Computer Hardware User Manual

Architecture
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6.2.6 BadVAddr (Bad Virtual Address) register (register no.8)
When an Address Error exception (AdEL or AdES) is raised, the virtual address that caused the error
is saved in the BadVAddr register.
When a TLB Refill, TLB Modified or UTLB Refill exception is raised, the virtual address for which
address translation failed is saved in BadVaddr.
BadVaddr is a read-only register.
Note : A bus error is not the same as an Address Error and does not cause information to be saved
in BadVaddr.
31 0
Bad Virtual Address
6.2.7 PRId (Processor Revision Identifier) register (register no.15)
PRId is a 32-bit read-only register, containing information concerning the implementation and
revision level of the processor and system control coprocessor (CP0).
The register format is shown in Figure 6-9.
31 16 15 8 7 0
0 Imp Rev
16 8 8
Bits Mnemonic Field name Description
Value on
Reset
Read/
Write
15-8 Imp Implementation
number
R3900 Processor Core ID 0x22 Read
7-0 Rev Revision
identifier
R3900 Processor Core revision ID
†
†
Read
31-16 0 Ignored on write; 0 when read. 0 Read
†
Value is shown in product sheet.
Figure 6-9. PRId register
Figure 6-8. BadVaddr register