I found this TL16C554 chip on AliExpress and decided to use it for a quad serial interface board.
The A channel are used to talk to a terminal program on the PC, like Tera Term or other.
The three other channels are free to use for other stuff.
A few weeks ago I decided to try to build a PC based "hard drive" for the 8080, using one serial port dedicated for that job. So I have made a small adjustment to the B port for that - not shown here.
XBUS Serial IO
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