Sending AT commands with the cu command

If you have the Basic Network Utilities (BNU) installed, use the cu command to configure a modem as follows.

The commands and settings discussed in this section configure a Hayes-compatible modem with the basic parameters needed for operation on the server's serial ports.

Add the following line to your /usr/lib/uucp/Devices file. Do not add the line if it is already in the file. (Replace # with the number for your port.)
```
Direct tty# - Any direct
```
Verify that the tty is disabled by typing the following:
```
pdisable tty#
```
Type the following command:
```
cu -ml tty#
```
You should see a message that says Connected.
Verify that you have the attention of the modem by typing the following:
```
AT
```
The modem should respond with OK. If it didn't, refer to Modem troubleshooting.
For additional AT commands and their descriptions, see AT commands.
Depending on which getty option you selected, enter one of the following commands. Substitute the tty device for n.
- penable ttyn
- pshare ttyn
- pdelay ttyn
- pdisplay ttyn

The modem is now configured with the basic commands needed to perform most of the operating system's serial communications needs. If you have problems, invoke the cu -dl command to start a diagnostic trace on the connection.