Query for dec teleprinter roms
billdegnan at gmail.com
Mon Sep 21 14:19:22 CDT 2015
What are you going to do with these? Is there a ROM archive for DEC
On Mon, Sep 21, 2015 at 3:14 PM, Jonathan Gevaryahu <jgevaryahu at gmail.com>
> Does anyone have an LA36, LA120 or LAS12, LA34, LA100, or LA210 somewhere
> which they could dump the ROMs from?
> The LA36 uses several proms for its discrete cpu, and 2 character set roms
> which I believe have an 'odd' pinout.
> The LA120, one of the roms on the '2 rom version' is an 8k 2364 24 pin
> chip which is a bit annoying to dump, since you either need a 2364->2764
> 24->28 pin adapter, or (better) a programmer which can dump MC68764 or
> MC68766 24-pin 8k eproms (which have the same pinout as 2364). The other
> rom on the 2 rom version is a 2k 2316 24 pin chip.
> The oldest LA120 version uses 5 roms, all 2k 2316s. The code on the 5-rom
> version and the 2-rom version may very well be the same (the first 4 2k
> chips consolidated to one 8k chip), I'm not sure. Would be nice to get
> dumps of both versions.
> The LAS12 uses different code from the LA120 and to the best of my
> knowledge all LAS12s use 2 roms, one 8k and one 2k.
> LA34, theres at LEAST five firmware versions, almost certainly six, and
> possibly as many as seven. There is also a special firmware for a 'rom
> expansion' daughterboard.
> The 1978 LA34 "54-13374" motherboard has a bizarre Intel i8355 mask rom+io
> chip in it, plus a separate rom as well. (there are at least two versions
> of said i8355+rom firmware). Dumping the i8355 is not for the faint of
> heart, it would likely be easier to insert a 'dumping program' eprom into
> the single rom's socket, and use the LA34's cpu to spit its own rom
> contents out via serial.
> The 1980 LA34 "54-13747" motherboard lacks the i8355 and uses 2 or 3 mask
> roms or eproms on it instead (and 74xx logic for the i/o). There are at
> least three rom revisions for this, possibly four or five.
> LA100 (AKA LW100)... I have no idea. There's definitely at least one rom
> revision. Also to the best of my knowledge neither the maintenance print
> set nor the technical manual for the LA100 are scanned (they certainly
> don't appear at http://bitsavers.trailing-edge.com/pdf/dec/terminal/la100/
> ), which makes it difficult to know.
> Jonathan Gevaryahu
> jgevaryahu at gmail.com
> jgevaryahu at hotmail.com
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