jmss89@ecs.soton.ac.uk (Scott JMS) (05/14/91)
Does anyone have any algorithms / assembler to implement file compression for the
Z80 CPU ?
I could do a port of stuff for 68000, but with 64k memory the hash tables tend to
gobble it all up - therefore I'd prefer something that didn't need hash tables
Please post to addresses below:
Thanks in advance
Jon Scott
------------
<jmss89@uk.ac.soton.ecs>
OR
<jon@uk.ac.leeds.geog>
------------ :-)michaelk@copper.WR.TEK.COM (Michael D. Kersenbrock) (05/23/91)
In article <7674@ecs.soton.ac.uk> jmss89@ecs.soton.ac.uk (Scott JMS) writes: >Does anyone have any algorithms / assembler to implement file compression for the >Z80 CPU ? > >I could do a port of stuff for 68000, but with 64k memory the hash tables tend to >gobble it all up - therefore I'd prefer something that didn't need hash tables > >Please post to addresses below: > >Thanks in advance > > Jon Scott > >------------ ><jmss89@uk.ac.soton.ecs> > OR > <jon@uk.ac.leeds.geog> >------------ :-) I once implemented 16-bit uncompress for the Z80 (CP/M). Even with heavy optimization and tricks (and with the "speed path" enhanced by "dropping" into assembly language), it still was VERY slow (output was a good bit faster than you could read, but it wasn't a blur either). My Z80 system had 1MB of RAM (but currently resides in a cardboard box in the garage somewhere). You *really* don't want to do it unless you'll be satisfied with a much smaller encoding. And it'll still likely go sluglike. -- Mike Kersenbrock Tektronix Logic Analyzer Division michaelk@copper.WR.TEK.COM Aloha, Oregon