bro...@pacific.net said: > UARTs are not mandatory, a simple transistor level shifting circuit is all > that's needed for TTL/RS-232 levels.
I think you are confusing UARTs with level shifters. In the old days, transistors were expensive enough that a 68000 class CPU was all that could fit on a chip. All memory and peripherals were off chip. While not quite mandatory, most of the time it made sense to use a UART chip. If you had a FPGA, you could put a simple UART in there. (But back then, FPGAs weren't very big either.) If the CPU was idle, you could bit-bang things. -- These are my opinions. I hate spam. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
