TC1796
System Units (Vol. 1 of 2)
Peripheral Control Processor (PCP)
User’s Manual
11-5
V2.0, 2007-07
PCP, V2.0
access. If an FPI Bus master performs an atomic read-modify-write access to a PCP
memory block, any concurrent PCP access to that block is stalled for the duration of the
atomic operation.
11.2.5
PCP Interrupt Control Unit and Service Request Nodes
The PCP is activated in response to an interrupt request programmed for PCP service
in one of the Service Request Nodes (SRNs) of the system (nodes associated with a
peripheral, the CPU, external interrupts, etc.). The PCP Interrupt Control Unit (PICU)
determines the request with the currently highest priority and routes the request together
with its priority number to the PCP Processor Core. It also acknowledges the requesting
source when the PCP starts the service of this interrupt.
The PCP itself can generate service requests to either the CPU or itself through a
number of PCP Service Request Nodes (PSRNs). The PSRNs are also used to store all
information required by the PCP Processor Core to allow the later restart of a channel
program when it is suspended in favour of a higher-priority service request. Please refer
to
for more detailed information on the operation of these nodes.