
MPC875/MPC870 PowerQUICC Hardware Specifications, Rev. 4
2
Freescale Semiconductor
Overview
1Overview
The MPC875/MPC870 is a versatile single-chip integrated microprocessor and peripheral combination
that can be used in a variety of controller applications and communications and networking systems. The
MPC875/MPC870 provides enhanced ATM functionality over that of other ATM-enabled members of the
MPC860 family.
Table 1 shows the functionality supported by the MPC875/MPC870.
2Features
The MPC875/MPC870 is comprised of three modules that each use the 32-bit internal bus: a MPC8xx
core, a system integration unit (SIU), and a communications processor module (CPM).
The following list summarizes the key MPC875/MPC870 features:
Embedded MPC8xx core up to 133 MHz
Maximum frequency operation of the external bus is 80 MHz (in 1:1 mode)
— The 133-MHz core frequency supports 2:1 mode only
— The 66-/80-MHz core frequencies support both the 1:1 and 2:1 modes
Single-issue, 32-bit core (compatible with the Power Architecture definition) with thirty-two
32-bit general-purpose registers (GPRs)
— The core performs branch prediction with conditional prefetch and without conditional
execution
— 8-Kbyte data cache and 8-Kbyte instruction cache (see
Table 1)– Instruction cache is two-way, set-associative with 256 sets in 2 blocks
– Data cache is two-way, set-associative with 256 sets
– Cache coherency for both instruction and data caches is maintained on 128-bit (4-word)
cache blocks
– Caches are physically addressed, implement a least recently used (LRU) replacement
algorithm, and are lockable on a cache block basis
— MMUs with 32-entry TLB, fully associative instruction and data TLBs
— MMUs support multiple page sizes of 4, 16, and 512 Kbytes, and 8 Mbytes; 16 virtual address
spaces and 16 protection groups
— Advanced on-chip emulation debug mode
Up to 32-bit data bus (dynamic bus sizing for 8, 16, and 32 bits)
Table 1. MPC875/MPC870 Devices
Part
Cache (Kbytes)
Ethernet
SCC
SMC
USB
Security
Engine
I Cache
D Cache
10BaseT
10/100
MPC875
8812
1
Yes
MPC870
8
—
2
—
1
No