Black Box ServSwitch SW721AE-R2, User Manual

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“R2” SERVSWITCH
4.3.9 R
ESET
This command, along with the two commands described in the next two sections,
comes in handy when certain problems arise. It will reset or refresh your shared
equipment. Issue it if (a) your shared keyboard gets stuck or begins behaving
oddly, (b) you need to send mouse data to a CPU that hasn’t enabled the mouse
(this can happen if you boot up the CPU while the ServSwitch is off or
disconnected), (c) your video display has not been updated to show current
conditions, or (d) while using a PS/2 type mouse, you unplug it, then plug it back
in. To issue the Reset command, press and release the left Control Key, then type
[R].
If you’re using a PS/2 type mouse, don’t issue this command to a CPU that doesn’t
have a mouse driver loaded. Many CPUs will crash if you send them unexpected
mouse data.
4.3.10 S
END
N
ULL
B
YTE
PS/2 type mice send control data to CPUs in three-byte increments. Sometimes,
because of electronic transients, unusual power-up effects, or plugging and
unplugging of cables from live equipment, the currently selected CPU in a
ServSwitch system can lose one or two bytes of this control information and get
“out of sync” with the shared mouse. In this situation, the mouse might seem to
refuse to move the pointer or cursor, open windows for no reason, or exhibit other
strange behavior. To get the CPU back in sync, send this command to tell the
ServSwitch to send a “null byte” to the CPU’s PS/2 mouse port (this has no other
effect than getting the CPU “caught up”). To issue the Send Null Byte command,
press and release the left Control Key, then type [N]. If the mouse still isn’t right
after you issue this command, the CPU must have been two bytes out of sync.
Issuing the command again should do the trick. The CPU will be thrown out of
sync if it uses a PS/2 mouse and it’s in sync when you issue this command. Issue
this command two more times to get it back in sync again. This command has no
effect on CPUs that are not attached to your ServSwitch system through a PS/2
mouse port. If you have version 9.01 or higher of the Microsoft mouse driver, the
CPU should never get out of sync. Contact Microsoft if you would like to upgrade
your Microsoft mouse driver.