Pci Bus 0.0 Speed Switch (S4-1); Vme Scon Select Header (J27); S4-1 Settings; J27 Settings - Emerson MVME55006E Installation And Use Manual

1.7.8

PCI Bus 0.0 Speed Switch (S4-1)

This switch can force PCI bus 0.0 to run at 33 MHz rather than the standard method of allowing
the PMC board to control whether the bus runs at 33 MHz or 66 MHz. Set to 1, it allows the PMC
board to choose the PCI 0.0 bus speed. Set to ON forces PCI bus 0.0 to run at 33 MHz.
Figure 1-10
1
2
PMC board controls
PCI 0.0 bus speed
(factory configuration)
1.7.9

VME SCON Select Header (J27)

A 3-pin planar header allows the choice for auto/enable/disable SCON VME configuration. A
jumper installed across pins 1-2 configures for SCON disabled. A jumper installed across pins 2-
3 configures for auto SCON. No jumper installed configures for SCON always enabled.
Figure 1-11
J27
1
2
3
Always SCON
MVME55006E Single Board Computer Installation and Use (6806800A37H)

S4-1 Settings

S4-1
1
ON
2
Force PCI bus 0.0
to run at 33 MHz

J27 Settings

J27
1
2
3
No SCON
Hardware Preparation and Installation
ON
J27
1
2
3
Auto-SCON
(factory configuration)
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