Driving 4 Wire Resistive touchscreen with AVR ATMEGA128(PORTF Problem)

[nimra]

hi all
because of 4Kb ram, 7 I/O ports and reasonable price of ATMEGA128 i've selected it
after creating smd to dip adapter and programming the MCU i faced a problem that i changed M103C fusebit,however problem solved but i found that PORTF cannot act as I/O
i read many topics in this forum about this issue but none of them gotten a logical result
i want to driving four wire resistive touch panel,this type of touchscreens needs two output pin and two input pin(reading ADC0 for coordinating x or y at a moment
unfortunately ADC pins are placed on PORTF
how can i use two pins of PORTF as output and two of them as input for reading adc???
my compiler is codevision 2.5.0
regard

 

[alexan_e]

I assume you have disabled the M103C compatibility mode so it it not a problem.
Have you disabled the JTAGEN fuse?

 

[nimra]

thanks guy
yeah:-D
i had disbled jtag and m103 fusebits before
atmega128 has two sets of vcc and gnd pins,because of connecting only one set of them MCU was not working quite right (all the ports worked fine except F and G)
everyone please note that to connect both of them otherwise you will face some problems like this