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Psion Siena

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Psion Siena
A Psion Siena, open
Specifications
DeveloperPsion PLC
ManufacturerPsion PLC
TypePocket organiser / PDA
Released1996
CPUNEC V30H (80C86-compatible) @ 7.68 MHz
Memory512 KB ROM; 512 KB or 1 MB RAM
StorageNo internal SSD bay โ€” external SSD or PC-Card drive via the serial port
Display240 ร— 160 monochrome LCD
SoundPiezoelectric beeper
Dimensions150 mm ร— 73 mm ร— 19 mm
Weight183 g including batteries
OS / FirmwareEPOC16 (SIBO), with OPL
PredecessorPsion Series 3
SuccessorPsion Revo
Model no.512 KB and 1 MB versions

The Psion Siena of 1996 is the small, cheap member of the SIBO family: the same 16-bit architecture and the same operating system as the Series 3a, in a case a third smaller and lighter, with a numeric keypad beside the screen.[1]

It is binary compatible with the Series 3, but the smaller screen and smaller memory mean many Series 3 programs had to be modified to run on it.[1]

What the Siena is not

Three omissions define the machine, and all three are regularly mistaken for faults:

Deliberate omissions[1][2]
Omission Detail
No internal SSD bays The Series 3 machines have two. The Siena has none โ€” an external SSD or PC-Card drive connects via the RS-232 serial port instead.
No external power socket There is nowhere to plug a mains adapter in. The Siena runs from its AAA cells and nothing else.
No sound recording A piezoelectric beeper only, where the 3a and 3c have a microphone, speaker and 12-bit recording.

Hardware

Psion Siena specification[1][2]
Item Specification
Processor NEC V30H (80C86-compatible, 16-bit) at 7.68 MHz โ€” the same as the Series 3a
ROM 512 KB
RAM 512 KB or 1 MB
Display 240 ร— 160 monochrome LCD. No backlight.
Keyboard 48-key QWERTY plus 8 reprogrammable application buttons, and a separate numeric keypad beside the screen
Sound Piezoelectric beeper
Communications RS-232C at 19,200 bit/s, plus infrared next to the serial port
Main power 2 ร— AAA cells
Backup power CR1620 lithium coin cell
Size and weight 150 ร— 73 ร— 19 mm, 183 g with batteries

The screen is an unusual shape for the family: 240 ร— 160 is half the width of the 3a's 480 ร— 160 but twice the height of the Series 3's 240 ร— 80.[2]

For the underlying architecture โ€” the SIBO power states, the supply rails and the ASIC arrangement โ€” see Psion Series 3a, which describes the same platform.[3]

The serial port is the whole expansion story

Because there are no internal bays, the serial port carries everything: PC connectivity through PsiWin, the external SSD or PC-Card drive, and dial-up through the Travel Modem accessory.[1]

The connector is the same as the 3c's, not the Series 3 or 3a's.[4]

The practical consequence for a collector: a Siena without its serial cable and external drive is a machine you cannot get data on or off. Source the accessories with the machine if you can.

General maintenance

Troubleshooting

See also

References

  1. โ†‘ 1.0 1.1 1.2 1.3 1.4 "Psion Siena", Wikipedia. Source for the release date, memory versions, battery arrangement, the absence of an external power socket and of internal SSD bays, the external drive option, the screen size, the numeric keypad, the processor and the binary compatibility note.
  2. โ†‘ 2.0 2.1 2.2 "Psion specifications", netogram.com. Source for the Siena's dimensions, weight, ROM and RAM sizes, screen resolution, keyboard layout, sound hardware, serial speed and expansion arrangement.
  3. โ†‘ Psion PLC, SIBO Hardware Reference, version 2.10, 3 February 1995, in the Psion Documentation Project. Source for the SIBO architecture, power states and supply rails shared across the family.
  4. โ†‘ "Psion Series 3", Wikipedia. Source for the statement that the 3c's serial port was changed to match the Siena's.