Force Computers PENT/CPCI-721, Installation Manual

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Controls, Indicators, and Connectors Front Panel
PENT/CPCI-721 3 - 5
Keys
The PENT/CPCI-721 provides front panel keys which will be described
below.
Reset Key
When enabled and toggled, it instantaneously affects the CPU board by
generating a reset. The reset generates a PCI reset and is programmable
to be globally or local to the CPU board via the PCI Bus Control Regis-
ter.
A reset of all on-board I/O devices and the CPU is performed when the
reset key is pushed to the active position. RESET is held active until the
key is back in the inactive position, however at least 200 ms are guaran-
teed by a local timer. Power fail (below approximately 4.7V) and power
up – both lasting at least 200 ms to 300 ms – also force a reset to start the
CPU board.
Abort Key
When enabled and toggled, it instantaneously affects the CPU board by
generating an interrupt request (NMI) via the PCI-to-ISA bridge. This
allows to implement an abort of the current program, to trigger a self-
test or to start a maintenance program.
Note: For information on how to disable the keys, see the “Action
Plan” section on page 2-10.