Technical information

1.3 Power-Up
At power-up, the console program determines the console device type and
console language, then runs the self-tests for the CPU and memory. You
choose the console language when you perform the set-up operations during
your console terminal installation procedure.
You determine the type of power-up mode by setting the Power-Up Mode
switch on the CPU cover panel. See your VAX 4000 Model 200 Operation
manual for the following power-up information:
• Power-up procedures
• Power-Up Mode and Break Enable/Disable switch settings
• Examples of successful power-up sequences
• Boot and autoboot procedures
See the VAX 4000 Model 200 Troubleshooting and Diagnostics manual for
examples of problems you may encounter during power-up.
1.4 Console I/O Mode Overview
If you set the Break Enable/Disable switch on the CPU cover panel to
enable, the console program enters Console I/O mode after the power-
up self-tests are completed successfully. The console program also enters
Console I/O mode in response to any external halt condition.
CAUTION: Do not press the Restart button while the console program is
in console mode. Doing so destroys the system state and prevents normal
operation.
Console I/O mode allows you to control the system by entering commands at
the console prompt >>>. You may enter these commands in either uppercase
or lowercase letters. Enter each command, then press
Return
.
1.4.1 Control Characters in Console I/O Mode
Table 1–1 lists the keypad control characters that have special meaning in
Console I/O mode.
1–4 VAX 4000 Model 200 Technical Information