I wrote...
> Looks like I'll have to get my hands dirty with some Z80 at the
> weekend...

And I have!

The patched ROM3 is ready. By removing the rainbow stripes and the copyright
message I freed up 130 bytes and just managed to squeeze my new code in the
ROM to first check that the Trinity Ethernet Interface is connected then
fetch in a 1K bootblock from the Trinity's 128K EEPROM and execute it.

I've just got a simple test routine stored in the EEPROM for the time being
so I could check it was all working, but the next step is to write code so
it can then fetch in the full DOS from the EEPROM too which should be a
relatively straightforward task to write. Of course though the 1K bootblock
in the EEPROM could contain whatever you want so there's nothing stopping
anyone else to write their own code to pop in the EEPROM to execute on
startup.

I'll be writing up all what I've done for the next SAM Revival magazine and
including all the source code for the ROM patch, the finished bootblock and
installer for getting it to load DOS on startup. There'll also be some
skeleton code for creating your own bootblock routine for it to execute on
startup.

I've got some EPROM chips on the way so will have the new ROMs available
later this week.

Colin
=====
Quazar : Hardware, Software, Spares and Repairs for the SAM Coupe
1995-2009 - Celebrating 15 Years of developing for the SAM Coupe
Website: http://www.samcoupe.com/

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