remember the floppy disk 💾

When using the TRS-80 Model 100 with The Old Net Serial Wifi Modem, set the terminal to 300 baud, 8 Bits, No Parity, 1 Stop Bit, and Software Flow Control.

"Software Flow Control" is sometimes called "XON/XOFF flow control", in contrast to "hardware flow control" like RTS/CTS and DTR/DSR.

On the TRS-80 M100, select TELCOM. For RS-232C communications, the configuration description consists of a five character string of the format rwpbs, where:

• r Baud Rate. This is a number from 1 to 9, where 1 = 75; 2 = 110 ; 3 = 300 ; 4 = 600 ; 5 = 1200 ; 6 = 2400 ; 7 = 4800 ; 8 = 9600 ; 9 = 19200. M may be used. M sets built-in modem to 300 baud.
• w Word Length. This is a number from 6 to 8, where 6 = 6 bits; 7 = 7 bits; 8 = 8 bits.
• p Parity. Either E,O,N, or I where E = Even ; O = Odd ; N = None; I= Ignore.
• b Stop Bits. Either 1 or 2, where 1 = 1 stop bit; 2 = 2 stop bits.
• s XON/XOFF Status. Either E or D, where E = Enable; D = Disable.

To set up for use the wifi modem:

stat M8N1E

And then hit (Term - F4) Puts TELCOM into the Terminal Mode. And then you can do your AT commands.

Note: On the wifi modem the baud rate is set to 600 baud perhaps: Hold the Flash button down on the modem for 5 seconds and it will reset to 300 baud (one time). 

References: 

The TRS-80 Model 100 Quick Reference Guide
Old Net Wifi Modem Manual

First post. I think this title makes sense.

Here's a photo of a Laser 128/EX I have: