One of the great things about the Psion computers is how easily they can be programmed.
This can be done on the Psion machine itself (using the built-in OPL editor) or by using a PC-based software development kit (SDK), software development environment (SDE) or Psion 'emulator'.
Check out the SIBO Emulators page for details about the Psion Series 3, Series 3a, Siena and WorkAbout emulators. These run the SIBO O/S under an MS-DOS environment (not a Windows Shell to DOS) and allow you to test, run or develop SIBO software.
There is a neat trick that increases the screen size of the emulator to 480 x 640 pixels, which allows you to see more lines of code in the OPL Editor.
Go to the SIBO Emulators page.
What is OPL?
OPL is a BASIC-like language which is fairly simple to learn. It is a structured, not object-oriented, language. OPL stands for Organiser Programming Language.
The term 'OPL16' is used to denote the version of OPL for the SIBO (16-bit) Psion machines. The term 'OPL32' is used to denote the EPOC/Symbian 32-bit version of the OPL programming language. Much of the OPL language is the same for both OPL16 and OPL32. Leigh Edwards describes the differences in his book "Programming Psion Computers".
Types of OPL
Psion produces two type of machines:
There are currently at least 5 variants of the OPL language:
One advantage of programming in OPL is that you can take your programming with you, on your Psion machine; you are not tied to developing on a PC. Adrian Collister, for example, programmed his Mah Jong for EPOC application entirely on a Psion handheld.
How do I learn OPL?
The OPL manual, downloadable below, is an excellent starting place to learn OPL. I thoroughly recommend that you download the PDF version and print it, if you are able, and keep it on hand as a book resource.
Programming Psion Computers
Another excellent resource for the OPL programmer is Leigh Edwards' book "Programming Psion Computers".
This is now available as a free download (2.8 MB, PDF) from EMCC's website .
OPL Manual downloads
The OPL Manual is available for free download in a number of formats (all downloads are zipped):
OPL Manual by chapter
The OPL Manual from Psion is also available in PDF format arranged by chapter. This version is dated 1997 and covers programming the Siena, Series 3 and Series 5 machines, though no doubt much will also apply to the Workabout, Revo, Series 7 and NetPad.
View: You will require Adobe Acrobat (Reader) 4.0+, or the newer Adobe Reader (which is free) installed in order to view these files in your browser, and indeed on your computer!
Download: The whole manual can be downloaded as one zipped file (see above).
Clicking each link, below, will open the file in your browser if you have an Acrobat plug-in.
To simply download each chapter, right-click a link below and select "Save Target As..." to download them without opening them in your browser.
OPL Manual on-line
The OPL Manual is no longer available on-line (in HTML format)
There are a number of great resources online, as well as the OPL Manuals (above) and Edward Leigh's "Programming Psion Computers" book, which will give you an in-depth look at programming in OPL16.
Development Kits and Environments
SIBO OPL SDK
This comprises two A4 folders, the Psion OPL software environment, and ODE (a Windows-based OPL Development Environment).
This Software Development Kit costs £120 and possibly may still be available from John Hill Computer Services Ltd. on 01226 206575, or e-mail firstname.lastname@example.org.
SIBO OPL ODE
The OPL Development Environment (a Windows-based OPL application)
can also be obtained separately.
The SIBO Emulators are useful tools for writing OPL applications. They only run under MS-DOS (not a Windows Shell to DOS) and with a cunning tweak the display can be increased to 480 x 640 pixels. The PC keyboard is obviously easier to type on than the smaller Psion one.
OPL CODE STUDIO
OPL Code Studio (497KB Zip) is aWindows-based text editor that allows you to also compile code to APP or OPO format.
OPLEditor is a programming editor for the OPL16 / 32 language, that allows you to edit, transfer and translate an OPL program in a standard PC and transfer it directly to a SIBO (Siena, Series 3) or EPOC (Revo, Series 5) device.