User`s guide

DWMBB Adapter
3.12.5.9 IDENT IBUS Parity Error
If the DWMBB/B module detects an IBUS parity error during an IDENT
cycle, then it does the following:
• Sets DWMBB/B-Detected IBUS Parity Error (BESR<0>)
• Sets Command/Address Fetch Failed (BESR<6>)
• Sets Master Sequencer Transaction Failed (BESR<4>)
• Aborts the transaction
• Informs the DWMBB/A module that the I/O transaction failed
The DWMBB/A module then returns the contents of ARVR to the
requesting XMI node, unless Return Vector Disable (ACSR<1>) is set.
If Return Vector Disable is set and the DWMBB/B module had detected
the IBUS parity error on an IDENT C/A cycle, the DWMBB/A module
returns an RER to the requesting node.
3.12.5.10 Undecodable I/O C/A with no IBUS Parity Error Detected
If a reserved or illegal command is decoded and DWMBB/B-Detected
IBUS Parity Error (BESR<0>) is not set, the DWMBB/B module does the
following:
• Sets Illegal I/O Command (BESR<3>)
• Aborts the transaction
• Informs the DWMBB/A module that the I/O transaction failed
The DWMBB/A module then does the following if its "I/O Read Flag" is not
set:
• Sets I/O Write Failure (AESR<6>)
• Logs the address of the I/O command in AREAR<29:0>
• Generates an IVINTR if Enable IVINTR Transactions (AIMR<31>) is
set
The DWMBB/A module returns an RER to the requesting XMI commander
node, if its "I/O Read Flag" is set.
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