Can anyone identify this S100 serial board?

[ethan at 757.org]

/me bows

"National Multiplex" is the brand! Thanks Glitch!


> I've got the manual for this one -- I've got one myself. I'll get it
> scanned and uploaded.
>
> Thanks,
> Jonathan
>
> On Tue, Jul 10, 2018 at 10:20 PM, Richard Cini via cctalk <
> cctalk at classiccmp.org> wrote:
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>>         The two connectors at the top remind me of the MITS 2SIO board.
>> Chip on the left with the label seems odd — looks like an EPROM. Not sure
>> why they’d use a UART (40-pin chip) and an ACIA, but it’s an interesting
>> two-port combo board.
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>>         Get Outlook for iOS
>>
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>> On Tue, Jul 10, 2018 at 10:17 PM -0400, "dwight via cctalk" <
>> cctalk at classiccmp.org> wrote:
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>> I'm thinking one serial and one cassette. The 8251 for the cassette.
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>> I can't make out all the chips at the pins? The board was hand laid out.
>> Is there nothing on the bottom but traces?
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>> Dwight
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>> ________________________________
>> From: cctalk  on behalf of Ethan via cctalk
>> Sent: Tuesday, July 10, 2018 6:43:12 PM
>> To: cctalk at classiccmp.org
>> Subject: Can anyone identify this S100 serial board?
>>
>>
>> Trying to identify the S100 serial board in my Imsai 8080.
>>
>> https://imgur.com/eZyOVT5
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>> I assume it was a kit. There are wires from behind one of the ICs that go
>> to DB25 on the rear, along with other DB25s with a few pins (maybe
>> cassette input.)
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>> Any help appreciated.
>>
>>
>> --
>> : Ethan O'Toole
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--
: Ethan O'Toole