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Re: Palm Pilot LCD screen pinout in progress
I have a similar Palm Pilot type PDA screen - the circuit board is silkscreened with a Picvue PC1721WE legend. Purchased from excesssolutions.com
This also has a 20 pin connector, but appears to be different from the Picvue PC0919WE07 described in the Olimex page.
PC1721WE seems to have a built in EL driver with a H826 driver IC (compared to the H830 in the Olimex schematic which looks like it is external to the LCD module). PC1721WE also seems to have a built in contrast voltage supply circuit.
Playing with a multimeter, I am reasonably certain that pins 20...17 are data bus, 13 & 7 are GND, 4..1 are the touchscreen interface pins.
Pins 14,11,8 and 5 are also connected to the lcd glass traces - i assume they are control pins - clock, enable etc.
There is also a pad on the board that seems to be a testpad for the contrast voltage.
Just by supplying power 3.3V to the H830 EL driver VDD pin, and 3.3V to pin 11 and pin 14, I can see the display flash, and then a contrasty line on top, and the testpad voltage is 21.5V. When I set pin 11 to GND, the screen flashes, and then blanks, the test pad voltage is 15V. From this i assume there is no need for me to supply an external 18V VHH drive as per the PC0919WE interface in the Olimex schematic.
Any pointers to similar LCD interfaces / pinouts / datasheets would be much appreciated !! I got two of these for $5 each, would be great if I can get them up and running.
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