Using the vt220 Terminal Emulator

Recent MicroCode Levels allow the use of an integrated vt220 terminal emulator in addition to the standard line mode terminal. The vt220 terminal is connected to /dev/ttyS1. The line mode terminal is connected to /dev/ttyS0. If the vt220 emulation is available, an icon for an integrated vt220 ASCII console appears next to the icon for the 3215 console on the HMC/SE.

To activate vt220 support on your machine, edit /etc/inittab as user root. Look for the following line and delete the leading # sign:

#2:2345:respawn:/sbin/mingetty --noclear /dev/ttyS1 xterm

Save the file and run telinit q to pass the changes in /etc/inittab to init. The vt220 terminal should then be ready to use. If not, try hitting Enter at the terminal until the login prompt appears.

Make sure that you do not apply the changes as described above to a system that does not support vt220 terminal emulators. Otherwise, login might become impossible on this system and you will be shown the following message:

INIT respawning too fast, disabled for 5 minutes.

To redirect the kernel messages at boot time from the system console to the vt220 terminal, add the following entries to the parameters line in /etc/zipl.conf:

console=ttyS0 console=ttyS1

The resulting parameters line would look like the following example:

parameters = "root=/dev/dasda2 TERM=dumb console=ttyS0 console=ttyS1"

Save the changes in /etc/zipl.conf, run zipl, and reboot the system.