PA-RISC Processors
PA-8200 (PCX-U+) processor
Overview
The PA-8200 is a 64-bit PA-RISC processor from HP that extended the original 64-bit PA-8000 soon after its release. Several aspects of the PA-8000 were improved with the PA-8200, released in 1997: branch prediction, TLB miss rates and cache sizes.
The PA-8200 should offer improved performace, compatibility with existing applications and short time to market.
The availability of new 4 Mb SRAMs with faster access times allowed for increased CPU speed and larger caches.
Smaller changes include an increase to the BHT and TLB as high benefit, low risk
improvements.
Details
- PA-RISC version 2.0, 64-bit architecture, multi-processor capable, 4-way superscalar
- Ten functional units: 2 integer ALUs, 2 shift/merge units, 2 complete load/store pipelines, 2 Floating Point multiply/accumulate units, 2 Floating Point divide/square root units
- IRB: 56-entry instruction queue/reorder buffer
- TLB: 120-entry fully-associative dual-ported
- BTAC: 42-entry Branch Target Address Cache; BHT: 1024-entry Branch History Table
- Cache 2 MB instruction and 2 MB data L1 off-chip, in synchronous 200 MHz 4 Mb SRAMs, one cycle latency
- Caches are direct-mapped and dual-ported
- Memory and I/O controllers are external
- Bi-endian support
- MAX-2 multimedia extensions subword arithmetic for multimedia applications
- Runway system bus, 120 MHz, 64-bit, about 960 MB/s peak bandwidth
- Up to 300 MHz, clock speed with 3.3 V core voltage
- 0.5µ, 5-layer metal CMOS
Used in
- HP 9000 C200, C240 workstations
- HP 9000 D390 servers
- HP 9000 J2240 workstations
- HP 9000 K370, K380, K570, K580 servers
- HP 9000 R390 servers
- HP 9000 V2200, V2250 mainframes
- HP 9000 NEC TX7/V2200 mainframes
References
- Four-Way Superscalar PA-RISC Processors (PDF, 190 KB) Anne P. Scott et al (August 1997: Hewlett-Packard Journal)
- HP Pumps Up PA-8x00 Family (archive.org mirror) Linley Gwennap (October 1994: Microprocessor Report, Volume 10 Number 14). [Article reprint for cpu.hp.com]
- HP's Latest PA-RISC Microprocessor Evolution Enables 50 Percent Application Performance Boost Hewlett-Packard (October 1996: HP press release). [Article mirror for hp.com]