Anyone with a classic Macintosh ever have issues converting RS422 to RS232 and having Tx work but not Rx?
I have a Macintosh 512ke connected to a DTech RS422 converter [1] using the Macintosh RS422 pinout [2].
The female side of the Dtech is connected to a Prolific Technology, Inc. PL2303 Serial Port plugged into a RaspberryPi 3 with agetty connecting to /dev/ttyUSB0.
The RPI is running Raspbian 12 and setup to use the USB Serial with `/sbin/agetty 9600 - vt220` and I am able to see logins via journalctl.
I've tried MacTerminal and Zterm on the Macintosh, all set to 9600 baud, Databits 8, Parity None, Stop Bits 1, flow control and hardware handshake off. I've tried various combinations of these with the same results.
Connecting a multi-meter to the RPI serial and a tail -f of continual output, there is voltage change, verifying the RPI serial terminal is sending data, but isn't received by the Macintosh.
The attached screenshot shows Zterm sending commands successfully to the RPi and then the shell history of the fatmac user, verifying Tx from the Macintosh is working.
Any ideas on why the Macintosh is not receiving data from the RaspberryPi but is able to transmit?
#vintagemac #retrocomputing #raspberrypi #macintoshclassic #macintosh128k #macintosh #linux1.
https://www.amazon.com/dp/B0196AO1IG2.
https://allpinouts.org/pinouts/connectors/serial/apple-macintosh-serial-9-pin/