I have a IMX28EVK board and I would like to to connect this board to a 5-wire resistive touchscreen.
In the Reference Manual of the I.MX28, Freescale said:
LRADC 2 - 6 can be used for 4/5-wire touch-screen control. LRADC 6 can be used for the wiper of 5-wire touch-screen controller and external temperature sensing, but they cannot be enabled at the same time in hardware configuration. LRADC 5 can be used for Y- of 4-wire and LR of 5-wire; LRADC 4 can be used for X- of 4-wire and UR of 5-wire; LRADC 3 can be used for Y+ of 4-wire and LL of 5-wire; LRADC 2 can be used for X+ and UR of 5-wire; For pull-up or pull-down switch control on LRADC2~5 pins, please refer to HW_LRADC_CTRL0 register.
I think that there's an error. The word UR is repeated 2 times and UL never appears
I have this touchscreen:
Model: EL-TS-104F-5H Type: Analog resistive 5 wire B-type.
This touchscreen has 5 pin:
1 - RT; 2 - RL; 3 - SG; 4 - LT; 5 - LL |----------| |LT RT| | | |LL RL| |----------|
I've made this connection:
RT <-> UR RL <-> LR SG <-> wiper LT <-> UL (?) LL <-> LL
But the touchscreen doesn't work properly. Is the connection that I've made is correct? If not, what's the right connection? Any suggestions?