mpc755ed Freescale Semiconductor, Inc, mpc755ed Datasheet - Page 3

• Manufacturer Part Number: mpc755ed
• Description: Risc Microprocessor Hardware Specifications
• Manufacturer: Freescale Semiconductor, Inc

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This section summarizes features of the MPC755 implementation of the PowerPC architecture. Major
features of the MPC755 are as follows:
Freescale Semiconductor
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Features
Branch processing unit
— Four instructions fetched per clock
— One branch processed per cycle (plus resolving two speculations)
— Up to one speculative stream in execution, one additional speculative stream in fetch
— 512-entry branch history table (BHT) for dynamic prediction
— 64-entry, four-way set-associative branch target instruction cache (BTIC) for eliminating
Dispatch unit
— Full hardware detection of dependencies (resolved in the execution units)
— Dispatch two instructions to six independent units (system, branch, load/store, fixed-point
— Serialization control (predispatch, postdispatch, execution serialization)
Decode
— Register file access
— Forwarding control
— Partial instruction decode
Completion
— Six-entry completion buffer
— Instruction tracking and peak completion of two instructions per cycle
— Completion of instructions in program order while supporting out-of-order instruction
Fixed point units (FXUs) that share 32 GPRs for integer operands
— Fixed Point Unit 1 (FXU1)—multiply, divide, shift, rotate, arithmetic, logical
— Fixed Point Unit 2 (FXU2)—shift, rotate, arithmetic, logical
— Single-cycle arithmetic, shifts, rotates, logical
— Multiply and divide support (multi-cycle)
— Early out multiply
Floating-point unit and a 32-entry FPR file
— Support for IEEE standard 754 single- and double-precision floating-point arithmetic
— Hardware support for divide
— Hardware support for denormalized numbers
— Single-entry reservation station
— Supports non-IEEE mode for time-critical operations
— Three-cycle latency, one-cycle throughput, single-precision multiply-add
branch delay slots
unit 1, fixed-point unit 2, floating-point)
execution, completion serialization, and all instruction flow changes
MPC755 RISC Microprocessor Hardware Specifications, Rev. 8
Features
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