Capacitive Touch Button by using ADC channel (the CVD system)

[HankMcSpank]

I wish the 'edit' period was open for a little longer here (hint!), I've just noticed an error in that last part (cut/pastes are a hack from a much larger program)

Timer0_Int:
@ INT_DISABLE  TMR0_INT   ' stop timer0 interrupts while we're in here
CPS0_PRESENTCOUNT = TMR0     ' take a snapshot of Timer0's present count.
CPS0_THRESHOLD = CPS0_LASTCOUNT - ((CPS0_LASTCOUNT/100)*2)   ' this sets the 'trigger' up for a 20% diversion (finger press)
CPS0_LASTCOUNT = CPS0_PRESENTCOUNT ' store away the present timer0count for the next time we come into the interrupt routine
if CPS0_PRESENTCOUNT <  CPS0_THRESHOLD then 'if the present incoming timer0 count is 20% below the last count, then a finger is on the sensor,go do 'stuff'
'your stuff goes here'
endif
 
 
TMR0 = 0 ' clear timer0 down
@ INT_ENABLE  TMR0_INT  ' re-enable interrupt
@ INT_RETURN

One thing to point out, depending on how reactive you want the 'sensor touch' to be trapped, you may need quite a high interrupt rate, which can bring the PIC to it's knees using the interrupt method above - not a problem if your PIC isn't doing much else, but really hampers things if it's a busy little thing!

Edit: Damn my speed typing, re this entry...

T1CON = %11000001 'enable timer 1 (bit 0) & source the clock from the CPS module (bit 6 & 7 =11

remove the above entry in my explanation post above - it relates to timer1! (which I was using too, but not needed in my example above, since I was using timer0)