Xref: utzoo comp.sys.intel:679 comp.arch:8055 comp.sys.ibm.pc:23923
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!gatech!gitpyr!is813cs
From: is813cs@pyr.gatech.EDU (Cris Simpson)
Newsgroups: comp.sys.intel,comp.arch,comp.sys.ibm.pc
Subject: Question for 8255 Guru
Message-ID: <7184@pyr.gatech.EDU>
Date: 30 Jan 89 00:55:41 GMT
Reply-To: is813cs@pyr.gatech.edu.UUCP (Cris Simpson)
Followup-To: comp.sys.intel
Distribution: usa
Organization: VA Rehab R&D | Ga Inst of Technology
Lines: 12


 I am having trouble figuring out the INTR abilities of the 8255A.
I understand that the 8255A signals the x86 on the INTR line, then
the x86 asserts INTA, and then reads the 'vector type' from
the data bus.  The question: How does the 8255A set up the byte
representing this 'vector type'?

Yes, I have RTFDataSheet.  No, please don't post responses, I'll
summarize if anyone cares.

Thanks,
cris