have been doing all builds using the ca65 assembler from the cc65 package. The source package includes a makefile which will assemble and link the ROM image. The modifications for RAM version have not been added to the source package yet.

Applesoft Lite ROM source code version 0.4 (45KB)

Github repository: https://github.com/txgx42/applesoft-lite

Please consider this to be preliminary and subject to change, and possibly broken since it hasn't been thoroughly tested yet. Feedback is welcome, stop by the Briel Computers Forum!

Last Updated: 5-October-2008