Acorn Risc PC 700
| Acorn Risc PC (slice case; the 700 is externally identical to the 600) | |
| Specifications | |
|---|---|
| Manufacturer | Acorn Computers Ltd |
| Type | Personal computer |
| Released | July 1995 |
| CPU | ARM710 @ 40 MHz |
| Memory | DRAM via 72-pin SIMMs (up to 256 MB) + 1–2 MB VRAM (standard) |
| Storage | On-board IDE hard disc, 3.5" floppy, optional CD-ROM |
| Display | VIDC20, up to 16.7 million colours |
| Sound | 8-channel 16-bit (standard) |
| OS / Firmware | RISC OS 3.60 |
| Predecessor | Acorn Risc PC 600 |
| Successor | StrongARM Risc PC |
| Model no. | ACB70, ACB75, ACB76, ACB77 (and variants) |
The Acorn Risc PC 700 was launched in July 1995 as an iterative upgrade of the Acorn Risc PC 600. It fitted the faster 40 MHz ARM710 processor, made VRAM and 16-bit sound standard, and shipped with RISC OS 3.60. The ARM710 gives roughly a 40% improvement over the original 30 MHz ARM610 of the 600.[1]
Relationship to the Risc PC 600
The Risc PC 700 shares the Risc PC architecture and slice case with the 600: the same IOMD memory-and-I/O controller, VIDC20 video-and-sound controller, SMC FDC37C665 'Combo' peripheral controller, plug-in CPU card with a second processor socket, 72-pin DRAM SIMMs, VRAM, on-board IDE and floppy, two podule slots plus a network slot, and a PC-AT keyboard.[2] The visible differences are the faster CPU card, the RISC OS 3.60 ROMs, VRAM fitted as standard, on-board 16-bit sound, and larger hard discs.
| Function | Device |
|---|---|
| CPU | ARM710 @ 40 MHz (on a plug-in CPU card) |
| Memory + I/O controller | IOMD |
| Video and sound | VIDC20 (16-bit sound standard) |
| Peripheral 'Combo' controller | SMC FDC37C665 (floppy, IDE, serial, parallel) |
Board
The Risc PC 700 main PCB is part 1208,000, a revision of the 600's 0197,000 board that incorporates the 16-bit sound circuitry. As on the 600, the board carries on-board SMD fuses and a NiMH backup battery for the CMOS configuration, and accepts later StrongARM CPU cards (RISC OS 3.70) and x86 PC cards.[1][3]
Models
The 700 range included the ACB70/ACB71 (4 MB, 1 MB VRAM), the ACB75/ACB76 series (8 MB, 2 MB VRAM, 850 MB–1 GB discs, with and without CD-ROM), the ACB77/ACB78 (4 MB, 1 MB VRAM, 540 MB) and the ACB96 X-system. Later machines were fitted with StrongARM CPU cards and RISC OS 3.70/3.71.[1]
Maintenance and repair
The Risc PC 700 shares the Risc PC's surface-mount electrolytic-capacitor problem (leakage and board corrosion). See the dedicated pages:
- Acorn Risc PC 700 Maintenance Guide
- Acorn Risc PC 700 Troubleshooting Guide
- Acorn Risc PC 700 Capacitor Guide
See also
References
- โ 1.0 1.1 1.2 Whytehead, Chris. "Acorn Risc PC 700", Chris's Acorns / The Centre for Computing History. Source for the launch date, the 40 MHz ARM710, RISC OS 3.60, VRAM/16-bit sound as standard, the ~40% performance gain, the model list (ACB70–ACB96), and the board part number (1208,000).
- โ "The Acorn Risc PC and A7000", 4corn Computers. Source for the 40 MHz ARM710, the VRAM/16-bit-sound-as-standard change, and the shared Risc PC architecture; also the later StrongARM CPU card (RISC OS 3.70).
- โ Acorn Risc PC Technical Reference Manual (Issue 1, September 1994; part 0497,057), Acorn Computers — hosted on this wiki. Covers the shared Risc PC architecture, the main-PCB parts list, the on-board fuses and NiMH battery, and the Power On Self Test. The TRM documents the original (0197,000) board; the 700's 1208,000 board is a revision.