Someone asked me about connecting the P900/P910 to some standard RS232 device (for example, a Cisco router with a serial port, or connecting to an Unix system in place of a serial terminal).
The P800/P900/P910 phones do not have a true "serial" port.
Their cradles actually contains an "USB serial" converter, which needs USB hardware to be connected, and need a software driver for interpreting the in/out "packets" as serial stuff. This is why they can use high speeds (more than 115k2). Current versions of Linux and Windows have native "USB serial" support drivers, so that the usage "phone to computer" is transparent (it actually seems a serial port).
With some little effort (as shown in the p3nfs sources) one can use the Symbian operating system functions to create some transparent usage (serial-like: "send a character, read -if available- a character"). But these are "software" methods, it's not a true serial port that you can drive from a phone installed software.
Back in the old days, lots of organisers had full RS232 ports (and they were used to install software on them).
Back in the very beginning of the 1990, I transferred 130kb of C source (a text adventure game) from my Psion Organiser LZ64 to an Ultrix machine directly on the serial port (my tiny OPL program placed a login on an Annex, made a few cat >filename.c Unix commands, and gently closed the session). A few weeks after, there was the big hype of the MUDs at the University of Salerno (thanks to me, the Hero of the C Source) :-)
So we could try to buy some bluetooth rs232 serial adapter or infrared rs232 serial dongle. I would prefer a bluetooth serial adapter because it doesn't need to be on line of sight at the infrared beam.
Any Bluetooth to RS232 adapter will be of great utility letting you to drive a true serial port - but it will cost to you some "Epoc C++" effort.
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