HP Vectra Reference Manual page 62

FOC Jumper Configurations
E7 E8
B
Figure 12
P2 P1
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The jumper EE, EC, ED is used to select or deselect the flexible disc
controller subsystem on the processor board. Placing a shunt
between EE and EC enables the flexible disc subsystem (operation
state-default). Placing a shunt between EC and ED disables the
flexible disc subsystem.
Processor Board 45