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JGardner
October 11th, 2011, 06:51 AM
I should've mentioned ASM2B74 is available on WHTech, thanks
presumably to Charlie Good, whom I sent a bunch of stuff many years
ago. It's a bit rough around the edges - In particular, IIRC, the "B74"
file it produces may contain null lines which TIC74 will choke on - So
remove them... :) NLR.EXE works too.

Or you might try this more recent version, which encodes the pgm bytes
as ASCII char values in the DATA statement(s), hence is noticeably more
economical of memory.

In this scheme each DATA line is read as a string, then deconstructed into
into individual values and poked into memory, perhaps as follows...

100 DATA #b& (_ ...
110 READ A$
115 ADDR = 16384
120 FOR N = 1 TO LEN (A$)
130 BYTE = ASC ( SEGS$(A$, N, 1) )
140 CALL POKE ( ADDR, BYTE )
150 ADDR = ADDR + 1
160 NEXT N

GETMEM.SUB can be used to reserve memory for your routine so BASIC data
structures don't get overwritten; an interesting alternative, if you have a RAM
cartridge, is to use un-appended cartridge RAM to store your program/data.

The example above assumes the presence of an 8/32K cartridge which has NOT
been appended to system RAM with ADDMEM/MEMADD. The advantage is that
data thus stored is fairly likely to survive a system crash or reset....

Anyway -

The file produced by L2D is a .PGM file, not a .B74 file, because opening such a
B74 file in an ordinary editor may corrupt the file - The editor may interpret chars
in the DATA statements as control characters. Be sure to SAVE your work as a
.PGM file before experimenting.

I've noticed files posted on the net sometimes "evolve". If what you download
does'nt work, please contact me for an unexpurgated :) or current version.

Bug reports/comments/suggestions also welcome.

Jack

Ksarul
October 13th, 2011, 07:48 PM
Thanks for the update, Jack!