31 Jan
2025
31 Jan
'25
1:31 p.m.
On Fri, 31 Jan 2025, David Wade via cctalk wrote:
Lets look at some of the other pins:-
RTS/CTS - Request to send/clear to send - Hardware flow control.
DTR/DSR - Is comms up and running
RI - Ring Indicator - a call has arrived
TCK/RCK - Used for timing on synchronous links so BI-SYNC/SDLC/HDLC
LL/RL - enable loop back...
The first printers that I used on TRS80 were aSilent 700, and
later, a DTC300 (Hytype 1 printing terminal)
It took a while to figure out the cabling.
Interfacing printers to microcomputers was sometimes confusing.
Joe Capbells book "The RS232 Solution" was primarily about that.
There was even a case where a user handed over computer and printer to a
store to get an appropriate cable; after an excessive length of time, the
user shot and killed the store owner.
The first parallel printers might have been Centronics. Hence the
interface and blue ribbon connector being called "Centronics parallel"
The Epson MX-80 became one of the most popular; the FX-80 was an enhanced
descendent of it.
"serial" could be used to refer to only using one signal wire (plus a
groun).
But, it can also refer to whether the bits were sent one at a time, or in
parallel.