Psion Epoc Communication Notes

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Communicating with other computers, printers, from Psion via serial and infra red ports.

A summary of sources of information, for those who don't choose to use Windows 95, and the excellent PsiWin file transfer and conversion application that comes with the Psion 5 for cable transfer.


My first suggestion is, if you have a Windows 9x machine, upgrade your copy of PsiWin. 2.1 could be downloaded from site (about 13 disks full), or obtained on CD with the Palmtop magazine CD Rom. The even more capable 2.3 can be downloaded from Psion (2.2 is reputed to be buggy). This should solve most of your Windows 9x - Psion file transfer problems.

Please note that PsiWin does not support IrDA file transfer. If you want to use the IrDA ports, use Windows 98SE or Windows 95 with IR upgrade (do not attempt to use Windows 2000 or Windows ME - they won't work). Use PsiWin 2.1, with the service pack patches (do not use a later version of PsiWin such as 2.3, but go to 2.3.3). This method only works because IrCOMM supports imitation of an RS232 port, and is an unsupported side effect.

If you don't want to run Windows 9x all the time, but have a copy and have the disk space, try dual or multiple booting. You can do it from Linux, or Windows NT, or manually from Windows 9x, or use a boot manager like System Commander.

Psion 5 via Infrared to IBM ThinkPad under Windows 95

These hints posted anonymously on 2 April 1998.

Get updated Win95 infrared drivers from Microsoft (no URL given). Enable infrared on laptop as a com: port (usually done from Control panel, Add New Hardware). Disable the real COM: port and enable infrared communication via the freed up COM: port. Set maximum baud rate to 57.6kbs (I suspect a non-existent COM: port like #3 or #4 will work). In PsiWin, set connection to infrared and baud rate to 57.6kbs. You should hear a noise indicating a connection. Double click Control Panel, Infrared to see if Win 95 thinks it is communicating.

Opera Web Browser

The Epoc version of the Opera for Windows browser has been available since mid 2000. Psion started to ship version 3.62 with their Revo Plus models. You could purchase Opera for Epoc ER5 from for around US$30. There is also a version for ER3, however this can not use Java, and there may not be sufficient space to run it on an 8 MB Psion.

The Epoc version of Opera 3.62 has colour, frames, zooming, encryption, SSL 2 and 3 for banking, TLS, supports HTML 3.2, Javascript 1.0, cookies (which you can turn on or off) and CSS1 (but not CSS2). Internet protocols include HTTP1.0, HTTPS, and FTP, Gopher, Wais applications. It supports Java if you install the free (but memory hungry) Epoc Java Runtime Environment. It does not include the Email or News readers, nor does it print. The bookmark manager only allows add and delete (export Web bookmarks as HTML and use that as a home page instead).

Web pages that don't have height and width attributes are slow to load, as Opera has to calculate positions. This is worse with nested elements such as in tables.

There were two porting efforts, with the released 3.62 version using the Windows code, and having a bunch of around 260 Windows API functions rewritten for Epoc. There were no commercial Windows libraries for Epoc. The resulting API emulator contained 15,000 lines of code. Opera makes use of global variables, however an Epoc DLL can not have writeable statics (because it might be in ROM) and instead uses a thread local store, allocated sufficient memory for all global variables. The Opera port also uses platform independent code to display pages, as the Epoc equivalents were designed for word processing, not CSS display.

Opera now have a version 5 release, and also working on a web browser engine. This could be used independent of the user interface, and might be called by other applications.

Check either the Opera web site, or the excellent browser FAQ at

Psion InfraRed Communications Software

Jim Pollock's site had a nice range for Psion 3c, Siena and Series 5. Irbackup and Irestore backup from 3c and Siena to PC. Adds two 5k OPA files to Psion (the zipped files are 35k). Pdir is used with IrCopy and shows your Psion files on PC display. IrCopy copies between PC and 3c or Siena. Uses irNFS server on Psion. IrSave runs under DOS on your PC, and lets the PC mimic Psion IR protocol. Psion 3c or Siena think PC is another Psion. IrSend supports Psion 5, 3c and Siena, runs on PC only, detects which Psion is beaming. Jim also lists a couple of simple OPL programs for 3c and Siena so you can start experimenting with IR. IrDumpr dumps raw IR bytes to display. IrDump dumps IrDA frames to display.

Unix, PPP and Slirp

Connecting a Series 5 to a Unix box, for internet access. Reports of success and failures with Linux pppd, often due to incorrect MAC addresses coming back. CMILES at CONNECT.COM.AU Chris Miles posted about in in comp.sys.psion.comm, and Phil Whiles wrote it up in his web page. Basically download Slirp, compile it on Unix, put it in your local bin, connect your Psion via serial cable and the Comms application, login and get a Unix prompt. Run "slirp -b baudrate ppp" and see if you get a status message from slirp. Exit Comms, and start Email or Web. Your Psion modem settings are no init string, 115200 baud (if your Unix will handle it), serial, hardware flow control (RTS/CTS), default options. the Network settings are direct connection, default account, IP address and DNS you supply, login default settings.


S5FTP is an FTP client for Epoc32 computers. Serge Shestopalov In May 2000 there were two new FTP clients available for Psion 5.

Comms as a diagnostic tool

To check an IR connection, use Comms in your Psion 5 (sorry, not included in Revo). Disable serial link. Line up the IrDA ports, up to 30 cm apart. Start phone IR comms. Start Psion Comms. Set Comms to use IR port. Enter AT and see if phone responds with OK. Enter ATZ to set phone or modem to factory settings. Enter the phone initialisation string (should be provided by phone vendor, and be something like AT&FV1EO&D2&S0&C1S0=0 - this is for Nokia 7110e - do not enter a string if you don't understand what it is trying to do). Enter ATDT number to dial a number. If you dial your ISP, you can track what happens as their end responds. The ISP modem should respond and connect at 9600. You might want to turn on session logging and capture the details of what goes wrong. Even if you don't understand it, someone else may be able to help explain it.)

Psion 5 Modem Cables

The PsiWin cable with your Psion 5 (3c) is a null modem cable, so you need a null modem converter to convert it to a "straight through" cable for a modem. If your modem has a 25 pin connector, modify a 9 pin to 25 pin adaptor.

Here is a 9 pin to 25 pin adaptor, as supplied,

Signal                  9pin   25pin (Psion Honda)
Carrier Detect          1       8
Receive Data            2       3       4
Transmit Data           3       2       8
Data Terminal Ready     4      20       5
System Ground           5       7      15
Data Set Ready          6       6       3
Request to Send         7       4       7
Clear to Send           8       5       2
Ring Indicator          9      22       6

Your standard 25 pin null adaptor wires pin 7 straight through, swaps 2 and 3, 4 and 5, 6 and 20.

So here is the 9 pin to 25 pin null modem adaptor.

Signal                  9pinM  25pinM   Cross wiring on 9 pin connector
Carrier Detect          1*      8       (Pin 1 sometimes linked to 6)
Receive Data            2  in  2
Transmit Data           3  out  3
Data Terminal Ready     4  out  6*      (Pin 6 sometimes linked to 8)
System Ground           5  --  7
Data Set Ready          6* in 20       (Pin 6 sometimes linked to 1)
Request to Send         7  out  5
Clear to Send           8  in  4
Ring Indicator          9      22       (Psion connect 9 RI to 8 DCD)

I think Psion are wrong in not connecting their Pin 1 (on 9 pin D connector) Carrier Detect to the modem. Go to the Psion Control panel, select Modems, switch to Advanced Tab and Disable Carrier Detect (DCD).

Otto Sykora in Switzerland lists his home made 9 pin Null Modem cable, intended for the Revo.

9-1 (not essential)

I couldn't find a 9 pin null modem adaptor, so I looked for a DB9 Male to DB9 Male gender changer adaptor, with a removeable cover (most have one piece covers). Tandy (Radio Shack) had their 260-0280 model with clip together sides. So I just rewired it.

Justin Buckland had a site with lots of Psion connectors listed at Phil Whiles had a list of what Psion told him about cables at

Psion once had a list of how the connectors should be made on an FAQ at

Free ISPs Overseas

In the USA, we have had success with In the UK we have been advised to try FreeUK (ClaraNet) Remember that companies offering free anything go in and out of business all the time, so check before you travel.

This site will look much better in a browser that supports W3C web standards but it is accessible to any browser or internet device, including Psion Web and similar PDA or limited browsers. Netscape 4.x users - turn Style Sheets off. Your style sheet support is too broken to use (sorry). -> epoc -> communications -> epoc-comms

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