Model T Serial Cable: Difference between revisions

From Tandy Tech
Jump to navigation Jump to search
No edit summary
No edit summary
Line 1: Line 1:
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 ideal cable to go from a PC to a Model 100, 102, 200, or 600, is "9F/25M serial null-modem full-handshake".
That's an uncommon configuration to find pre-molded in a single cable, but one way to find them is to search for "HP Plotter Cable" or "Serial Printer Cable".


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.
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.
Line 14: Line 12:


Ideal, all-in-one cables:
Ideal, all-in-one cables:
*[https://www.cdw.com/shop/products/C2G-null-modem-cable-6-ft-white/1153481.aspx C2G 03019] (fake DCD from DSR/DTR)
*[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]
*[https://www.cablesondemand.com/category/CSNULL/product/CS-DSNL4259MF/URvars/Items/Library/InfoManage/CS-DSNL4259MF.htm Amphenol CS-DSNL4259MF-005]
*[https://www.cablesondemand.com/category/CSNULL/product/CS-DSNL4259MF/URvars/Items/Library/InfoManage/CS-DSNL4259MF.htm Amphenol CS-DSNL4259MF-005]
*[https://www.cablewholesale.com/products/serial-modem-cable/hp-plotter-cables/product-10d1-13306.php CableWholesale 10D1-13306]
*[https://www.startech.com/Cables/Serial-Parallel-PS-2/DB9-DB25/10-ft-Cross-Wired-DB9-DB25-Serial-Null-Modem-Cable~SCNM925FM StarTech SCNM925FM] (no DCD)
*[https://www.startech.com/Cables/Serial-Parallel-PS-2/DB9-DB25/10-ft-Cross-Wired-DB9-DB25-Serial-Null-Modem-Cable~SCNM925FM StarTech SCNM925FM]
*[https://www.amazon.com/dp/B005KCPOHM Epson CEPS-003BLK]
*[https://www.amazon.com/dp/B005KCPOHM Epson CEPS-003BLK]


Slightly less ideal cables. All-in-one, but not full-handshaking:
Slightly less ideal cables. All-in-one, but not full-handshaking, good for software flow control only:
:These cables works 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
*[https://www.monoprice.com/product?p_id=479 Monoprice 479]
*[https://www.monoprice.com/product?p_id=479 Monoprice 479]
:Shorts RTS/CTS to self-satisfy on both ends. (but curiously, actually passes DTR/DSR correctly)
:Shorts RTS/CTS to self-satisfy on both ends. (but curiously, actually passes DTR/DSR correctly)
:Works 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 this cable is NOT suitable for HTERM.
*[https://www.cablewholesale.com/products/serial-modem-cable/null-modem-cables/product-10d1-21303.php CableWholesale 10D1-2103]
*[https://www.cablewholesale.com/products/serial-modem-cable/null-modem-cables/product-10d1-21303.php CableWholesale 10D1-2103]
:Same as Monoprice 479
:Same as Monoprice 479
 
*[https://www.cablewholesale.com/products/serial-modem-cable/hp-plotter-cables/product-10d1-13306.php CableWholesale 10D1-13306]
Suspect, awaiting verification:
:This "HP PLotter" cable is bizarre.
*[https://www.cdw.com/shop/products/C2G-null-modem-cable-6-ft-white/1153481.aspx C2G 03019]
:DCD<-->RTS / DSR+CTS<-->DTS
:WTF??? HP are monsters.

Revision as of 22:05, 28 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, 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 works 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 on both ends. (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.