MC68LC040RC25A Datasheet, PDF (203/442 Pages) Freescale Semiconductor, Inc – M68040 Users Manual

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C1
C2
C3
C1
C2
C3
BCLK
SC1, SC0
A31–A0
SIZ1, SIZ0
TT1, TT0
R/W
TS
MI
TA
D31–D0
BR
BG
BB
AM_BR*
AM_BG*
PROCESSOR
* AM indicates the alternate bus master.
Undefined
ALTERNATE
MASTER
PROCESSOR
Figure 7-40. Snoop-Inhibited Bus Cycle
7.9.2 Snoop-Enabled Cycle (No Intervention Required)
For alternate bus master accesses in which SCx = $1 or $2, indicating that snooping is
enabled, the M68040 continues to assert MI while checking for a matching cache line. If
intervention in the alternate bus master access is not required, MI is then negated, and
memory is allowed to respond and complete the access. Figure 7-41 illustrates an
example of snooping in which memory is allowed to respond. Best-case timing is
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