Newsgroups: comp.sys.oric
Subject: TAP file viewer and 6502 "decoders"
Date: Sat, 10 Aug 2002 12:35:46 +0200
Message-ID: <slrnala8qq.ds.amajorel@atc5.vermine.org>

> > As I cannot get my ORIC emulator to display on my TFT screens I wonder
> > if there is any other way to view TAP files and potentially the 6502
> > code embedded in them (as I recall it I think it was done in DATA
> > statements?) in Win98 environment.
> >
> > Also, do you know if there exist a 6502 "decoder" (or whatever the
> > terminology is) to view old #code (in the DATA statemements) in a more
> > readable ASSY-format?
> 
> I don't think there exists anything that goes straight from
> machine-code-in-DATAs-in-a-BASIC-program-in-a-.tap-file to
> disassembly listing. However, bas2txt will do the first third of
> the job (converting the .tap to a text file). Marko Mäkelä's d65
> will do the last third by disassembling 6502 machine code.
> 
> What's missing is the glue that will convert BASIC DATAs to a
> binary image suitable for d65. That can probably be done with
> Perl (or whatever your scripting language of choice is).

You'll find one at the end of this post. Here's how it's used :

  $ bas2txt chess-ii.tap
  $ grep DATA chess-ii.txt
  8100 DATA#2000,#221B,#26C5,#28B0,#2BFD,#30AC,#3385,#35B4,#37F0,#3D53,#419A
  8105 DATA#430F,#4907,#4B8E,#4E3E,#51F1,#565E,#5D50,#5F18,#6182
  $ ./oricdadu chess-ii.txt >chess-ii.data
  $ atdump chess-ii.data
  0000 0000  00 20 1B 22-C5 26 B0 28-FD 2B AC 30-85 33 B4 35  . ."Å&°(ý+¬0.3´5
  0000 0010  F0 37 53 3D-9A 41 0F 43-07 49 8E 4B-3E 4E F1 51  ð7S=.A.C.I.K>NñQ
  0000 0020  5E 56 50 5D-18 5F 82 61                          ^VP]._.a

It's very crude. It supports only three data types : unsigned
bytes in decimal (0-255), bytes in hex (#00-#FF) and words in
hex (#0000-#FFFF). Everything else is rejected with a warning
message.

If you're going to use this on a non-Unix OS, you should use -o
instead of redirecting standard output, as standard output is in
text mode by default (causing 0A -> 0D0A corruption).