Some other Notes! Use ATS0=2 C/R (Number of rings for modem to answer = 2) (I've found that a minimum number of 2 rings is best!) Use ATM0 C/R (Speaker on modem = OFF & ATM1 = Speaker on until connected)
Before you disconnect the line connection, Make sure that you are back into the Meridian SL1 program!. Also key "+++" first & wait until you get the "OK" prompt. (It takes you back to the modem!) If you don't do this, then the TTY port can disable it's self or the modem will lock up.
How to configure the US Robotics 56K external Modem via a RS232 lead into your P.C.
Key in the following à
ôAT&A3&B0&C1&D0&H1&I0&K0&M4&N6&R1&S0&T5&U0&Y1ö C/R. The modem will answer with ôOKö Followed by ôATB0E1F1L2M0Q1V1X4Y0ö C/R. Enter the ôSö Registers as shown in bold above. i.e.. ôATS0=2ö C/R.
Finally enter ôAT&W0ö C/R to store the data into memory. Power Modem "OFF" & "ON". The prompt ôATI4ö C/R will list out the values stored in memory.
To connect the Modem at 14400 baud rate & Meridian 1 TTY port at 19200 baud rate, Then use the settings ôAT&N8ö C/R followed by ôAT&W0ö C/R & power off & on the Modem again.