Features
Table 1 shows the functionality supported by the members of the MPC885 family.
Table 1. MPC885 Family
Cache
Ethernet
Security
Engine
Part
SCC SMC USB
ATM Support
I Cache D Cache 10BaseT 10/100
MPC885
8 Kbyte 8 Kbyte Up to 3
8 Kbyte 8 Kbyte Up to 2
2
2
3
2
2
2
1
1
Serial ATM and
UTOPIA interface
Yes
No
MPC880
Serial ATM and
UTOPIA interface
2 Features
The MPC885/880 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 MPC885/880 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 PowerPC 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
•
Provides enhanced ATM functionality found on the MPC862 and MPC866 families and includes the
following:
— Improved operation, administration and maintenance (OAM) support
— OAM performance monitoring (PM) support
— Multiple APC priority levels available to support a range of traffic pace requirements
— Port-to-port switching capability without the need for RAM-based microcode
— Simultaneous MII (100BaseT) and UTOPIA (half- or full -duplex) capability
— Optional statistical cell counters per PHY
MPC885/MPC880 Hardware Specifications, Rev. 3
2
Freescale Semiconductor
FREESCALE [ Freescale ]
