I'm a user of thinkpad X60 Tablet since 2007 and i really like the Wacom Digitizer and touchscreen!
I've got a X61t with broken screen. So I took this as a chance to upgrade my X60t with the newer mainboard...
The screen was broken but the touchscreen and the Wacom Digitizer were still working. So I peeled this stuff off and had a closer look on the hardware.
The Display unit has the IBM Partnumber: FRU 13N7205
The Wacom Type (or whatever it is) SU-1208E-01X
The resistive touchscreen is evaluated by a Gunze AHL-71N chip.
This company does not provide much information on this thing.http://www.gunzeusa.com/controller-chip-comparison-guide
But I found this chinese manufacturer: http://www.daisendenshi.com
they have a singleboard computer that uses this chip:http://www.daisendenshi.com/products_view.php?products_id=330&products_name=SH-2009&master_categories_id=137
The schematics are included in the manual:http://www.daisendenshi.com/cart/images/SH-2009/sh2009_usersguide.1.0.1.pdf
exerpt from the manual:
looked well to me because it communicates via RS232 =)
but i had a closer look on this things
the Wacom W8003 brought me to this forum, but I found no further information on this piece of BGA-shit
so I tried to find out what the third larger chip on this PCB was
it is an µPD78F0535A microcontroller
some beeps of my multimeter and 2 hours later I had understand the most connections of the wire coming from the mainboard
I don't know what this orange cable that is connected to pin 50 (analog input) is uses for.
and I was not able to follow the trace after resistor R2 & R3 because they directly and in a feedthrough
I'm going to get a MAX232 TTL-converter now to make some tests with the drivers provided by IBM/Lenovo.
Anybody out there with some further knowledge about the wacom drivers communicate with this things and how this things are connected inside an notebook/tablet pc?
regards from Germany