Oh..Thanks Sir Darrel Taylor.

working fine now. but how i show "-" sign for tension measurements.

One thing more , just for information.

my encoder is 1000 PPR
CHIP 18F4550
XTAL mount 20 mhz
Code:
__CONFIG    _CONFIG1H, _FOSC_HSPLL_HS_1H
DEFINE OSC 20
I lose the count in > 5 RPM with above code.

And if mount XTAL 20 mhz
and if i code
Code:
__CONFIG    _CONFIG1H, _FOSC_HSPLL_HS_1H
DEFINE OSC 3
this is work up to 20 RPM. No counts lose.
Is DEFINE OSC 3 will increase the speed of PIC ?

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