Xycom XVME-653, Manual

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XVME-653/658 Manual
2-4
Switch Settings
The XVME-653/658 has one four-pole switch (SW1). This switch controls the system
response to the front panel Reset switch (SW2). Table 2-7 shows the switch settings re-
quired to reset on the XVME-653/658 CPU, to reset only the VME backplane, or to reset
both. The switch 3 is reserved and should always be closed. The XVME-653/658 is
shipped with all four switches in the closed position (which causes SW2 to reset both the
XVME-653/658 and the VME backplane). Both switches are shown on Figure 2-1.
Table 2-7 Four-Pole Switch (SW1) Settings
For the front panel reset
switch (SW2) is to do this:
The four-pole switch
(SW1) settings must be:
1 2 4
No Resets Closed Open Open
Reset the VME backplane only* Open Closed Open
Reset the XVME-653/658 CPU only** Closed Open Closed
Reset both the VME backplane and the
XVME-653/658 CPU (default setting) Closed
√√√√
Closed
√√√√
Closed
√√√√
*Caution
Resetting only the VME backplane will reset the Universe chip.
**Caution
If you have an older XVME-653 which has a Tundra Universe chip in-
stead of a Tundra Universe II chip (U19), you do not have the ability to
reset the CPU only. The option to reset both the CPU and the VME
backplane still works normally.
You can tell a Universe from a Universe II by looking at the model num-
ber on the top of the chip. The Universe has CA91C042-33CE and the
Universe II has CA91C142-33CE.