Raven-Detected Errors; Timers; Interrupt Delivery Modes - Motorola MVME2600 Series Reference Manual

Raven-Detected Errors

Raven-detected errors are grouped together and sent to the interrupt logic
as a singular interrupt source. The interrupt delivery mode for this interrupt
is distributed. The Raven Error Vector-Priority Register should be
programed for high true level sensitive activation.
For system implementations where the RavenMPIC controller is not used,
the Raven-Detected Error condition will be made available by a signal
which is external to the Raven ASIC. Presumably this signal would be
connected to an externally sourced interrupt input of a MPIC controller in
a different device. Since the MPIC specification defines external I/O
interrupts to operate in the distributed mode, the delivery mode of this
error interrupt should be consistent.

Timers

There is a divide by eight pre-scaler which is synchronized to the Raven
clock (MPC processor clock). The output of the prescaler enables the
decrement of the four timers. The timers may be used for system timing or
to generate periodic interrupts. Each timer has four registers which are
used for configuration and control. They are:
Current Count Register
Base Count Register
Vector-Priority Register
Destination Register

Interrupt Delivery Modes

The direct and distributed interrupt delivery modes are supported. Note
that the direct deliver mode has sub modes of multicast or non-multicast.
The Interprocessor Interrupts (IPIs) and Timer interrupts operate in the
direct delivery mode. The externally sourced or I/O interrupts operate in
the distributed mode.
In the direct delivery mode, the interrupt is directed to one or both
processors. If it is directed to two processors (i.e. multicast), it will be
delivered to two processors. The interrupt is delivered to the processor
Raven Interrupt Controller Implementation
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