So What Is EPOC?

The marketing jargon will tell you that EPOC is a 32-bit, multi-threading operating system optimised for mobile devices with a high usage of wireless communications. But in practical terms what does that mean?

For The User

The current range of EPOC devices are all palmtop PC's produced by Psion and Oregon Scientific using the EIKON (Crystal) GUI. In addition, Ericsson markets the MC218 which is a badged version of the Psion 5mx but with a unique set of applications. Shortly, Ericsson will be launching the R380 - a mobile phone communicator-style device based on the Quartz Pearl DFRD. Many more devices are expected tofollow.

 
The Ericsson MC218

The standard range of applications varies from device to device but can include:

• Office productivity applications, rich text word processor, spreadsheet, single table database data application, all with embedding capability and a bit map drawing application,
• PIMs, vCard compatible contacts database, vCalendar compatible calendar and to do list manager
• Mobile Communications, terminal emulator, fax, e-mail and internet browser
• Miscellaneous applications including calculator, spelling checker and thesaurus, voice recording
• PC connectivity
• Development tools, OPL development environment and Java runtime, and
• (lets not forget) Games!

These applications are supported by menus, toolbars and hardware keys to facilitate access to the main applications (along the bottom of the screen) and menu access, cut and paste, infrared data exchange, zooming (on the left of the screen).

 
The EIKON GUI

Generally the applications are comparable to those found on Windows CE and in several cases are arguably richer in features. (A comparison can be found at www.foxpop.ndirect.co.uk/wince/appscover.htm.)

The compact nature of EPOC is also mirrored in the current hardware. Another key user feature is device size and weight. The Psion 5mx is 30% lighter and almost half the volume of a comparable Windows CE machine (HP 690). The Psion Revo, complete with keyboard, weighs in 25% lighter than some Windows Pocket PC devices (HP 540). This allows these machines to be comfortably carried in a suit pocket.

 
The Psion Revo

For The Developer

As mentioned earlier, EPOC is a three-tier system consisting of a Base, Middleware and EIKON GUI. This provides the ability to port to different hardware without altering the Middleware services on which all applications are built. Similarly, as DFRDs are specified, EIKON will be supplemented with additional GUIs. When developing in C++, applications should be developed as an engine and GUI to facilitate efficient adaptation to the DFRDs GUIs. (It is unclear at this stage how OPL will implement the DFRD GUIs.)

The fundamental services provided by the Middleware include:

• Stream Store
• Relational Database management system
• Text views and content (rich text editor and grid layout)
• Windows server
• Embedded Objects
• Fonts, Bitmaps and printing.

In parallel are the communications services, including Serial Sockets, Dialup Networking / TCP/IP, Telephony, fax and Infrared.

 
Symbian EPOC Architecture