Acorn J233
.jpg) | |
| Acorn's brochure photograph of the J233 | |
| Specifications | |
|---|---|
| Manufacturer | Acorn Computers |
| Type | Desktop computer |
| Released | September 1997[1] |
| CPU | StrongARM at 233 MHz |
| Memory | 32 MB DRAM (one further SIMM socket); 2 MB VRAM |
| Storage | 1.7 GB IDE hard disc; 1.6 MB 3.5-inch floppy; x24 ATAPI CD-ROM |
| Display | VIDC20, up to 1280 × 1024 at 256 colours |
| Sound | 16-bit stereo |
| ROM | 4 MB, RISC OS 3.7 |
| Power | Integral 103 W switched-mode supply, switchable 110 to 240 V AC |
| Dimensions | 355 × 383 × 117 mm (one slice) |
| Weight | About 3.75 kg |
| OS / Firmware | — |
| Model no. | SRP41 |
The Acorn J233 StrongARM Risc PC is a version of Acorn's 233 MHz StrongARM Risc PC sold from September 1997 with Acorn's web browser and a Java virtual machine installed on the hard disc. Chris Whytehead records that the bundled software was the only difference from the standard 233 MHz StrongARM Risc PC launched at the same time, and that the software was also sold separately on the Browse and Riscafe update CDs. Its sales code was SRP41, "J233 Java Risc PC".[1][2]
Specification
[edit | edit source]| Area | Detail |
|---|---|
| Processor | StrongARM at 233 MHz; OpenBus slot for a 486/5x86 PC card |
| Chip set | IOMD I/O and memory controller; VIDC20 video controller |
| Memory | 32 MB DRAM, one further SIMM socket; 2 MB VRAM; 240 bytes of battery-backed CMOS RAM; 48-bit unique identifier |
| ROM | 4 MB page-mode ROM with RISC OS 3.7 |
| Expansion | Two 32-bit EASI slots per slice, up to eight in total; dedicated network card slot |
| Drives | 1.7 GB IDE hard disc; 1.6 MB 3.5-inch floppy; x24 ATAPI CD-ROM |
| Ports | 9-pin RS232; 25-pin parallel; 15-way high-density monitor; internal genlock port; 3.5 mm stereo output for 32 ohm headphones or line level |
| Software | Java 1.0.2 virtual machine; HTML 3.2 browser; mail and news clients; Omniclient II network access |
| Input | 102-key PS/2 keyboard; three-button PS/2 mouse |
| Power | Integral 103 W switched-mode supply with IEC inlet and outlet, switchable 110 to 240 V, 50 or 60 Hz |
Source: Acorn's leaflet.[2] Chris Whytehead gives RISC OS 3.71 for the September 1997 machines; the leaflet says RISC OS 3.7.[1][2]
Wikipedia's Risc PC timeline also places the J233, with a 233 MHz StrongARM and the browser and Java software, in 1997.[3]
Hardware and repair
[edit | edit source]The J233 is built on the same Risc PC architecture as the Acorn Risc PC 600 and Acorn Risc PC 700: the IOMD and VIDC20 chips, EASI podule slots in stacking slices, a separate network slot and a 103 W supply.[2] The StrongARM processor is on a plug-in CPU card. Chris Whytehead's own 233 MHz StrongARM Risc PC (an SRP26, not a J233) has main board 1208,000 issue 3, the board used in the Risc PC 700, with RISC OS 3.70 ROMs, a Sony CD-ROM and floppy drive and a 103 W supply.[4] The Risc PC 700 guides cover the shared hardware:
- Acorn Risc PC 700 Maintenance Guide: safety, the backup battery, the surface-mount capacitors and the hard disc.
- Acorn Risc PC 700 Troubleshooting Guide: self-test codes, power faults, "CMOS unreadable" and lost settings, leaking capacitors.
- Acorn Risc PC 700 Capacitor Guide: which surface-mount electrolytics leak, and Acorn's reference list for the earlier 0197,000 board.
Acorn's Risc PC Technical Reference Manual describes the IOMD/VIDC20 system, the backplanes, the power supply and the power-on self test; it predates the StrongARM card.[5] Like other Risc PCs, the StrongARM machines are held back by the 16 MHz system bus when the processor works from main memory.[3]
Documentation
[edit | edit source]- Acorn J233 StrongARM Risc PC leaflet (AGP24.79.50, 1997).[2]
- Acorn Risc PC Technical Reference Manual.[5]
Related pages
[edit | edit source]References
[edit | edit source]- ↑ 1.0 1.1 1.2 Whytehead, Chris. "Acorn J233 StrongARM Risc PC", Chris's Acorns, The Centre for Computing History (retrieved 2026-10-02). Launched September 1997 alongside the upgraded StrongARM Risc PC (233 MHz StrongARM, RISC OS 3.71, more memory, larger disc, CD-ROM); the only difference was the bundled !Browse and Java on the hard disc; model SRP41 "J233 Java Risc PC".
- ↑ 2.0 2.1 2.2 2.3 2.4 Acorn Computers, Acorn J233 StrongARM Risc PC, leaflet AGP24.79.50, 1997. Hosted on this wiki: File:Acorn J233 StrongARM Risc PC brochure (AGP24.79.50).pdf. Feature list p. 1; Java and web browser p. 2; technical overview p. 4 (processor, OpenBus PC card slot, IOMD and VIDC20, memory, ROM, CMOS RAM, unique identifier, expansion slots, network slot, drives, ports, screen modes, software, dimensions, weight, 103 W supply, approvals).
- ↑ 3.0 3.1 "Risc PC", Wikipedia (retrieved 2026-10-02), timeline: 1996 200 MHz StrongARM upgrade; 1997 "Acorn launch Acorn J233 StrongARM Risc PC, featuring an uprated 233 MHz model of StrongARM and including Browser and Java software"; the 16 MHz system bus as the design's main limit with StrongARM.
- ↑ Whytehead, Chris. "Acorn StrongARM Risc PC", Chris's Acorns (retrieved 2026-10-02). StrongARM Risc PC model list (SRP05 to SRP26); his SRP26 233 MHz machine: Acorn 233 MHz StrongARM CPU card, issue 3 main board 1208,000 with 16-bit sound, IOMD21, VIDC20, SMC FDC37C665GT, RISC OS 3.70 ROMs, Sony CDU311 CD-ROM, Sony MPF920-H floppy drive with its front flap spring broken, Seagate ST31276 hard disc, 103 W supply; some CPU cards were 160 MHz parts overclocked to 202 MHz.
- ↑ 5.0 5.1 Acorn Computers, Risc PC Technical Reference Manual, part no. 0497,057, issue 1, September 1994, hosted on this wiki.