3037 with a prescaler of 1:8, sets Timer1 to 500mS periods.
2 of those periods are counted to reach 1 second.

To calculate the number for any other time period, download mister-e's calculator ...

PicMultiCalc v1.3.1
http://www.picbasic.co.uk/forum/atta...achmentid=2957

In the "Timer Helper" app, set the time to 300ms and it shows the reload value as 28037. Two 300ms periods would give you a total time of 600ms.

Set it to 500mS and you'll see where I got the original number.

Any other period can be calculated easily.
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