Octel XC1000, Руководство по обслуживанию

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STATUS LOG
7-8 Edition One XC1000 Service
Table 7-4 is located at the end of the chapter on a foldout page,
following Table 7-2 and Table 7-3. The table is required through-
out the chapter when interpreting the status codes in section
7.3. Leave Table 7-4 folded out for easy reference when using
section 7.3.
Second byte (offset 01 in the CB message). The second byte of a
CB message is the destination, indicating the card to which the CPU
is sending the message. If the destination is a TIC port or DLC
channel, the high-order nibble indicates the logical channel number of
the TIC port, and the low-order nibble indicates the logical slot
address. If the destination is a common-control card, the high-order
nibble contains the bank number, and the lower-order nibble contains
the logical slot number.
Instead of attempting to use this byte to determine the destination,
use the IORB peripheral address located elsewhere in the status-log
entry to quickly identify the destination card. Refer to Section 7.2.3
for an explanation of the IORB peripheral address.
Third byte (offset 02 in the CB message). The third byte of a CB
message is the message type, which indicates the command that the
CPU wants the card to perform. There are many commands, too
numerous to list here. However, with just a few common commands, it
is possible to determine XC1000 activity when the status entry was
logged. The message type determines the remainder of the 16-byte CB
message. Table 7-5 provides a list of the most common CB message
types.
Table 7-5 is located at the end of the chapter on a foldout page,
following Table 7-4. The table is required throughout the
chapter when interpreting the status codes in section 7.3. Leave
Table 7-5 folded out for easy reference when using section 7.3.
1. Use Table 7-5 to interpret the CB messages. The IORB peripher-
al address determined by decoding other offsets in a status-log
entry indicates which portion of Table 7-5 to use: the file-card
or DLC portion. Usually, only the file-card messages provide
useful information. File-card CB messages are displayed in
status-code 70 and 72 entries (file system drive I/O error and
scramble code error or I/O error during message operation,
respectively).
2. Refer to Figure 7-5, where the CPU is instructing the message
file card, recorded in the CB OUT message. The CPU instructs
the message file card to perform the command to read the
message buffer, which is logged as code
2A. In the CB IN
message, the message-file card notifies the CPU that it received
the read message-buffer-response command logged as
2B.
Fourth byte (offset 03 in the CB message). The fourth byte of a CB
message is the return code. The return code is unique to the CB IN
message and is used to determine the success or failure of an operation.
The meaning of the value in a return code varies with different status-log
entries and is defined in each status-code description in this chapter.
SECTION 7.2