NonStop S-Series Server Description Manual (G06.24+)

Introduction
HP NonStop S-Series Server Description Manual—520331-003
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Components of Processor Multifunction (PMF) CRU
Components of Processor Multifunction (PMF) CRU
The processor multifunction unit (PMF) CRU consists of two boards and (for
NonStop S7000 servers) a power supply. The two boards are the processor and
memory board (PMB) and the multifunction I/O board (MFIOB). PMF CRUs in
NonStop S70000 servers and higher also have a power board.
An approximate representation of the PMF CRU is shown in Figure 1-4. The PMF CRU
is the type of CRU that is installed in slot 50 and 55 when the enclosure is configured
as a processor enclosure, as mentioned in the preceding topic.
The multifunction I/O board has six main logic elements, as indicated in the figure. The
ServerNet router and the ServerNet bus interface (SBI) provide the communication
paths into and out of the PMF CRU, both for input/output and for interprocessor
communication.
On the MFIOB are four ServerNet addressable controllers (SACs). The first of these
provides ServerNet addressability for the Ethernet port and for the service processor
(SP). The service processor has interfaces to both the ServerNet hardware and a
separate serial maintenance bus (SMB).
The other three SACs on the MFIOB are SCSI interfaces. Two of these connect to the
two separate internal SCSI buses, one for each set of eight disk slots. The remaining
SAC provides differential connection for an external SCSI device.
The processor and memory board contains the dual, lockstepped MIPS
microprocessors, the main memory system, and the secondary cache.