PORTD and PORTE difference in ATMEGA128?

Hello,
I have connected a switch to the PD0/INT0 through 74HC14 and another
switch to the PE4/INT4 through 74HC14.
PD0 pin works fine.
But PE4 doesn't recognize the switch.
I have checked the voltage between 74HC14 output and PE4 input.
The voltage is not 5V but 1V when I push the switch.
(PD0 shows normal 5V)
When I disconnect the jumper line between 74HC14 and PE4 and then
74HC14 voltage is normal 5V.

I have set PORTE value to 0x00 and 0xFF, but the result is same.
Where am I wrong?
(Is there anything to check on fuse bit?)

QH Hong.

qhhong scrobe on the papyrus:

> Hello,
> I have connected a switch to the PD0/INT0 through 74HC14 and another
> switch to the PE4/INT4 through 74HC14.
> PD0 pin works fine.
> But PE4 doesn't recognize the switch.
> I have checked the voltage between 74HC14 output and PE4 input.
> The voltage is not 5V but 1V when I push the switch.
> (PD0 shows normal 5V)
> When I disconnect the jumper line between 74HC14 and PE4 and then
> 74HC14 voltage is normal 5V.
> 
> I have set PORTE value to 0x00 and 0xFF, but the result is same.
> Where am I wrong?
> (Is there anything to check on fuse bit?)
> 
> QH Hong.

Several things to check.

1. DDRE is set to xxx0xxxx, so that PE4 is an input.

2. You are reading PINE register and not PORTE.

3. TCCR3A is set to xx00xxxx, so that OCR3B is disconnected from the
port pin.

HTH. 

-- 
John B

Great!
Setting TCCR3A bit setting solved the problem!

Thank you very much!!

QH Hong.