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Moonferret
November 26th, 2017, 07:25 AM
Hi Folks!

I'm in the process of getting my Altair 8800 up and running. The machine has a pair of 88-SIO cards installed. A type A (RS232) and a type C (20ma TTY). I'm a little unsure how I go about wiring these up to a 25pin port on the rear of the machine. The Tx & Rx on the RS232 board is straightforward but do I need the handshaking?

Anybody have wiring diagrams for these boards?

Cheers,
Dave

deramp5113
November 27th, 2017, 03:45 PM
Here are several docs related to the SIO. Verify yours has been updated to the Rev 1 flavor. Most all have.

http://deramp.com/downloads/index.php?dir=altair%2Fhardware%2Fsio_serial_inter face%2F

Mike

Moonferret
November 29th, 2017, 01:18 PM
Thanks for the link Mike. The boards had already been updated to Rev.1 and I've managed to create the cables from the information in those PDFs. Unfortunately, a tantalum cap on one of the memory boards has gone pop and seems to have taken out part of the front panel. Run doesn't seem to work although single step and the other functions do. I think this is going to be a job for the weekend when I've got a few hours spare :(

Cheers,
Dave

deramp5113
February 7th, 2018, 06:52 PM
Here are several docs related to the SIO. Verify yours has been updated to the Rev 1 flavor. Most all have.

http://deramp.com/downloads/index.php?dir=altair%2Fhardware%2Fsio_serial_inter face%2F

Mike

Here is a corrected link to the SIO documents: http://deramp.com/downloads/altair/hardware/sio_serial_interface/

Mike