IDT79R3081 RISController
MILITARY AND COMMERCIAL TEMPERATURE RANGES
Integrated Device Technology, Inc.
IDT79R3081
RISController
™
with FPA
IDT 79R3081™ , 79R3081E
IDT 79RV3081, 79RV3081E
FEATURES
• Instruction set compatible with IDT79R3000A, R3041,
R3051, and R3071 RISC CPUs
• High level of integration minimizes system cost
— R3000A Compatible CPU
— R3010A Compatible Floating Point Accelerator
— Optional R3000A compatible MMU
— Large Instruction Cache
— Large Data Cache
— Read/Write Buffers
• 43VUPS at 50MHz
— 13MFlops
• Flexible bus interface allows simple, low cost designs
• Optional 1x or 2x clock input
• 20 through 50MHz operation
• "V" version operates at 3.3V
• 50MHz at 1x clock input and 1/2 bus frequency only
• Large on-chip caches with user configurability
— 16kB Instruction Cache, 4kB Data Cache
— Dynamically configurable to 8kB Instruction Cache,
8kB Data Cache
— Parity protection over data and tag fields
• Low cost 84-pin packaging
• Superset pin- and software-compatible with R3051, R3071
• Multiplexed bus interface with support for low-cost, low-
speed memory systems with a high-speed CPU
• On-chip 4-deep write buffer eliminates memory write stalls
• On-chip 4-deep read buffer supports burst or simple block
reads
• On-chip DMA arbiter
• Hardware-based Cache Coherency Support
• Programmable power reduction mode
• Bus Interface can operate at half-processor frequency
R3081 BLOCK DIAGRAM
ClkIn
Clock Generator
Unit/Clock Doubler
Master Pipeline Control
System Control
Coprocessor
(CP0)
Exception/Control
Registers
Memory Management
Registers
Int(5:0)
BrCond(3:2,0)
Integer
CPU Core
General Registers
(32 x 32)
ALU
Shifter
Mult/Div Unit
Address Adder
PC Control
Virtual Address
FP Interrupt
Floating Point
Coprocessor
(CP1)
Register Unit
(16 x 64)
Exponent Unit
Add Unit
Divide Unit
Multiply Unit
Exception/Control
Translation
Lookaside Buffer
(64 entries)
Physical Address Bus
32
Data Bus
Configurable
Data
Cache
(4kB/8kB)
Configurable
Instruction
Cache
(16kB/8kB)
Data Bus
36
Parity
Generator
4-deep
Read
Buffer
R3051 Superset Bus Interface Unit
4-deep
Write
Buffer
DMA
Arbiter
BIU
Control
Coherency
Logic
Address/
Data
DMA
Ctrl
Rd/Wr
Ctrl
SysClk
Invalidate
Control
2889 drw 01
The IDT logo is a registered trademark, and RISController, R3041, R3051, R3052, R3071, R3081, R3720, R4400, R4600, IDT/kit, and IDT/sim are trademarks of Integrated Device Technology, Inc.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
©1995
Integrated Device Technology, Inc.
SEPTEMBER 1995
DSC-9064/4
5.5
5.5
1
IDT [ INTEGRATED DEVICE TECHNOLOGY ]
