Kontron AT8402 User Manual page 77

AT8402
4.4.1.1 IPMB Link Sensor
The AT8402 provides two IPMB links to increase communication reliability to the shelf manager
and other IPM devices on the IPMB. These IPMB links work together for increased throughput
where both busses are actively used for communication at any time. A request might be re-
ceived over IPMB Bus A, and the response is sent over IPMB Bus B. Any requests that time
out are retried on the redundant IPMB bus. In the event of any link state change, the events are
written to the AT8402 SEL. The IPMC monitors the bus for any link failure and isolates itself
from the bus if it detects that it is causing errors on the bus. Events are sent to signify the failure
of a bus or, conversely, the recovery of a bus.
4.4.1.2 FRU Hot Swap
The hot swap event message conveys the current state of the FRU, the previous state, and a
cause of the state change as can be determined by the IPMC. Refer to PICMG 3.0 Specifica-
tions for further details on the hot swap state.
4.4.1.3 CPU Status
The CPU Status is set if the PPC experiences a machine check error.
4.4.1.4 POSTCODE
The IPMC has access to the POSTCODE registers in the CPLD. Refer to section 4.3.1.2 (Boot
Steps)
4.4.1.5 Health Error
The Health Error is asserted if one of the sensors in Table 4-3: (AT8402 sensors) matches the
Health LED/Sensor condition.
4.4.2 Field Replaceable Unit (FRU) Information
This FRU information contains the IPMI defined Board and Product Information areas that hold
the part number and serial number of the board and the Multirecord Information Area that con-
tains the PICMG defined Point to Point Information records.
The Internal Use Area is preallocated to 384 bytes and is free for customer use.
This FRU information responds to FRU ID #0, which is the ID for the IPMC.
Software Description
Page 4 - 13 AT8402 User Guide