Modem type commands

Mpd 3.18 User Manual : Device Types : Modem type commands
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## 5.1. Modem type commands

This chapter describes commands that are specific to modem type links. These commands apply to the currently active link, and are only valid if the currently active link has type modem.

`set modem device devname`

  Modem links operate over serial ports. This command tells mpd which serial port to use for this link, and is required. The `devname` should be the pathname of a serial device, e.g., `/dev/cuaa0`.

`set modem var $variable string`

  Pre-sets the chat script variable `$variable` to contain the string `string`. See the chapter on chat scripting for more information on chat variables.

`set modem speed speed`

  This commands sets the initial serial port speed when opening the serial device, e.g., 9600, 57600, 115200. Note that you can always change the serial port speed later from within the chat script.

`set modem script connect-script`

  This command tells mpd which chat script to run in order to initiate a PPP connection for this link. The `connect-script` should correspond to a label in `mpd.script`. Mpd will jump to this label after opening the serial port device. If `connect-script` is not set, then the chat phase of the connection is skipped (e.g., if you have a direct null modem connection).

`set modem idle-script idle-script`

  This command tells mpd what to do with the serial port when the link is not connected. If no `idle-script` is set, then mpd will leave the serial port closed when not connected. Otherwise, when the link is disconnected mpd runs the `idle-script` chat script. If this script returns `failure`, then mpd restarts the script.

  Otherwise, (i.e., if it returns `success`) mpd examines the contents of the `$IdleResult` chat variable to decide what to do next. If it equals `answer` then mpd will assume that an incoming call has been answered and immediately enter PPP negotiation. If it equals `ringback` then mpd will close the serial port, reopen it, and initiate an outgoing connection normally (i.e., using `connect-script`).

  If `$IdleResult` contains anything else or is not set, then mpd acts as if `failure` had occurred and simply restarts the script.

`set modem watch +/-signal ...`

  Mpd normally tracks the carrier detect signal on the serial port and drops the connection when this signal is lost. You can disable this behavior with `set modem watch -cd`. Also, mpd can do the same thing with the DSR signal, though the default is to ignore DSR. To enable watching of the DSR signal, use `set modem watch +dsr`.

Mpd 3.18 User Manual : Device Types : Modem type commands
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