GPIO not working
Posted: Tue Apr 20, 2010 4:09 am
Hi all,
I have a touch screen driver IC connected to the SPI bus with the PENIRQ output of the IC connected to IRQ3 input on the MOD5234 I am using.
I have used the following to setup the IO pin as a GPIO input as I only want polling at the moment. After I do this, the input never goes low and there is a waveform present when checked with a scope. I don't init the IC at this time as the power on default is to generate a LOW on PENIRQ output when the touchscreen is touched. If I reset the Netburner and don't yet run the code, I can see PENIRQ trying to go low. It is sitting at 3.36V and goes to 3.20V when I touch the screen.
J2[45].function(PINJ2_45_GPIO); // Pen touch input
I then read the input using the following
State = J2[45];
I just never get the IO line going low.
What am I missing?
Cheers,
Dave...
I have a touch screen driver IC connected to the SPI bus with the PENIRQ output of the IC connected to IRQ3 input on the MOD5234 I am using.
I have used the following to setup the IO pin as a GPIO input as I only want polling at the moment. After I do this, the input never goes low and there is a waveform present when checked with a scope. I don't init the IC at this time as the power on default is to generate a LOW on PENIRQ output when the touchscreen is touched. If I reset the Netburner and don't yet run the code, I can see PENIRQ trying to go low. It is sitting at 3.36V and goes to 3.20V when I touch the screen.
J2[45].function(PINJ2_45_GPIO); // Pen touch input
I then read the input using the following
State = J2[45];
I just never get the IO line going low.
What am I missing?
Cheers,
Dave...