[sebhc] H17 ROM ?

[Dwight K. Elvey]

>From: "Steven Parker" <sp11 at hotmail.com>
>
>Dwight says:
>>  The other file he should look at, if he is going to trap
>>I/O is H17def.acm.
>
>That's one of the "associated header files" I was referring to.  :-)
>
>>Also, one of the two, u8250.acm or u8251.acm.
>>I forget which was on the H17 card. I think it was the 8251.
>
>No, those are both I/O card chips (8250 in the H8-4, 8251 in the H8-5).
>The H17 uses a S2350 USRT.  Those are the ports defined in h17def.acm.

Yep, now I remember.

>
>>There was a timing error
>>... for someone doing direct calls to
>>the ROM, one should be aware of this.
>
>Yea, if you were writing 8080 code to USE the disk.   Not if you're writing 
>PC code to EMULATE the disk.  :-)

 I guess an emulator wouldn't have this problem.
 Later
 Dwight
 
>
>Cheers,
>
>- Steven


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