CentOS 5 (Red Hat-based). I’m connecting to a Cisco Router via serial cable.

1) run ‘minicom -s’ first, to enter configuration mode, you’ll open a text-based menu. Note: Use «ENTER» to exit any menus except the main menu.

2) Under «Serial Port Setup» mine was set to default /dev/modem and 38400. I had to manually change it to 9600 and set the device to /dev/ttyS0. Remember to hit ENTER to exit, do NOT try to use «Q» to «Quit», if you’re under the speed/parity selection window that’ll change your parity to 2 (this is where I learned that, heh).

3) Go under «Modem and Dialing» and remove the «Init String». Anything in this field will be sent to the device when you connect. The default AT string won’t bother a Cisco device as far as I know, especially if it’s not in enabled or in config mode when you connect, but it’s kinda annoying to have it pop up on connect.

4) From the main menu use «Save setup to DFL» to create a new config file for minicom.

Damos permisos de ejecución

Buscamos donde esta minicom con:
# which minicom
/usr/bin/minicom

Miramos sus permisos de minicom con:
# ls -la /usr/bin/minicom
Salen q permiten al grupo uucp

Editamos /etc/group y ponemos al usuario juanito en el grupo uucp

Miramos sus permisos de /dev/ttyS0:
# ls -la /dev/ttyS0
Salen q permiten al grupo tty

Editamos /etc/group y ponemos al usuario juanito en el grupo tty

Damos permisos de lectura y escritura a /dev/ttys0 con:
# chmod 666 /dev/ttys0