23 Jan
2014
23 Jan
'14
8:56 p.m.
Picked up this critter yesterday, it's a short (~7") 8-bit ISA card made by
ATD (which the FCC sticker tells me is Advanced Transducer Devices) with a
female DB-25 and female DE9 connector on the rear edge.
There's a 40-pin IC on it labeled 'printer', as well as a 24-pin IC labeled
'mono', and a 6845 CRT controller. Fair enough, and initially I'm thinking
that it's just a reworked clone of an IBM MDA card - but also present on
the board are two 48-pin ICs, which suggests there might be more to it than
that; sure, I remember there being a lot of TTL logic on the IBM MDA board,
but I'm surprised it needs two 48-pin ICs to condense it all.
Unfortunately the pair of 48-pin chips are custom parts (as are the 'mono'
and 'printer' ICs) - one's branded ATD1/BLOWD/802D8643LD and the other
ATD2/WIND/8038637LDC.
Does anyone remember this board and can tell me if it is something more
than just MDA/parallel? There's no separate ROM chip, but I suppose it's
entirely possible that it has some firmware embedded in one of the large ICs.
cheers
Jules
23 Jan
23 Jan
9:11 p.m.
Jules Richardson wrote:
Picked up this critter yesterday, it's a short (~7") 8-bit ISA card made by
ATD (which the FCC sticker tells me is Advanced Transducer Devices) with a
female DB-25 and female DE9 connector on the rear edge.
There's a 40-pin IC on it labeled 'printer', as well as a 24-pin IC labeled
'mono', and a 6845 CRT controller. Fair enough, and initially I'm thinking
that it's just a reworked clone of an IBM MDA card - but also present on
the board are two 48-pin ICs, which suggests there might be more to it than
that; sure, I remember there being a lot of TTL logic on the IBM MDA board,
but I'm surprised it needs two 48-pin ICs to condense it all.
Unfortunately the pair of 48-pin chips are custom parts (as are the 'mono'
and 'printer' ICs) - one's branded ATD1/BLOWD/802D8643LD and the other
ATD2/WIND/8038637LDC.
Does anyone remember this board and can tell me if it is something more
than just MDA/parallel? There's no separate ROM chip, but I suppose it's
entirely possible that it has some firmware embedded in one of the large
ICs.
cheers
Jules
Don't kow this card, but when it has 64 Kbyte of RAM too, it may be a
Hercules compatible card.
Regards,
Holm
--
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Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
24 Jan
24 Jan
2:23 a.m.
On 01/23/2014 03:11 PM, Holm Tiffe wrote:
Don't kow this card, but when it has 64 Kbyte of
RAM too, it may be a
Hercules compatible card.
Oh, I'd not even considered that (obviously ;-) Unfortunately the only RAM
on the card is a CXK5816 IC, which is organized as 2048x8 - and it seems
that Hercules needs a shade under 32KB (720x348 @ 1bpp).
I suppose it's possible that there's additional SRAM within one of the
48-pin ICs, but I would have thought that unlikely (why design a custom IC
with half the memory needed for it to work, when you could just have fewer
pins and put all the memory off-IC)
cheers
Jules
2:40 a.m.
On 01/23/2014 08:23 PM, Jules Richardson wrote:
On 01/23/2014 03:11 PM, Holm Tiffe wrote:
And... scratch that. For some reason I blanked when looking at IC part
numbers and completely missed the pair of DRAMs. D'oh! :-( So, it does
have 64KB (in addition to the 2KB SRAM).
I've never had a Hercules board before, so it's a neat little find. I'm not
sure if I've got a monitor here that will work with it (but maybe an
adapter to convert between the TTL output and composite is trivial?) - but
it's on my 'want' list to find an IBM 5150 or 5160 again one day, and I
think the MDA display will work (?)
cheers
Jules
Don't kow this card, but when it has 64 Kbyte
of RAM too, it may be a
Hercules compatible card.
Oh, I'd not even considered that (obviously ;-) Unfortunately the only RAM
on the card is a CXK5816 IC, 
25 Jan
25 Jan
7:44 p.m.
I've never had a Hercules board before, so
it's a neat little find. I'm not
sure if I've got a monitor here that will work with it (but maybe an
adapter to convert between the TTL output and composite is trivial?) - but
Well, the adapter to a sort of composite video is not at all complicated.
The Hurcles card has a DE9 socket, same pinout and signals as an MDA.
BAsiclaly, 2 grounds,, 3 not used, video, intensity,m and 2 syncs. You
can combine the signals with an Xor gate and a couple of transistors.
But I said 'sort of composite video'. The point is what you will get out
of that is _NOT_ RS170 video. The horizotnal scan rate ofd the
MDA/Herculese is 18KHz or so, not the 15KHz of RS170. Not many monitors
will lock to it . You are probably better off finding a real MDA monitor,
the can't be that rare yet (or are they???)
it's on my 'want' list to find an IBM 5150
or 5160 again one day, and I
think the MDA display will work (?)
YEs,the IBM 5151 MDA monitor will work.
-tony
23 Jan
23 Jan
9:20 p.m.
On 1/23/14 12:56 PM, Jules Richardson wrote:
Picked up this critter yesterday, it's a short (~7") 8-bit ISA card made by ATD
(which the FCC sticker tells me is Advanced Transducer Devices) with a female DB-25 and
female DE9 connector on the rear
edge.
There's a 40-pin IC on it labeled 'printer', as well as a 24-pin IC labeled
'mono', and a 6845 CRT controller. Fair enough, and initially I'm thinking
that it's just a reworked clone of an IBM MDA
card - but also present on the board are two 48-pin ICs, which suggests there might be
more to it than that; sure, I remember there being a lot of TTL logic on the IBM MDA
board, but I'm surprised it
needs two 48-pin ICs to condense it all.
Unfortunately the pair of 48-pin chips are custom parts (as are the 'mono' and
'printer' ICs) - one's branded ATD1/BLOWD/802D8643LD and the other
ATD2/WIND/8038637LDC.
Does anyone remember this board and can tell me if it is something more than just
MDA/parallel? There's no separate ROM chip, but I suppose it's entirely possible
that it has some firmware embedded in
one of the large ICs.
Sounds more like a Hercules clone.
3990
days inactive
3992
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5 comments
4 participants
participants (4)
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aek＠bitsavers.org -
ard＠p850ug1.demon.co.uk -
holm＠freibergnet.de -
jules.richardson99＠gmail.com