
PRELIMINAR
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MOTOROLA
EC603e Microprocessor Hardware Specifications (PID7v)
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PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
1.2 Features
This section summarizes features of the PID7v’s implementation of the PowerPC architecture. Major
features of the PID7v are as follows:
High-performance, superscalar microprocessor
— As many as three instructions issued and retired per clock
— As many as ve instructions in execution per clock
— Single-cycle execution for most instructions
Four independent execution units and one register le
— BPU featuring static branch prediction
— A 32-bit IU
— LSU for data transfer between data cache and GPRs
— SRU that executes condition register (CR), special-purpose register (SPR) instructions, and
integer add/compare instructions
— Thirty-two GPRs for integer operands
High instruction and data throughput
— Zero-cycle branch capability (branch folding)
— Programmable static branch prediction on unresolved conditional branches
— Instruction fetch unit capable of fetching two instructions per clock from the instruction cache
— A six-entry instruction queue that provides lookahead capability
— Independent pipelines with feed-forwarding that reduces data dependencies in hardware
— 16-Kbyte data cache—four-way set-associative, physically addressed; LRU replacement
algorithm
— 16-Kbyte instruction cache—four-way set-associative, physically addressed; LRU replacement
algorithm
— Cache write-back or write-through operation programmable on a per page or per block basis
— BPU that performs CR lookahead operations
— Address translation facilities for 4-Kbyte page size, variable block size, and 256-Mbyte
segment size
— A 64-entry, two-way set-associative ITLB
— A 64-entry, two-way set-associative DTLB
— Four-entry data and instruction BAT arrays providing 128-Kbyte to 256-Mbyte blocks
— Software table search operations and updates supported through fast trap mechanism
— 52-bit virtual address; 32-bit physical address
Facilities for enhanced system performance
— A 32- or 64-bit split-transaction external data bus with burst transfers
— Support for one-level address pipelining and out-of-order bus transactions
Integrated power management
— Low-power 2.5/3.3-volt design
— Internal processor/bus clock multiplier that provides 2/1, 2.5/1, 3/1, 3.5/1, 4/1, 4.5/1, 5/1,
5.5/1, and 6/1 ratios
— Three power saving modes: doze, nap, and sleep
— Automatic dynamic power reduction when internal functional units are idle
In-system testability and debugging features through JTAG boundary-scan capability