31 Jan
2025
31 Jan
'25
7:02 p.m.
On Jan 31, 2025, at 1:55 PM, Steve Lewis via cctalk
<cctalk(a)classiccmp.org> wrote:
re: on UARTS..
Didn't it basically standardize the process of that task of converting a
byte to bits and vice versa, in a fashion specified by RS232?
No, RS232 is a way to send binary information between devices, using specified voltage
levels and interface conventions. It has nothing to with UARTs.
And do so at the above-300-baud rates, since that task
was too stressful
for 1MHz processors to pull off on its own (in addition to whatever else it
was doing, like flashing a cursor on a CRT?)?
And the buffer just gave grace time for if one of the systems got overly
busy? (like when scrolling said CRT)?
You can do a UART in software at pretty high speeds if the processor doesn't have too
much else to do. Conversely, a 110 baud UART is very painful in software on a 4004.
Might a UART be an early example of an ASIC?
Yes, I would say so.
paul