I wrote SALP (Structured Assembly Language Preprocessor) for 6502 code. This let me leverage an existing assembler rather than writing my own. SALP was written in SALP; the first version was tranformed by hand and after that it was used to develop itself. The commands are:

*! IF <condition ...

You can also look for Oric Lisp. Oric was a European 6502 computer.

BCD does not eliminate floating point errors; it merely changes them to different ones. Both binary and BCD can represent 1/2 exactly, but neither can represent 1/3 exactly.

I have an Apple II Integer BASIC disassembly at
http://linux.cis.monroeccc.edu/~paulrsm/6502/

One of the few bugs is the "TOO LONG" error message
instead of the "TOO MANY PAREN" error message.
This is caused by the byte at $E478 (or close) pointing
to the wrong error message.

The code at $E710 is ...

Excerpt from DTACK GROUNDED #27, January 1984

Chuck Peddle headed the CPU design team which designed the 6800 at Motorola. Motorola had DIFFERENT design teams working on the various peripheral chips such as the 6820, 6850 etc. After the 6800 design was completed and checked out, Motorola did NOT ...

A CF hard drive for the Apple II can be found at:

http://dreher.net/?s=projects/CFforAppl ... I/main.php

--
Paul

One should first write the routines for floating point add, subtract,multiply and divide and then write input output routines as above. This has obviously already been done for APPLE and COMMODORE with their BASIC systems. But probably not for the IEEE floating point format that nowadays is ...

"Machine Language for Beginners" can be found online at

http://www.atariarchives.org/

You may be able to copy and paste the BASIC code from that site.

For another version of the Woz FP routines with another explanation of the format, please see:

http://members.buckeye-express.com/mark ... FLOAT4.TXT

--
Paul
Monroe, Michigan USA

If you want to send me your 8KB binary file I can try my hand at disassembling it.

The Telemark Cross assembler (TASM) will output both Intel and Motorola hex formats.

See www.halcyon.com/squakvly/

Paul R. Santa-Maria
Monroe, Michigan USA

http://members.nbci.com/mkowalski.1/6502.html is now a dead page.

Paul R. Santa-Maria
Monroe, Michigan USA

My disassembler follows the code. It tracks the destination address of all jumps, JSRs, and branches. I do have to give it one valid code address. With 6502 ROMs I use the three vectors at the top of memory (RESET, IRQ, NMI). After the first pass, I look at the output for jump tables and add those ...

I've written a 65C02 disassembler in Turbo Pascal. It is a personal tool, not a commercial product, and it helps to have Turbo Pascal 7 for the multiple text windows (one for the program, one for the disassembly script, and one for the disassembler output). E-mail me for the program (binary and code ...

The early 6502s [pre June 1976 if I remember correctly] did not have the ROR instruction.

All 6502s up to the 65C02 had a bug with the JMP ($xxFF) instruction. The second byte [high byte] of the address was fetched from the same page [$xx00] instead of the next page [$xx00+$0100] of memory.

Paul R ...