Psion Revo palm pc serial

[ChristofferB]

Hey! This is sorta the middle ground between a fix and a mod. I've gotten an old Psion Revo plus aka. Diamond Mako palm pc - 90's pda like thing. It communicates exclusively via serial, but I don't have the "cradle" docking station that has a DB9 out for RS232.

It does have a serial connector, for the cradle, which takes RS232 levels, though. Using the MAX3243.
But there's no RS232 level output on any of the pins. Soldered a db9 onto them, using this pinout:
http://igorkov.org/psion-usb.

Now, there are a couple of pins on the cradle connector that's not used - a VCC pin, and one that isn't marked in the pinout. Could be a sense pin, to enable serial functionality, which would explain why it doesn't do anything, but I don't know.

So has anyone tried to add serial to this device without the cradle? Does anyone have the full pinout for the docking cradle?

Any info or ideas would be useful, as I'm not really getting anywhere myself.

--Christoffer

[macboy]

is the MAX3243 in the PC or in the cradle? If it is in the cradle, then you will only find logic level UART signals (not RS-232 level) on the pc-to-cradle connector. In fact, connecting RS-232 level signals could kill the thing.