MC68030FE20C Freescale Semiconductor, MC68030FE20C Datasheet - Page 146

• Manufacturer Part Number: MC68030FE20C
• Description: IC MPU 32BIT ENHANCED 132-CQFP
• Manufacturer: Freescale Semiconductor

Specifications of MC68030FE20C

• Processor Type: M680x0 32-Bit
• Speed: 20MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 132-CQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

M O T O R O L A
LOGICAL ADDRESS = FC2-FCO, A31-A8, A7-A4, A3-A2
SELECT
LINE
($5)
that when CLOUT is asserted, the data cache is completely ignored, even on
and is stale. Since the write-allocation mode updates the cache during write
cycles, the data in the cache remains consistent with physical memory. Note
write cycles operating in the write-allocation mode. Also note that since the
CIIN signal is ignored on write cycles, cache entries may be created for
write-allocation mode. Figure 6-4 shows the manner in which each mode
operates in five different situations.
In this case, the data in the cache no longer matches that in physical memory
noncachable data (when CIIN is asserted on a write) when operating in the
Figure 6-4. No-Write-Allocation and Write-Allocation Mode Examples
EXAMPLE 1:
EXAMPLE 2:
EXAMPLE 3:
EXAMPLE 4:
EXAMPLE 5:
USER LONG WORD WRITE OF b6'-b9'TO $00002056
USER WORD WRITE OF b2"-b3' TO $00001052
USER LONG WORD WRITE OF b6'-b9' TO $00001056
USER LONG WORD WRITE OF b4'-b7' TO $00001054
USER LONG WORD WRITE OF b4'-b7' TO $00002054
(NO TAG MATCH, LONG WORD DATA, MISAUGNED)
(CACHE HIT. ALWAYS UPDATE CACHE AND MEMORY)
(TAB MATCH, LONG WORD DATA, MISALIGNED,
b6-b7 RESULT IN A CACHE MISS.
b8-b9 RESULT IN A CACHE HIT)
(TAG MATCH, CACHE MISS, LONG WORD DATA,
LONG WORD ALIGNED)
(NO TAG MATCH, LONG WORD DATA. LONG WORD ALIGNED)
I
USER DATA. $000010 I
TAG'
I
TAG
I
q----T--
M C 6 8 0 3 0
[
U S E R ' S
1L ,.,.v,:o 1L .o,V :lj [
M A N U A L
A) START EXTERNAL CYCLE
A) START EXTERNAL CYCLE
R) b2-b3~-b2'-b3 '
A) START EXTERNAL CYCLE
B) bS-b9"~-b8'-b9'
A) START EXTERNAL CYCLE
A) START EXTERNAL CYCLE
ENTRY SELECT
NO WRITE.ALLOCATE
A) START EXTERNAL CYCLE
A) START EXTERNAL CYCLE
A) START EXTERNAL CYCLE
A) START EXTERNAL CYCLE
A) START EXTERNAL CYCLE
B) V2 ~-" 0
B) b2-b3"~-b2'-b3'
B) b8-b9-~-bG'-b9'
B) b4-b7-~- b4'-bT"
C) V1 ~ - - 1
B) TAG-~- TAG'
C) b4-b7~- b4'-b7"
D) V0~4{ -- 0
VI~E- 1
V2"~- O
V3 -qE- 0
WRITE ALLOCATE
6 - 9
j
6