16F1937 8bit timer 2/4 & 6

[medelec35]

As timer 2/4 & 6 are 8 bits, they should not default to(or allow) 256 rollover value:

8 bit timer.png

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When OK is clicked on the values are excepted.

[Benj]

Hi Martin,

The rollover of 256 as the default is correct.

The interrupt occurs when the count register goes from 255 to 0 e.g. the 256th count.

0 to 1 = count 1
1 to 2 = count 2
...
254 to 255 = count 255
255 to 0 = count 256

We use the rollover value - 1 behind the scenes in the rollover register so 256 would become 255 for say the PR2 register.

[medelec35]

Hi Ben,

We use the rollover value - 1 behind the scenes in the rollover register so 256 would become 255 for say the PR2 register.

Ah I did not know that.
Thank you, that would explain it