Quote Originally Posted by Art View Post
variable blabla = 0
was asmed to clrf statements because the last time I checked,
PBP zeros variables by copying a zero value to the variable like any other value,
wasting one instruction per "variable = 0" statement.
No, PBP will use CLRF when zeroing a variable.

That ISR is from the original Elapsed Timer Demo, in which I had declared the variables without bank assignments, letting PBP assign the banks as needed.

By changing Seconds = Seconds + 1 to incf _Seconds,F, you have bypassed PBP's banking mechanism and it's likely you are overwriting other variables in RAM.
The few bytes that were gained, were probably the instructions changing banks.

If you declare the variables as BANK0 it would be ok.
Or if you put them back to PBP statements it will be ok.