Psion Series 5mx
 | |
| Two Series 5mx palmtops, one open and one closed | |
| Specifications | |
|---|---|
| Developer | Psion Computers PLC |
| Manufacturer | Psion Computers PLC |
| Type | Clamshell palmtop computer |
| Released | 1999 |
| CPU | ARM710T core in Psion's "Windermere" system-on-chip, 36.864 MHz |
| Memory | 10 MB ROM; 16 MB RAM (8 MB on some models) |
| Storage | Internal RAM disk; CompactFlash Type I slot |
| Display | 640 × 240 backlit LCD, 16 grey levels, with a resistive digitiser |
| Sound | ½ W 8 Ω loudspeaker; electret microphone |
| Dimensions | 172 mm × 89 mm × 24 mm |
| Weight | 350 g with batteries |
| OS / Firmware | EPOC32 (later renamed Symbian OS) |
| Predecessor | Psion Series 5 |
| Model no. | Series 5mx; Series 5mx Pro; Ericsson MC218 |
The Psion Series 5mx is a clamshell palmtop computer made by Psion Computers PLC and released in 1999 as the successor to the Psion Series 5. It has a faster processor, a clearer screen and updated software, in a case that looks almost the same as the Series 5's.[1] Opening the lid slides the keyboard forward to counterbalance the screen, so that pressing the touchscreen does not tip the machine over.[1]
History
[edit | edit source]The sliding case was designed by Martin Riddiford of Therefore Design for the Series 5 and is covered by European patent EP 0766166.[1] The 5mx followed the Series 5 in 1999.[1] Psion also sold the Series 5mx Pro, which loads its operating system from a file on CompactFlash so that it can be upgraded, and Ericsson sold the 5mx as the MC218.[1][2] An Executive Edition was bundled with extras including version 3.62 of the Opera web browser.[1]
Architecture and processor
[edit | edit source]The 5mx is built around "Windermere", a Psion system-on-chip with an ARM710T core.[2] Psion's user guide gives the clock as 36.864 MHz.[3] The Series 5 used a Cirrus Logic CL-PS7110 with an ARM710a core at 18.432 MHz; the ARM710T adds the Thumb instruction set, more multiply instructions and changes to coprocessor 15.[2] The CompactFlash and PCMCIA interface is handled by a Psion chip known as Etna, present in both the Series 5 and the 5mx, for which almost no documentation has surfaced.[2]
The 5mx also carries a 128-byte PROM holding its serial number and its factory digitiser and real-time clock calibration. EPOC reads it one bit at a time through GPIO and Etna registers and checks it with an XOR checksum.[2]
Memory and storage
[edit | edit source]The specification in Psion's user guide gives 10 MB of ROM and 16 MB of RAM, and notes that memory configurations vary by model; 8 MB models were also sold.[3][2] The operating system is in ROM and user files are held on an internal RAM disk, so the machine depends on its batteries to keep them.[2][3] The CompactFlash slot takes Type I cards, including Psion Memory Disks.[3]
Display
[edit | edit source]The screen is a 640 × 240 LCD with 16 grey levels and a backlight, under a resistive touch digitiser.[1] On the Series 5, whose display construction the service manual describes, the digitiser is a glass lower plate and a hard plastic upper plate with resistive ink on their inner faces, and the LCD supply rails must be switched in a set order so that no DC is left across the panel.[4] The touch coordinates start at the top left of the LCD, not of the digitiser, so the printed shortcut icons to the left of the screen have negative X coordinates.[2]
Battery voltages and the digitiser position are read through an ADC on the SPI bus, with four channels on the 5mx.[2]
| Channel | Identifier |
|---|---|
| Digitiser Y | 0x9093 |
| Digitiser X | 0xD0D3 |
| Main battery | 0xA4A4 |
| Backup battery | 0xE4E4 |
Sound
[edit | edit source]The 5mx has a ½ W, 8 Ω loudspeaker and an electret microphone with automatic gain control, used by the voice recorder.[3]
Input, output and expansion
[edit | edit source]The keyboard has 53 keys in a QWERTY layout, with a 12.5 mm key pitch.[3][1] Nine touch-sensitive icons beside the screen select programs and five select commands.[3] The operating system scans the keyboard by column, selecting a column through the KSCAN register and reading the rows from GPIO port A.[2] EPOC's Machine Info screen names the screen "LCD", the power supply "APM 500" and the keyboard "LAP 53".[2]
The RS-232 serial link runs at up to 115,200 baud, and there is an IrDA SIR infrared port.[3]
Power
[edit | edit source]| Item | Specification |
|---|---|
| Main cells | 2 × AA alkaline |
| Backup cell | CR2032 lithium; Psion lists Duracell DL2032 and CR2032 cells from Hitachi Maxell, Panasonic, Sony, Ultralife and Varta |
| Mains adaptor | 6 V DC ±10 %, 1 A |
| Operating temperature | 0–40 °C |
Switched off, the 5mx stays in standby and uses about 1 % of the battery charge per day.[3] Typical use from a pair of AA cells is 10–20 hours.[1] Removing the main cells and the backup cell at the same time erases all the information in the machine.[3] For a soft reset, press an unfolded paper clip into the reset hole above the backup cell; for a hard reset, which erases the internal disk, do the same and then hold both Shift keys while pressing Esc.[3]
Series 5 and Series 5mx
[edit | edit source]The two look almost identical, but their main boards, screens and other internal parts are different and not interchangeable. The screen ribbon cable, the part most often replaced, is also different.[1][5]
| Machine | Differences from the 5mx |
|---|---|
| Psion Series 5 (1997) | CL-PS7110 with ARM710a core at 18.432 MHz; 4 MB or 8 MB; different main board, screen and screen ribbon |
| Psion Series 5mx Pro | Operating system loaded from a Sys$rom.bin file on CompactFlash, so it can be upgraded |
| Ericsson MC218 | A rebadged Series 5mx |
| Psion Revo and Revo Plus | Smaller, with a 480 × 160 screen, rechargeable cells, no backlight and no CompactFlash slot |
Software
[edit | edit source]The 5mx runs EPOC32, the operating system later renamed Symbian OS, with a word processor, spreadsheet, database, email, contacts, agenda and the OPL programming language.[1] The OpenPsion project (formerly PsiLinux) supports Linux on the 5mx.[1] Ash Wolf's WindEmu emulates the 5mx.[2]
Service manual and documentation
[edit | edit source]- Psion Series 5mx User Guide (PDF) – Psion's user guide for the 5mx, including care and safety, batteries, resetting and the specification.[3]
- Psion Series 5 Service Manual – Psion's service manual for the Series 5. It predates the 5mx, but the disassembly sequence and reassembly cautions are a guide to the similar 5mx case; its part numbers and electrical figures are for the Series 5.[4]
Known faults
[edit | edit source]The commonest fault is the screen ribbon cable, which cracks around a hole left from manufacture after years of opening and closing, and puts horizontal lines across the display.[5] The 5mx lid is held by spring wires hooked into the ABS case at the rear centre and at each end;[5] on old Series 5 machines, which use the same arrangement, Peter Vis found the plastic hooks brittle and broken.[6] See:
- Psion Series 5mx Troubleshooting Guide
- Psion Series 5mx General Maintenance
- Psion Series 5mx Hinge Repair
- Psion Series 5mx Capacitor Replacement Guide
Related pages
[edit | edit source]- Psion Series 5mx General Maintenance
- Psion Series 5mx Troubleshooting Guide
- Psion Series 5mx Hinge Repair
- Psion Series 5mx Capacitor Replacement Guide
- Psion Series 5
- Psion Series 5mx Pro
- Psion Revo
- Battery Refurbishment
- PsionNet
References
[edit | edit source]- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 "Psion Series 5", Wikipedia. Model history, the sliding case (EP 0766166, Martin Riddiford of Therefore Design), key pitch, battery life, the 5mx Pro and Ericsson MC218, the Executive Edition, OpenPsion, and the non-interchangeability of Series 5 and 5mx internals.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 Ash Wolf, "'16 Shades of Grey' – Building a Psion/EPOC32 Emulator", 27 December 2019. The Windermere chip and ARM710T core, the Series 5's CL-PS7110, the Etna CompactFlash controller, the PROM and its contents, the ADC channels, the hardware names reported by EPOC, keyboard scanning and the digitiser coordinates.
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 Psion Computers PLC, Series 5mx User Guide, Version 1.1, October 1999, part no. 6105-0053-01. Hosted on this wiki as File:Psion Series 5mx User Guide (October 1999).pdf. Care and safety and batteries (pp. 176–179), resetting (pp. 185–186) and specification (p. 191).
- ↑ 4.0 4.1 Psion Computers PLC, Series 5 Service Manual, November 1997. Hosted on this wiki as File:Psion Series 5 Service Manual (November 1997).pdf; see Psion Series 5 Service Manual. Circuit description (PDF pp. 6–7) and disassembly (pp. 17–25). Written for the Series 5, before the 5mx.
- ↑ 5.0 5.1 5.2 David Savery, "Psion Series 5MX disassembly and screen cable repair", R3UK, 6 July 2004. The 5mx screen ribbon failure, disassembly and the different Series 5 ribbon.
- ↑ Peter Vis, "Psion Series 5 Hinge Wire Repair", petervis.com.