mcf5282 Freescale Semiconductor, Inc, mcf5282 Datasheet - Page 108

• Manufacturer Part Number: mcf5282
• Manufacturer: Freescale Semiconductor, Inc

Cache
For instruction fetches, the fill buffer can also be used as temporary storage for line-sized bursts of
non-cacheable references under control of CACR[CEIB]. With this bit set, a non-cacheable instruction
fetch is processed, as defined by
references can hit in the buffer, but the data is never loaded into the memory array.
Table 4-7
4-10
shows the relationship between CACR bits CENB and CEIB and the type of instruction fetch.
[CENB]
CACR
0
0
1
1
1
[CEIB]
CACR
Table 4-7. Instruction Cache Operation as Defined by CACR
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3
X
0
1
0
1
Instruction Fetch
Non-cacheable
Non-cacheable
Table
Cacheable
Type of
N/A
N/A
4-7. For this condition, the line-fill buffer is loaded and subsequent
Cache is completely disabled; all instruction fetches
are word or longword in size.
All instruction fetches are word or longword in size
Fetch size is defined by
line-fill buffer can be written into the memory array
All instruction fetches are word or longword in size,
and not loaded into the line-fill buffer
Instruction fetch size is defined by
loaded into the line-fill buffer, but are never written into
the memory array.
Description
Table 4-6
and contents of the
Table 4-6
Freescale Semiconductor
and