Any rs232 pinout diagram. The only special thing about the m100 is that the 25pin plug is DTE (like any other computer, vs a modem or other peripheral) and female instead of male, and so the 25pin plug on the cable must be male, and so you just have to go by pin numbers and signal names, not physical location, when you look at diagrams.
IE: to connect to a PC, both the pc and the m100 are DTE. So you pull up any rs232 pinout diagram for 9-pin DTE and 25-pin DTE. Connect the signal names, and then use the pin numbers to know which actual pins to use on each end if you're building your own cable by hand. RTS on one end goes to CTS on the other end. The pin # for CTS on the 25pin is the same pin# whether it's male or female, but if you're looking at a drawing of the physical location of the pin, the male and female locations are mirror images, so don't look at layout diagrams just pin numbers and signal names. But don't build a cable by hand. There are pre-made made cables that are fully correct null-modem, factory molded, with the right connectors already on both ends to connect a M100 to either a PC with built-in com port or a usb-serial adapter. Here are 3 such, along with a couple usb-serial adapters which are slightly more ideal than most, simply because they are FTDI chip and have nuts instead of screws. http://tandy.wiki/Model_100_102_200_600_Serial_Cable I recommend the C2G cable and the Sabrent usb adapter for an ideal setup. On Wed, Jan 10, 2018 at 6:48 PM, Peter Vollan <[email protected]> wrote: > Where can I find a diagram of the correct null modem connection for > the Model 100? I may make one myself to be sure to get it right. > -- bkw
