MZTX-PI-EXT

!!work in progress!!

The MZTX-PI-EXT board (also known as Tontec) is an add-on board with a 2.4 inch 240x320 tft color touchscreen with extention hooks.

==Display == A user process (mztx06a) watches changes in the frame buffer and sends them through the SPI bus to the screen. The refresh rate is not intended to display video but is correct for classical GUI.

Touch
The 'touch' part is handled by a TSC2003 chip on the I2C bus and uses the J1-Pin7 (GPIO-04) for the /PenIRQ signal. Two kernel modules are required : tsc2007.ko (compatible TSC2003) and (a modified) tsc_raspi.ko. Pull-up can be setup with WiringPi's gpio(1) command.

Two/three changes are needed to the original tsc_raspi.c :
 * i2c_get_adapter(1); /* '1' in place of '0' : the I2C bus on the J1 connector is the second one */
 * gpio_request_one(tsc2007_penirq_pin, GPIOF_IN, "PENIRQ"); /* without '| GPIOF_OUT_INIT_HIGH'; the pin is 'IN' with a pull-up */
 * tsc2007_penirq_pin = 4; /* J1-Pin7 is GPIO-04; this can also be specified while insmod'ing */

To enable the driver,
 * $ sudo insmod tsc_raspi penirq_pin=4
 * $ sudo gpio mode 7 up

Extensions
The board uses the J1 'GPIO' connector but offers header pins for extensions :
 * An alternate power 5 volts connector (unprotected like the Pi's micro-USB one : 5 volts no more - no less)
 * SPI bus
 * I2C bus
 * LP3943, '16-LED Fun Light Driver'