ASCII Terminal

[BigBlueDad]

I am trying to get "Geoff's VT100 Terminal Kit" (https://www.tindie.com/products/petrohi ... minal-kit/) working with the Altair Clone. I can easily attach the keyboard and monitor, but am struggling to understand exactly how to get the Altair Clone to work with it. Specifically, I'm not sure exactly how the DB-25 to USB is accomplished. Has anyone used this terminal? Thanks.

[AltairClone]

I think the serial port connection is on the white connector with the Tx Rx signals. I’m not sure how the board differentiates between TTL and RS232 levels because it says it supports both. Hopefully you can contact the designer because the docs don’t seem to say anything about how to connect to the board.

Mike

[BigBlueDad]

Thank you. Yes, I was thinking the same thing. The RS232 levels are set through the software itself, which is configurable using the keyboard and monitor.

So my plan is to connect those Tx, Rx, and GND to the Altair Clone through a DB9 connector I wire up myself.

[toml_12953]

Thank you. Yes, I was thinking the same thing. The RS232 levels are set through the software itself, which is configurable using the keyboard and monitor.

So my plan is to connect those Tx, Rx, and GND to the Altair Clone through a DB9 connector I wire up myself.

That's the way to go, alright. You may have to reverse the RxD and TxD lines, though, connecting the AD's RxD to the terminal's TxD and the AD's TxD to the terminal's RxD. Experiment to see if it's necessary.

[BillO]

I'm working on a version of this with a female DB9 connector on it and a different layout to facilitate mounting to the back of, and powering from an LCD monitor.

When I get some time I'll document it over in the 8800c forum.

[BigBlueDad]

Just wanted to follow up and say that I got this working.

I provided my own power to the board, which meant removing the "USB Power" jumper and providing power directly to the power terminals.

I configured the board to accept RS232 signals using the configuration program built into the terminal

I connected a DB9 male to the board
-GND to GND
-Tx to Tx
-Rx to Rx

Then plugged in the Altair Clone DB25 to DB9 cable that came with it. Turned on the Altair Clone, and was able to use the keyboard and monitor.

Thanks to everyone for the help. I'm excited to be able to use the clone without having to connect it to a laptop.

[AltairClone]

Great progress!