[sebhc] H8 Emulator update

Dave Dunfield dave04a at dunfield.com
Sun May 30 11:31:55 CDT 2004

Hi Stevem.

>>I've provided ... a bootable HDOS disk image in the file HDOS16.H8D.
>Why not provide HDOS 2.0 instead?   It's the last of the (Heath) HDOS 

Two reasons: 1) The HDOS1.6 disk has the assembler on it (as well as edit
and BASIC) - since the disks are big I don't want to have to include too
many of them. 2) The HDOS 2.0 drivers have the softare timing loop issue
which prevents booting it in "bat out of heck" mode.

>>You can use the /I command option force the simulator to ignore the bad 
>Does it still just ignore?  Or does it cause all opcodes to behave like a 
>real 8080?  (like the other codes for jmp, ret, call, etc).  It would be 
>nice to have a "real 8080" mode if /I doesn't do it.

Not currently - it's doable, but why are you so concerned about invalid
opcodes? - I won't think this should be an issue (except of course for the
HASL thing - which is a NOP in disguise). Did Heath use the other undoced

>(and you're missing the word "to" between "option" and "force")


>>!PAM-8 GO monitor
>This format is different from the other .HEX's.  I don't recognize it, what 
>is it?

It's Motorola hex download format - My tools (and H8) accept either format,
and produce either, however Motorola format by default due to the fact that
I've spent a lot more time working with Motorola MCU's, and also I think it's
a bit cleaner.

dave04a (at)    Dave Dunfield
dunfield (dot)  Firmware development services & tools: www.dunfield.com
com             Vintage computing equipment collector.

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