as a wild guess... I suppose the chip at $8000 is a Z80SIO it's programmed a bit like a crtc by writing 2 registers and I found a place in the code where they seem to send the reset of the chip the eprom is supposed to boot a network On 27/08/2020 13:41, groepaz_at_gmx.net wrote: > Am Donnerstag, 27. August 2020, 13:32:56 CEST schrieb Hans Liss: >> Odd code. It seems to have some magic I/O at $8000/$8001, with $8001 >> maybe producing side effects on read. >> >> Also, the sequence starting at $e7a0 is kinda epic. It laboriously >> stores code, instruction by instruction, at $0400 - $041b, and then >> jumps to $0400. I wonder why. > that would be the typical thing to do if you eg want to bank out the ROM you > are running from, to call code from another ROM (bank), or from RAM > > $400x seems to be I/O to me as well... there really must be more to this, ie > without the schematics or knowledge of the hardware it doesnt make a lot of > sense > > -- > > http://hitmen.eu http://ar.pokefinder.org > http://vice-emu.sourceforge.net http://magicdisk.untergrund.net > > If you can't beat them, join them. Family time can include playing a video > game. > <Dr. Ken Haller, Saint Louis University School of Medicine> > > > > >Received on 2020-08-27 14:04:36
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