Editing Psion Siena (section)

== Hardware ==

{| class="wikitable styled-table" style="width:100%; text-align:left;"
|+'''Psion Siena specification'''<ref name="wpsiena" /><ref name="spec" />
! Item !! Specification
|-
| '''Processor''' || NEC '''V30H''' (80C86-compatible, 16-bit) at '''7.68 MHz''' — the same as the Series 3a
|-
| '''ROM''' || 512 KB
|-
| '''RAM''' || 512 KB or 1 MB
|-
| '''Display''' || '''240 × 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 × AAA cells'''
|-
| '''Backup power''' || '''CR1620''' lithium coin cell
|-
| '''Size and weight''' || 150 × 73 × 19 mm, 183 g with batteries
|}

The screen is an unusual shape for the family: '''240 × 160''' is half the width of the [[Psion Series 3a|3a]]'s 480 × 160 but twice the height of the [[Psion Series 3|Series 3]]'s 240 × 80.<ref name="spec" />

For the underlying architecture — the SIBO power states, the supply rails and the ASIC arrangement — see [[Psion Series 3a]], which describes the same platform.<ref name="sibo">Psion PLC, ''SIBO Hardware Reference'', version 2.10, 3 February 1995, in the [https://doc.psion.info/books/the-psion-sibo-software-development-kit/page/hardware-reference Psion Documentation Project]. Source for the SIBO architecture, power states and supply rails shared across the family.</ref>