MPC8544COMEDEV Freescale Semiconductor, MPC8544COMEDEV Datasheet - Page 275

• Manufacturer Part Number: MPC8544COMEDEV
• Description: KIT DEV EXPRESS MPC8544COM
• Manufacturer: Freescale Semiconductor
• Type: MPUr

Specifications of MPC8544COMEDEV

• Contents: Board
• For Use With/related Products: MPC8544
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.2.1
Figure 7-3
Physical address bits 21–30 identify the bank and set of the tag and data. Physical address bits 0–20 are
compared against the tags of all eight ways. A match of a valid tag selects a 32-byte block of data (or way)
within the set. Physical address bits 31–35 identify the byte or bytes of data within the block.
7.2.2
When all or part of the array is dedicated to memory mapped SRAM, individual ways of each set are
reserved for that purpose. SRAM accesses use physical address bits 18–20 in conjunction with the SRAM
mode to select a way of the indexed set.
Freescale Semiconductor
Tag Lookup
Way Select
Data Read/Write
shows how physical address bits are used to access the L2 cache.
Accessing the On-Chip Array as an L2 Cache
Accessing the On-Chip Array as an SRAM
MPC8544E PowerQUICC III Integrated Host Processor Family Reference Manual, Rev. 1
Figure 7-3. Physical Address Usage for L2 Cache Accesses
Bank select
21
0
21
Bank select
22 23
22 23
ADDR
ADDR
Set index
Set index
(8 bits)
(8 bits)
ADDR
Tags (21 bits)
30
30
Tag Compare
Way select
(3 bits)
Way
31
20
Byte select
(5 bits)
ADDR
35
8 Tags per Set
L2 Look-Aside Cache/SRAM
7-5