Here's a list of commands, as best as I can remember without digging out the docs (which are at home).

• ATDT<phone number> will dial the phone number. The modem will attempt to negotiate with the far-end answering device.
• ATDT<phone number>; will dial the number will dial the number and return to command state. At this point, no negotiation will be attempted. You can either wait programatically a given amount of time, or, add commas to the end of the phone number. Each comma will provide aproximately 2 seconds of delay. You can use other dial modifiers here, such as 'W' to wait for a secondary dial tone (PBX systems), '!' to flash the switchhook, and a few others.
• If you wish to send additional touch tones after the far end has answered (but not negotiated), you can use 'ATDT<numbers>;'.
• ATO - This will go 'online'. I can't remember if this will negotiate a connection or not if an existing connection is not present. I think it will.
• ATH - This will hang up the modem. ATH0 is the default, which hangs it up. ATH1 will take the modem off hook, without dialing.
• ATR - Renegotiate, and resume connection.
• ATE - 0 will turn command echo off (desirable in a script), 1 will enable command echo (better in a terminal program)
• ATV - 0 will turn off verbose result codes (numbers as responses), 1 will enable (text strings as a responses). ATV0 is common for scripts, ATV1 for terminal programs.
• ATX - Extended result codes. There are a handful of different values, but ATX4 is most commonly used.
• ATZ - Reset the modem (handy after you've dorked all the settings up.
• A/ - Repeat last command. Handy when dialing and the number is busy.

Any character sent to the modem while it is dialing or negotiating will result in the connection being dropped and the modem going on-hook. Commands can be terminated by a CR, or LF, but not both.

I'm doing this from memory. I have the complete specs at home (somewhere) from when I worked at Hayes. If you need more details, feel free to contact me at the e-mail address below.

--Chris

e-mail jcwren