ModMon

The name ModMon stands for Modem Monitor. ModMon will show you a realtime display of your computer's modem status register for a given COM port. This means that as your modem's status changes, ModMon will reflect these changes in its table.

For each of the indicators in the display, ModMon will display a "ú" (light bullet) to signify "off" or "low", and a "Û" to signify "on" or "high". To make ModMon display your modem's status register on a specific COM port, type ModMon #, where # is the COM port number. If you add the /b switch, ModMon will beep as your phone line rings. If a COM port you specify is not installed, you will not see a ú or a Û in the table. For example, if you type MODMON 3, and you don't have a device on COM 3, the table will remain blank.

Example: If you have a modem on COM 2, and would like to monitor its activity and hear the telephone ring through your PC speaker you would type: ModMon 2 /B

Here is a list of the indicator names and their descriptions:

CCT: Change in "clear to send" CDS: Change in "data set ready" CRI: Change in "ring indicator" CDC: Change in "data carrier detect" CTS: "Clear to send" set high DSR: "Data set ready" set high RNG: "Ring indicator" set high DCD: "Data carrier detect" set high

Here is a further explanation of the quoted terms above.

Clear to send: The modem is ready to receive characters from the PC. Data set ready: The modem is powered on and ready to operate. Ring indicator: The phone line is ringing. As the line rings, RI is held high (on) so that your PC can detect the rings. Data carrier detect: The modem is connected to another modem.