All Psion machines are based around the "SIBO architecture", which was developed to meet common goals which span the SIBO range, including Series 3.
Of paramount importance is low power usage. To this end CMOS circuits are used, the CPUs are static - meaning their clocks can be slowed down or stopped and restarted without impairing function, and the specially designed ASIC chips implement sophisticated power management, which always ensures that only those parts of the machine which are needed, are powered up. Power is provided by 2 AA batteries during normal operation. A Lithium backup battery, a CR1620, is provided which maintains memory during battery changes. A mains adaptor inlet is provided.
A system clock runs independently of the CPU even when the machine is "off". This allows it to keep time and to wake the machine up when (for example) alarms expire.
A six-pin outlet is provided, through which serial and parallel ports may be connected. This outlet has exactly the same signals as the two expansion ports (SSDs).
A sound system implements beeps on the Series 3 through a low power piezo-electric element at two volumes. On the 3a there is a more sophisticated system employing bi-directional digital-to-analogue conversion, a conventional speaker, and a microphone, which together support the recording and playback of digitally-recorded sound. Digital sound data is compressed and expanded between 8 and 13 bits by hardware in an ASIC using the Alaw algorithm during recording and playback respectively, at a sample rate of 8KHz. This performance conforms to the ISDN standard for digital phone systems. A Series 3 buzzer emulation is also available on the 3a.
For both machines, there are two expansion ports, also called SSD drives, into which RAM or EPROM memory modules may be placed.
The memory is split into two types: process and storage. Storage memory is only used for storing data. Process memory is the memory used by the processor. Programs run in this type of memory. Process memory is limited on all Psions to 512k maximum. There is no storage memory on Psions with 512k RAM or less. To be honest, this is a not a big problem, since the Psion implements a real good memory management and "windows" the memory needed for each application. In practice, this means that you can open several huge databases for example and only need 10k of memory for each one.
In tabular form, the differences are summarised below:
Item Series 3 Series 3a
HARDWARE
PROCESSOR
name V30H (80C86 compatible) V30H(80C86 compatible)
Bitwidth 16 16
Speed 3.84 MHz 7.68 MHz
video mem access 8 bit - half speed 16 bit - full speed
DISPLAY
Type Monochrome LCD Monochrome LCD
Physical size 126 x 45 mm approx
Display size 240x80 480x160
Display depth 2 - black/white 3 - black/grey/white
MEMORY
Internal 128 or 256Kbyte 256Kb,512Kb,1Mb,2Mb
Expansion 2 slots = 16Meg max 2 slots = 16 Meg max
DIMENSIONS
Size 16.5 x 8.5 x 2.2 cm (6.5" x 3.3" x 0.9")
Weight 275 grams including batteries
SOUND
Output device Piezo beeper Loudspeaker
Capability variable pitched Beeps Any sound
and DTMF [*]
Digital system NONE DAC/ADC 8/13 bits
Sound recording NONE 8K samples per second
Telephone dialler DTMF capability DTMF capability
*Further sounds can be generated if a custom device driver is written
PARALLEL PORT Via optional link Via optional link
SERIAL PORT Via optional link Via optional link
Software Installed in link pod In Psion 3a ROM
Max speed 9600 baud 19200 baud
SOFTWARE
SYSTEM SHELL Controls applications Upgraded on Series 3a
DATA Database application Upgraded on Series 3a
WORD Comprehensive document Upgraded on Series 3a
processing system
AGENDA Personal management Major upgrades on 3a
application
TIME Clock and alarms manager Upgraded on Series 3a
WORLD World info database Cosmetic upgrade on 3a
CALC Calculator Calculator
Allowing OPL extension Cosmetic upgrade on 3a
SHEET [*] Spreadsheet application Speadsheet application
available as add-on [*] built-in
*In the US, and latterly in the UK, the "Series 3s" includes the
spreadsheet as standard (not for 128k models)
SPELL CHECKER/THESAURUS add-on Only on 1/2Mb models *
PATIENCE GAME add-on Only on 1/2Mb models *
*Spell checker/thesaurus and patience game are apparently not
available on all country specific 1/2Mb models (ie: not available
for french nor german models!)
OPL Programming application Series 3 compatibility
mode also available.
Normal power is provided by two AA (also known as LR6) batteries. Standby power is provided by a small Lithium backup battery, a CR1620, which maintains system data during main battery changes or failure.
It all actually depends on what type of batteries you use. Here are the advantages and disadvantages of the different battery types:
The link causes high battery loadings, as does the sound system. Accessing the SSDs also increases power drain. Because of the static architecture, a busy CPU drains more power than a sleeping one, so compute-intensive tasks will burn power. For these reasons, it is difficult to quote battery performance exactly, but the table below summarises reports received on the net.
Alkaline NiCad Lithium Running time (Hrs) 40-100 20 65-100 Power delivered (mAh) 1500 800 1600-2700 Price each (UKP) 0.5 4.5 Comment 30% lighter
The backup battery typically lasts 15 months.
It has been reported difficult to obtain these in the UK, so here is a small list to get you started. You should first check your local watch shop, since this is essentially a watch battery.
Sangers photographic, Birmingham 0121-523-4471 C.D. Zelley Ltd, Thetford 01842-755303 Apollo watch products, Tonypandy 01443-432474 Swains International, Hunstanton 01485-533393 Newey & Eyre Ltd, branches throughout the UK Watchmaker supply, Oxford 01993-842442
Yes, the Psion comes with a standard power outlet so you can use either the official Psion power supply or a general-purpose mains adaptor (which is cheaper). Negative polarity should be selected - ie the tip should be negative. The power supply should be able to deliver 150mA at 9V. The Psion adaptor has an indentation around the outer conductor near the tip which facilitates snug fit for improved reliability.
You can plug the external power supply in/out while the Psion is on. It will then immediately use the external power or batteries. The Psion also has an automatic turn off possibility. This is very useful if you often forget to turn it off! One of the choices for this auto turn off feature is "If no external power", so you can safely use it on external power and it will not turn itself off anymore until you unplug it again.
Flash SSDs are cheaper than RAM SSDs because the filesystem doesn't actually allow you to recover deleted space on them. Even if they're cheap compared to real RAMs, they're still quite expensive because they're not manufactered on a big scale (they're Psion proprietary). This tempted several people to accomplish upgrades. It has been successfully done, but I decided not to describe it here for several reasons:
The big question when the 1/2Mb models came out: can I upgrade my 512k to a 2Mb model? Well, sorry, but the answer is no. The new models use a new ROM to access the extra memory. Psion PLC does not offer upgrades for new models either. The best solution is to sell your old model and get a more recent one.
But, if you own a 128/256k or 1Mb model, upgrading it is just a matter of adding more RAM to it. Psion PLC can do this for you, contact them about it.
For the time being, process memory is limited to 512k on every model and you cannot add more whatever you do.
A lot of people buy their Psions in the UK because of the huge price difference compared to their own country. This is not a problem in itself if you just remember that you will be getting the UK version, thus the UK keyboard, applications and manual. This also the reason why so many people would like to change the keys of their keyboards. For these people, there is no simple solution. The keyboard map is not just a file held in RAM, so basically, you're stuck with your keyboard, but there are workarounds to this:
Yes, if you have Tom Dolbilin's Macro System installed, there is a macro called "BigKeys" which actually reads the serial port and sends the key to the HWIM application you're currently running. Unfortunately, it will not work with normal OPL applications. On the other hand, you will still need another computer to send the keys over the serial line, so it really isn't what people are looking for!
Keith Baker has made a little interface for just a normal keyboard (without the need for another computer) connected to the Psion using the 3-Link interface. Note that it will not work with OPL applications either.
Unfortunately you can't. The reason being that there is not only hardware but also software in the 3-Link. The 3-Link is not just a level converter, so a MAX232 or the like would not work! The extension port uses a high speed proprietary protocol (undocumented).
The "soap on a rope" is simply another name for the 3-Link. It is named like that because of it's ressemble with (guess what ;-) the well known soap on a rope.
There are a number of ways you can print from your Psion
Yes you can without fear. Nowadays the airport's X-Ray machines are harmless to palmtop computers and diskettes (hopefully ;-). In any case, if you're really not assured, ask to pass it seperately.
Yes it can! Be careful with the underside of your Psion because it is actually the speaker which contains a magnet whom is responsible for such problems. Credit cards and other magnetic data seem to be the easiest "victims" of the magnet. Check out the first page of your User Guide for Psion's own warning about this. You can try the paperclip test which consists of taking a pile of paperclips and placing the Psion on top of it. Lifting the Psion will typically take 5 paperclips with it!