Model T Serial Cable: Difference between revisions

From Tandy Tech
Jump to navigation Jump to search
No edit summary
No edit summary
Line 27: Line 27:
:DCD<-->RTS / DSR+CTS<-->DTS
:DCD<-->RTS / DSR+CTS<-->DTS
:WTF??? HP are monsters.
:WTF??? HP are monsters.
Pending Verification:
*[https://www.tripplite.com/null-modem-serial-db9-serial-cable-db9-db25-female-male-6-ft~P456006/ Tripp-Lite P456-006]
*[https://www.tripplite.com/null-modem-serial-db9-serial-cable-db9-db25-female-male-6-ft~P456006/ Tripp-Lite P456-006]
:Same as Monoprice 479
*[https://www.amazon.com/dp/B005KCPOHM Epson CEPS-003BLK]
*[https://www.amazon.com/dp/B005KCPOHM Epson CEPS-003BLK]
:DTR<-->DCD+RTS+CTS

Revision as of 02:34, 31 October 2017

The ideal cable to go from a PC to a Model 100, 102, 200, or 600, is "9F/25M serial null-modem full-handshake".

The serial ports on Models 100-600 are wired DTE, the same as a com port on a PC, but with a female connector, unlike any pc.

This is a backwards configuration from everything else today. There is some suggestion that maybe this is actually the original standard, and IBM came along later and changed it by putting male connectors on their PCs, but in any event, 25pin DTE ports being male has been the universal standard now for decades.

  • Any modem or printer or digital scale or any other kind of peripheral with a serial connection will be wired DCE with a female connector, usually 25 pin.
  • Any serial port card or usb serial adapter for a PC will be wired DTE with a male connector, usually 9 pin.

That means that usually you always need some kind of adapter between a PC and a M100/102/200/600.

The easiest way to connect with parts you are most likely to already have lying around, is to use a 9F/25M Modem Cable combined with a 9M/F Null-Modem Adapter.

Ideal, all-in-one cables:

Slightly less ideal cables. All-in-one, but not full-handshaking, good for software flow control only:

These cables work fine for TPDD client/server connection, and almost everything else, since there isn't even any way to *set* hardware flow control in either BASIC or TELCOM anyway.
But the hardware in the M100 *can* actually do RTS/CTS, if you manipulate the UART registers yourself from a machine language program. The only software I know of that does this is HTERM. So these cables are NOT suitable for HTERM
Shorts RTS/CTS to self-satisfy, but curiously, actually passes DTR/DSR correctly
Same as Monoprice 479
This "HP PLotter" cable is bizarre.
DCD<-->RTS / DSR+CTS<-->DTS
WTF??? HP are monsters.
Same as Monoprice 479
DTR<-->DCD+RTS+CTS