Mips Technologies R4000 - External Invalidate and Update Request Protocols

Chapter 12
348 MIPS R4000 Microprocessor User's Manual
External Invalidate and Update Request Protocols
External invalidate and update request protocols are the same as the
external write request protocol. The data element provided with an
update or invalidate request can be a doubleword, partial doubleword,
word, or partial word. The single data cycle transfer is not used (it does
not contain valid data) for an invalidate request.
Figure 12-33 illustrates an external invalidate request following an
uncompelled change to slave state.
NOTE: Timings for the SysADC and SysCmdP buses are the same as
those of the SysAD and SysCmd buses, respectively.
Figure 12-33 External Invalidate Request following an Uncompelled Change to Slave State
SCycle
1 2 3 4 5 6 7 8 9 10 11 12
SClock
SysAD Bus
Addr Unsd
SysCmd Bus
Ivd CEOD
ValidOut*
ValidIn*
ExtRqst*
Release*
Master Slave
Master
Slave