Octel XC1000, Руководство по обслуживанию

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STATUS LOG
7-7 Edition One XC1000 Service
7.2.4 Control-Bus Messages
The CPU uses the control bus to manage all logic cards except TICs. DLCs
provide the interface between the CPU and the TICs. The CPU tells the
cards what to do, based on the port to which a caller is connected and the
action of the caller.
All control-bus (CB) messages are sent to and from the CPU. The other
cards cannot send CB messages directly to each other. The CPU communi-
cates with other cards, using a command–response protocol. The CPU
sends commands through CB OUT messages. Other cards send responses
to the CPU through CB IN messages.
Not all status-log entries contain CB messages. When status-log entries
contain CB messages, the messages occur at different locations in the
body of the status-log entry, depending on the status code.
However,
CB messages commonly begin at offsets 34 and 44 or 30 and 40. To
assist in interpreting a status-code entry, the location of the CB message,
where present, is provided in each frequently logged status code described
in section 7.3.
When a CB message is logged to the destination (CB OUT) in a status-log
entry, the response from the destination (CB IN) begins at the 16th hexa-
decimal byte following (or, directly underneath) the beginning of the CB
OUT message. For example, if a CB OUT message starts at offset 34, the
CB IN message begins at offset 44. The value at offsets 34 and 44 is the
task/source; the value at offsets 35 and 45 is the destination; the value at
offsets 36 and 46 is the message type. Figure 7-5 is an example of a CB
message.
0F 01 2A 00 00 00 00 00 00 00 00 00 00 00 00 00
0F 01 2B 01 00 5C 4E 22 03 64 F4 9D 02 00 00 00
MESSAGE TYPE
DESTINATION
TASK/SOURCE
CB OUT (OFFSET 34)
CB IN (OFFSET 44)
OFFSET*
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
* Within the CB message.
RETURN CODE (CB IN ONLY)
Figure 7-5. Example of Control-Bus Message Format.
Refer to Figure 7-5 and consider the following bytes of a CB message when
evaluating a status-log entry:
First byte (offset 00 in the CB message). The first byte of a CB
message is the task/source identification. The task/source is the
segment of the CPU code that controls the currently active process.
The first byte can usually be related to the port to which the caller is
connected.
Match the entry in the Task/Source column with the Port column in
Table 7-4 to determine this port. For example, the value 0F in offset
00 corresponds to port 2D.
SECTION 7.2