KLund1 Posted September 1, 2019 Share Posted September 1, 2019 Hello, I just came across this card for 800's. I think it is a serial & parallel port card. Or maybe for the old style IBM hard drives that needed 2 ribbon cables. I can't find anything in a quick google search. Anyone know anything about this card? 7 Quote Link to comment Share on other sites More sharing options...
JR> Posted September 1, 2019 Share Posted September 1, 2019 (edited) A real rarity! Edited September 1, 2019 by JR> Quote Link to comment Share on other sites More sharing options...
BillC Posted September 1, 2019 Share Posted September 1, 2019 8 minutes ago, KLund1 said: Or maybe for the old style IBM hard drives that needed 2 ribbon cables. Those drives were MFM or RLL, I still have 2 ST251 40MB MFM drives. Quote Link to comment Share on other sites More sharing options...
KLund1 Posted September 2, 2019 Author Share Posted September 2, 2019 I guess Curt says they are rare. Only a few made. I guess I have most of them. My source got them from an Atari engineer. If I recall, my source said his name was Dave. Maybe the same person Curt got his stuff from, maybe not. Maybe he 'found more in the back'. I got the PBI test board, and the 3-Bit 80 column card, and some 32K ram cards from him too. The more I dig into my sources stuff the more goodies I find. He has a lot of fruit, leather tanning, calculator maker, and some huge mainframe companies' junk I have to get past, though 6 Quote Link to comment Share on other sites More sharing options...
KLund1 Posted September 2, 2019 Author Share Posted September 2, 2019 Another friend has 2 of those 8" drive cards mentioned in post #2. One with a drive connected and the driver disk. Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted September 2, 2019 Share Posted September 2, 2019 It would be nice to see hi-res pics of the circuit board (both sides) and chips. This may prove to be useful if anyone ever takes up the idea of the 890 expansion box. Quote Link to comment Share on other sites More sharing options...
KLund1 Posted September 2, 2019 Author Share Posted September 2, 2019 Are these high res enough? It is about the best I an do right now. 2 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted September 2, 2019 Share Posted September 2, 2019 (edited) Yes it is a serial and parallel card, looks for the disks as well I think were 2. Enough were made to make it to the East. Not a crazy number of people had them though. It should be 1 serial port and 2 parallel ports... the ribbon cables were special in that is split the connector into 2 parallel ports... shouldn't be to hard to recreate. your board is missing a number of chips (empty sockets), should be easy enough to find some pictures or take some and post them so you can place them with the appropriate ones Edited September 2, 2019 by _The Doctor__ 1 Quote Link to comment Share on other sites More sharing options...
KLund1 Posted September 2, 2019 Author Share Posted September 2, 2019 All three have the same missing chips. I can make out some of the chip numbers from the flyer on Curt's site. but not all. If anyone has more info about what should go into the sockets please share. Thanks 1 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted September 2, 2019 Share Posted September 2, 2019 I just went to Curt's picture and you can zoom in and read the chips so that's cool. Right on down to the print grain. Nice. Thanks for the tip, I followed the quoted post to the link. Quote Link to comment Share on other sites More sharing options...
KLund1 Posted September 2, 2019 Author Share Posted September 2, 2019 I cant read the chip number for the chip under the 5 in the flyer. can you? Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted September 2, 2019 Share Posted September 2, 2019 7 hours ago, KLund1 said: All three have the same missing chips. I can make out some of the chip numbers from the flyer on Curt's site. but not all. If anyone has more info about what should go into the sockets please share. Can only guess... it look likes that only the parallel port parts are installed. The PIA on the card will be mirrored (it´s register) to the I/O area (maybe $D7xx or so), the 74LS245 is used for latching the 8 databits.. Curt´s pictures shows the MC1489 voltage converter for serial communications. The 24 pin chip is a MC6850 UART (for serial). Some more logic ships for address multiplexing. The only strange thing is the crystal. By default, twisted frequencies like 1.8432 MHz are used to get "clean" baudrates like 19200, 9600 bps... on the card is a 4 MHz crystall installed, with clock dividers (74LS74). More Re-Engineering needed ? 1 Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted September 2, 2019 Share Posted September 2, 2019 3 hours ago, KLund1 said: I cant read the chip number for the chip under the 5 in the flyer. can you? I would say it´s a MC1488 - the MC1489 counterpart is found at the most left place. 1 Quote Link to comment Share on other sites More sharing options...
+Stephen Posted September 2, 2019 Share Posted September 2, 2019 Awesome - never knew those existed! Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted September 2, 2019 Share Posted September 2, 2019 (edited) it tops out at 9600, but this can be improved. Edited September 2, 2019 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
KLund1 Posted September 30, 2021 Author Share Posted September 30, 2021 Hi all, Back to these cards again. I used the archive.org wayback machine to get to Curts site and pulled the flyer for this card hoping to be able to read the chip numbers. But the resolution seems low. I cant read the chip numbers I need to get to populate these cards. I can only read the 3 74LS151's at A5,6,7 positions. Can any of you out these see the numbers on the other chips I need? From above I see I need a MC6850 UART; a 74LS245 but can't see its position on the board; a MC1489 but can't see its position on the board; Thanks 1 Quote Link to comment Share on other sites More sharing options...
Faicuai Posted September 30, 2021 Share Posted September 30, 2021 12 minutes ago, KLund1 said: Back to these cards again Good-old Slot-3 strikes again... No 10i90, no PBI, etc. 8-) Only a small modification on (internal) shield-plate, attached underneath top cover (completely invisible), and voila! Easy-peasy and extraction of card-ribbons... Very nice, and super rare, indeed!! (FYI, scan is really hard to read...) Quote Link to comment Share on other sites More sharing options...
TGB1718 Posted September 30, 2021 Share Posted September 30, 2021 (edited) Should be easy to find the 1489 socket, if the UART is a 6850 as @tf_hh says, then using a meter from pin 2 of the UART must got to one of the 1489 pins, either pin 3, pin 6, pin 11 or pin 8 There's only 3 14 pin sockets to check Edited September 30, 2021 by TGB1718 1 Quote Link to comment Share on other sites More sharing options...
+hunmanik Posted October 1, 2021 Share Posted October 1, 2021 Higher rez here? CMC-Parallel-Serial-Card.pdf 1 Quote Link to comment Share on other sites More sharing options...
Faicuai Posted October 1, 2021 Share Posted October 1, 2021 57 minutes ago, hunmanik said: Higher rez here? CMC-Parallel-Serial-Card.pdf 8.4 MB · 5 downloads MUCH better !!! Quote Link to comment Share on other sites More sharing options...
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