[vcf-midatlantic] Latest toy(s)

Neil Cherry ncherry at linuxha.com
Tue Nov 19 13:20:32 EST 2019

On 11/19/19 11:19 AM, Herb Johnson via vcf-midatlantic wrote:
>> [ebay] for 2 1979 Motorola 68B09 boards (looks to be an Exorset
>> board).
> Neil, I think you and I have talked about these boards before, and I saw the auction. I 
> have an EXORbus system myself and some interest otherwise in these early 8-bit busses. 
> Consider bringing a board for some show-and-tell at Festivus; we can figure it out and 
> show how that used to be done.

I'll bring a bunch of boards (geek pron) but none are for sale (Keeps your
mittens off my 8 bittens ;-) Hey I'm an engineer not a poet).

I've actually spoken about these and a few others. The one I missed was
the incredible one with the trick op code insertion and the 2K of DAT
(a more advance version of the 74189 built DAT). I actually heard about
that one back in the 80's. Always thought that was so cool.

I'm also up for some reverse engineering learning. I have a board I helped
design (a 6809 board) that I don't think I have the PAL equations for any
more. That blank board seems to be quite tricky as a trace with a voltmeter
on address bus doesn't seem to go where I expected it would.

The set I just got are the simple Motorola reference design (or close
to it). I suspect it won't take much to get ASSIST09 on the board.

 > Regards, Herb "we don't need no steenking schematics" Johnson

Actually walking the high 4 bits of the address lines will probably
give us the start of the memory map by checking the chip select. As
long as they didn't get to funky with clock matching. That can add
to the fun.
Linux Home Automation         Neil Cherry       ncherry at linuxha.com
http://www.linuxha.com/                         Main site
http://linuxha.blogspot.com/                    My HA Blog
Author of:    	Linux Smart Homes For Dummies

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