Re: Commodore PLC TIB DD-001 / Drive 2001

From: Ruud_at_Baltissen.org
Date: Mon, 19 Nov 2018 19:12:19 +0100
Message-ID: <5BF2FD03.509.38312E@Ruud.Baltissen.org>
Hallo allemaal,


I'm back from Poland. And my parents-in-law still don't have 
internet (and will never get it). And no Wifi at all in the 
neighbourhood. So that's why I'm reacting only now.


> I was indeed thinking about soldering one using an 
> ordinary 765. 

Which isn't a good idea at all in the end. I completely forgot that 
the old 765 needs a lot of additional ICs, just have a look at an 
original IBM controller board.
But I do have some UM8397s that claim to be PC compatible (read 
NEC-765 compatible). Looking at the datasheet, the description looks 
familiar. The commandset, including the structure of the commands, 
looks the same as both the NEC-765 and 82C765B IMHO. 



Hallo Konrad,


> I have attached my initial disassembly using White Flame's ...

I will have a look at it.


> ... I could not find all the commands. 

Weird, all 15 commands are given in a row, complete with the needed 
structure. That is, in the datasheet I have. 
What is more frustrating, I have no idea how the TID handles all 
commands. So far, I think, I have only found a set of bytes that 
looks like the set needed to handle the read command. Then what 
about the rest?
Even more frustrating: I thought about using a commented source of 
the BIOS of the IBM PC and one of a clone. But both didn't clarify 
things at all. For example, the "Read command" needs nine bytes to 
be sent to the 765. I can only find three. So what about the rest 
???
And then there is a lot of exchanging data with the cassette buffer: 
reading, storing, adding, comparing and what ever alse is possible. 
But without a decent start yet, I have no idea where all that is 
meant for. Hopefully in time I will find out....


--
   
Kind regards / Met vriendelijke groet, Ruud Baltissen
www.Baltissen.org







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Received on 2018-11-19 20:00:07

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