User`s guide

DWMBB/B Module Registers
Error Summary Register (BESR)
bit<2>
Name: VAXBI Interlock Read Failed
Mnemonic: None
Type: R/W1C, 0
VAXBI Interlock Read Failed sets to indicate that a VAXBI-to-XMI
memory Interlock Read operation failed to successfully complete on
the VAXBI. When this error occurs, it is probable that the lock set in
XMI memory will not be unlocked by the VAXBI device that issued
the Interlock Read. Timeout Address Register data is used by the
operating system to determine the locked address in XMI memory. The
operating system can then clear the lock. Clearing VAXBI Interlock
Read Failed also unlocks the Timeout Address Register.
VAXBI Interlock Read Failed sets whenever a VAXBI Interlock Read
command has been decoded and the summary EV code, Illegal CNF
Received for Slave Data (ICRSD) is decoded during a VAXBI Interlock
Read transaction. Setting BI Interlock Read Failed locks the contents
of the Timeout Address Register. Writing a one to VAXBI Interlock
Read Failed clears both the bit and its lock on the register.
When VAXBI Interlock Read Failed is set with its corresponding mask
bit, an error interrupt request is generated.
bit<1>
Name: IDENT Error
Mnemonic: IDENT ERR
Type: R/W1C, 0
IDENT Error sets to indicate that the DWMBB received an XMI
IDENT transaction and no VAXBI nor DWMBB interrupt requests
were pending at the IDENT transaction’s IPL. A set IDENT Error
indicates an error condition on the XMI bus with multiple IDENTs
being issued on the XMI for the same interrupt transaction. (Only
one XMI IDENT is issued on the XMI if a single interrupt targets
multiple CPUs.) All other CPUs that are waiting for an XMI bus grant
to issue their XMI IDENTs will cancel their IDENT transactions if
they see an IDENT transaction that matches the node ID and IPL
of the IDENT that they are waiting to issue. This error causes the
DWMBB/B module to notifiy the DWMBB/A module that the IDENT
failed. The DWMBB/A module then generates the appropriate error
response. IDENT Error does not set on a passive release from the
VAXBI.
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