Editing Psion Organiser

{{Infobox computer
| name         = Psion Organiser
| image        = [[File:Psion Organiser Series 1.jpg|250px]]
| caption      = The Psion Organiser (Series 1) with its sliding cover removed
| developer    = Psion Processors Ltd
| manufacturer = Psion Processors Ltd
| type         = Handheld pocket computer
| release_date = 1984
| cpu          = Hitachi HD6301X 8-bit CMOS @ 0.9216 MHz (3.6864 MHz crystal)
| memory       = 2 KB RAM, 4 KB ROM internal to the CPU (14 KB total with one 8 KB Datapak)
| storage      = Two Datapak / program pack slots (EPROM, 8 KB and 16 KB paks)
| display      = 16-character single-line dot-matrix LCD
| sound        = None
| dimensions   = 142.0 mm × 78.0 mm × 29.3 mm (cover closed)
| weight       = 225 g
| os           = Psion Organiser firmware in the CPU's internal 4 KB ROM
| successor    = [[Psion Organiser II]]
| model        = Also sold as the OTG-PC and the NUME Executive Lifestyle Pocket Computer
}}
The '''Psion Organiser''' — retrospectively the '''Series 1''' — is the handheld computer Psion Processors Ltd launched in 1984, and the machine that started the whole Psion line. Psion marketed it as a pocket computer with two removable "solid-state drives", and it is widely described as the first practical electronic organiser.

It is a spartan machine by later standards: a single line of sixteen characters, 2 KB of RAM, a 4 KB firmware ROM inside the processor itself, and no operating system to speak of. Almost all of its capability comes from the removable '''Datapaks''' and program packs that plug into the two slots in the back.<ref name="p1man">''The Organiser Manual'', Psion Processors Ltd, 1984, transcribed at [https://www.jaapsch.net/psion/p1manorg.htm Jaap's Psion Organiser II Page]. Source for the technical data, power consumption, Datapak specifications, operating framework, error messages and the manufacturer's own troubleshooting section quoted throughout this page.</ref>

== Technical data ==

The following is Psion's own published specification.<ref name="p1man" />

{| class="wikitable styled-table" style="width:70%; text-align:left;"
|+'''Psion Organiser Series 1 — manufacturer's technical data'''
! Item !! Specification
|-
| '''Microprocessor''' || Hitachi '''HD6301X''' eight-bit CMOS microprocessor with a '''0.9216 MHz''' clock, derived from a '''3.6864 MHz''' crystal
|-
| '''ROM''' || 4 KB, '''internal to the microprocessor'''
|-
| '''RAM''' || 2 KB
|-
| '''EPROM''' || 8 KB in the supplied Datapak, extendable
|-
| '''Total memory''' || 14 KB with one Datapak fitted
|-
| '''Clock''' || CMOS real-time clock from a separate '''32768 Hz''' crystal
|-
| '''Display''' || Sixteen-character alphanumeric dot-matrix liquid-crystal display, one line
|-
| '''Keyboard''' || 36 keys — ON/CLEAR, MODE/HOME, FIND, SAVE, EXECUTE, SHIFT, DELETE, SPACE, &lt;&lt; and &gt;&gt;, plus A–Z with numbers, arithmetic symbols and punctuation on shift
|-
| '''Dimensions''' || 142.0 × 78.0 × 29.3 mm with the protective case closed
|-
| '''Weight''' || 225 g as sold
|-
| '''Power source''' || Any 9 V PP3 battery. '''Psion state that a mains adaptor should not be used, because it may damage the Organiser.'''
|}

=== Power consumption ===

Quoted in milliwatts at the 9 V battery input:<ref name="p1man" />

{| class="wikitable styled-table" style="width:70%; text-align:left;"
! State !! Power
|-
| Machine off || 0.2 mW
|-
| Machine on || 40.0 mW
|-
| Datapak access, one pak (during SAVE or FIND) || 500 mW
|-
| Datapak access, two paks || 800 mW
|}

The clock keeps running for about '''fifteen seconds''' after the battery is disconnected, provided the machine was switched off first — long enough to change a battery without having to reset the time. The Organiser also '''switches itself off after five minutes''' with no key pressed.<ref name="p1man" />

== Inside the machine ==

The Organiser is built as two boards joined by a ribbon and a pair of pin headers, an arrangement it passed on to the [[Psion Organiser II|Organiser II]].

=== "PSION PROCESSOR" board ===

The processor board is '''surface-mount''' and carries:<ref name="galp1">[https://www.jaapsch.net/psion/galp1.htm Psion Organiser Series 1 Image Gallery], Jaap's Psion Organiser II Page. The device markings, board silkscreen legends and construction described in this section are read from the internal photographs published there.</ref>

* '''HD6301X0F''' — the Hitachi CPU, in a flat pack, with the 4 KB firmware masked into it
* '''HD44780A00H''' — the Hitachi LCD controller, the same family part the Organiser II uses
* '''HEF4081BT''' (quad AND), '''HEF4011BT''' (quad NAND), '''HEF4013BT''' (dual D flip-flop), '''HEF4040BT''' (12-stage counter) and '''HEF4060BT''' (14-stage counter with oscillator) — discrete CMOS glue logic
* Two crystal cans, for the 3.6864 MHz processor clock and the 32768 Hz real-time clock

The reverse of the same board carries the '''gold-plated interdigitated keyboard pads''' that the conductive rubber keymat shorts, and the LCD module clamps to its edge.

That discrete-logic arrangement is the main architectural difference from the Organiser II, which replaced all of it with a single semi-custom control IC.

=== "PSION POWER" board ===

The power board is '''conventional through-hole leaded construction''' — quarter-watt resistors, TO-92 transistors and leaded electrolytics — which makes it far friendlier to work on than the Organiser II's surface-mount power board. It carries an '''LM324N''' quad op-amp at IC1, the '''VR1''' contrast thumbwheel, a reference diode marked '''RD1''', a zener marked '''ZN1''', and electrolytics at designators including C1, C3, C5, C6, C8, C9 and C10.<ref name="galp1" />

Those designators, and the LM324-plus-reference-diode arrangement, are '''the same scheme Psion documented for the Organiser II power supply board''', which suggests the two are closely related designs. Psion never published a Series 1 schematic or parts list, so the Organiser II Technical Manual's power supply chapter is the best available guide to how this board works — but the component ''values'' must be read off your own board. See the [[Psion Organiser Capacitor Replacement Guide]].

== Datapaks ==

[[File:Psion Organiser Datapak.jpg|thumb|300px|A Psion Datapak. Data is stored in EPROM, so nothing can be electrically erased — deleted records are merely marked as skipped and continue to occupy space.]]

The two slots in the back of the machine are what Psion called '''solid-state drives'''. Drive one came with a real Datapak; drive two came with a '''dummy pak''' fitted to protect the contacts, and Psion's instruction is to keep a real or dummy pak in each slot at all times.<ref name="p1man" />

For the Series 1, Datapaks came in '''8 KB and 16 KB only'''.<ref name="galp1" />

{| class="wikitable styled-table" style="width:100%; text-align:left;"
|+'''8 KB Datapak — manufacturer's specification'''<ref name="p1man" />
! Item !! Specification
|-
| Capacity || 8 KB — 10,900 characters of packed data
|-
| Storage medium || EPROM
|-
| FIND time || Worst case with a full pak, 5 seconds maximum
|-
| SAVE time || 4–8 characters per second, depending on battery age
|-
| Data retention || Mean time to failure 50 years at temperatures up to 100 °C
|-
| Formatting || 30 minutes in a Psion Formatter prepares a pak for re-use
|-
| Life || Can be formatted up to 100 times
|}

Because the storage is EPROM, '''erasing a record does not free the space''' — it is only marked so that the Organiser skips it. The only way to reclaim a pak is to erase the EPROM optically: the '''Psion Formatter''' shines ultraviolet light through the window in the chip for half an hour. The white label on the underside of a pak is there to keep light off the die, and has to be removed before formatting.<ref name="p1man" /><ref name="galp1" />

'''Program packs are different again.''' Most Series 1 software packs use a special board silkscreened "PROGRAM PAC" in which the '''programming voltage (Vpp) line is not connected''', so the pack cannot be written to even though it contains an EPROM. The Link-Up Pack and the Software Pack used ordinary Datapaks so that settings and programs could be saved onto the same pak.<ref name="galp1" />

== Using the machine ==

The Organiser has no menu system. It has a set of '''activities''', shown as an indicator to the left of the current line:<ref name="p1man" />

{| class="wikitable styled-table" style="width:100%; text-align:left;"
! Activity !! Purpose !! How it is selected
|-
| '''ENTER''' || Neutral state for typing and editing || MODE/HOME
|-
| '''SAVE''' || Write the current line to a Datapak as a record || SAVE key (press again to alternate between SAVE1: and SAVE2:)
|-
| '''FIND''' || Search a Datapak for a record || FIND key
|-
| '''CALC''' || Calculate the current line || MODE/HOME
|-
| '''OFF''' || Switch off || MODE/HOME, then EXECUTE
|-
| '''ERASE''' || Mark a retrieved record as deleted || MODE/HOME, but only while a found record is displayed
|}

Nothing happens until '''EXECUTE''' is pressed. Useful limits and behaviours:

* A line may be up to '''200 characters''' long. If typing stops having any effect, that limit has been reached.
* A search clue may be '''1 to 15 characters''', and may occur anywhere in the record. Prefixing it with an '''asterisk''' anchors it to the start of the record, so <code>*SUS</code> finds ''SUSAN SMITH'' but not ''CONSENSUS''.
* An empty search clue steps through every record in the pak.
* The calculator handles numbers of up to '''seven digits''', exponents from '''1.000000E-99 to 9.999999E99''', and '''two levels of brackets'''.
* A calculated answer is not part of the current line and cannot be saved — unless you edit it, at which point it becomes the line and can be saved like anything else.

== Error messages ==

{| class="wikitable styled-table" style="width:100%; text-align:left;"
! Message !! Meaning
|-
| '''LOW BATTERY''' || Battery voltage too low. '''Do not SAVE after seeing this''' — a failed write can spoil the remaining space in the pak.
|-
| '''DATAPAK FULL''' || The pak cannot accept the record. Remember that erased records still occupy space.
|-
| '''DATAPAK ERROR''' || The Organiser cannot access the pak. Normally means physical damage, or a write attempted after a LOW BATTERY warning. Existing records can usually still be read, so transfer them to another pak.
|-
| '''NOT FOUND''' || The search clue does not occur in that pak.
|}

== Variants ==

Two rebadged versions were produced:<ref name="galp1" />

* '''OTG-PC''' — the "On-The-Go Pocket Computer", distributed in the United States by Superior Systems Inc. The Psion logo on the cover is replaced by OTG-PC, the keyboard lettering differs slightly, and it uses <code>$</code> rather than <code>£</code>.
* '''NUME Executive Lifestyle Pocket Computer''' — a Norwegian nutritional-products company's branded machine, in blue rather than red styling, with a keyboard including the dollar sign and accented characters, intended to run diet-planning software.

== Design registration and patent ==

The Series 1 was covered by UK Registered Design applications '''1019736''' and '''1019737''' — the Organiser and the Datapak respectively — and by UK patent application '''GB 2 161 300 A''', which lapsed in 2004.<ref name="galp1" />

== General maintenance ==
{{Main|Psion Organiser General Maintenance}}

Battery leakage from the PP3, contact corrosion in the pak slots and the conductive rubber keymat are the routine concerns. See the [[Psion Organiser General Maintenance]] guide.

== Troubleshooting ==
{{Main|Psion Organiser Troubleshooting Guide}}

Psion's own manual carries a short troubleshooting section, and the closely related Organiser II Technical Manual explains the circuit well enough to take diagnosis a good deal further. See the [[Psion Organiser Troubleshooting Guide]].

== Capacitor replacement ==
{{Main|Psion Organiser Capacitor Replacement Guide}}

All the electrolytics are on the through-hole power board, which makes a recap straightforward. No values were ever published, so they have to be read from the parts. See the [[Psion Organiser Capacitor Replacement Guide]].

== See also ==

* [[Psion Organiser II]] — the 1986 successor, with a proper operating system, OPL and a top slot
* [[Battery Refurbishment]]
* [[Battery Explosion, Capacitor or Corrosion Damage]]

== References ==

<references />

{{Navbox-Psion}}

[[Category:Psion]]
[[Category:1984 Computers]]