Black Box ServManager SW995A-R2, Руководство пользователя

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CHAPTER 4: Operation
4.3.6.A Keyboard Modes
Keyboard “modes” are electrical signaling protocols that determine how a
powered CPU and keyboard interact. A CPU and keyboard must use the same
mode in order to work with each other. Of the three standard keyboard
modes currently in use by IBM type computers, mode number 2 is the one
used by the vast majority of CPUs. It is also the default state of all 101-key and
PS/2 keyboards. Mode 1 is used primarily by certain PS/2 CPUs. Mode 3 is
used by RS/6000
® CPUs, some other UNIX ® based computers, and certain
specialized servers.
The ServManager supports all three of these modes: As it receives signals
from the keyboard, it sends them to the currently selected CPU by emulating
a keyboard of the appropriate mode for that CPU; as it receives signals for the
keyboard from the currently selected or scanned CPU, it sends them to the
keyboard by emulating a CPU of the appropriate mode.
Most CPUs that use keyboard mode 1 or 3 send a “mode command” to the
keyboard at power-up, to put the keyboard in the proper mode. ServManagers
and submaster ServSwitches can use these commands to automatically detect
each such CPU’s keyboard mode when you turn on the CPU
after it has been
cabled to the ServManager. However, ServManagers don’t automatically save
this value; unless you send them a Keep Settings command, they will forget
the modes they have detected when they are turned OFF, then default to each
port’s most recently saved setting when they’re turned ON again.
The ServManager can’t detect the CPU’s keyboard mode if your CPU
doesn’t send “mode commands” (most CPUs that use mode 2 fall into this
category) or if the CPU is already ON when you connect it to the
ServManager (it shouldn’t be). In these situations, the ServManager tries to
use the keyboard-mode setting stored in its nonvolatile memory for that port.
The factory default is mode 2 for all ports. Send the Set Keyboard Mode
command to change the keyboard mode for a port if:
• the CPU on that port uses mode 1 or 3,
• it uses mode 2, but the default setting of the port you want to connect it
to has been changed, or
• you don’t know which mode the CPU uses or the port is set for, but the
keyboard’s behavior makes you suspect that the port’s setting is wrong.