RE: 8088 and 610 saga continues...

From: Hoffmann-Vetter, Martin <>
Date: Fri, 28 Jan 2011 18:32:07 +0100
Message-ID: <003d01cbbf11$4a2af6b0$>
Hello Michal,

> Now, let's apply this theory to our 8088 case... After careful
> isolation, I was able to determine that memory is corrupted after
> this call: 
> 0040:0674                 call    far ptr 0F000h:0F003h
> Which is, of course, a call to IPC. Until then, no 8088 code is
> executed from memory locations 0xxx21h nor 0xxxA1h.

Okay, now we know the programm code that corrupt the data.

> But in the ROM code at 0F000h:0F003... yes, we have an instruction at
> location 0FF021h, and guess what it is?
> F000:F021                 in	al,21h
> Now that's a coincidence - an instruction at location 21 which
> accesses port 21!

But that condition is running on the high profile boards. And this code is execute on the coprocessor board. The access to the rom isn't visable on the dram bus.



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Received on 2011-01-28 18:00:20

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