User's Manual

PMAC VME Hardware Reference Manual
16 PMAC VME CPU Boards
Legacy PMAC VME Standard CPU Board (602398, 602271)
This table shows the jumper settings for the standard PMAC CPU boards with batteries. These boards are
used when the PMAC is ordered without any memory or CPU options, or with Option 5 (not 4A, 5A, or 5B).
E Point and
Physical Layout
Description Default
E1
Jump pin 1 to 2 to disable watchdog timer (for test purposes
only).
Remove jumper to enable watchdog timer.
Note: On old CPU boards with white CPU IC, E1 function
is opposite.
No jumper installed
E2
Jump pin 1 to 2 to boot from host port.
Remove jumper to boot from IC.
No jumper installed
E3
Jump pin 1 to 2 to use BAT1 battery (shorts BAT2 positive
terminal to GND).
Jump pin 2 to 3 to use BAT2 battery (shorts BAT1 positive
terminal to GND).
Remove jumper to use both batteries.
2-3 jumper installed (20
MHz)
No jumper installed (30
MHz).
Legacy PMAC VME Option CPU Board
This table shows the jumper setting for the option PMAC CPU boards with flash memory
backup (no battery). These boards are used only when the PMAC is ordered with Option 4A,
5A, or 5B (not standard or Option 5).
E Point and
Physical Layout
Description Default
E1
Jump pin 1 to 2 to disable watchdog timer (for test purposes
only).
Remove jumper to enable watchdog
timer.
No jumper installed
E2
Remove jumper for use on first generation PMAC.
Jump pin 1 to 2 for use on second generation PMAC
(PMAC2).
No jumper installed *
E3
Remove jumper for use on first generation PMAC.
Jump pin 1 to 2 for use on second generation PMAC
(PMAC2).
No jumper installed *
* Pins for jumpers E2 and E3 may not be installed on Option CPU boards for 1st generation PMACs.