ext_int_edge in an ISR?

[ajt]

Is there any reason to not call ext_int_edge in an ISR? I want to do this to do x2 decoding of an encoder and want the interrupt to fire on both edges of the Phase A pulse.

Al
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This message was ported from CCS's old forum
Original Post ID: 144516165
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Al Testani

[PCM programmer]

:=Is there any reason to not call ext_int_edge in an ISR? I want to do this to do x2 decoding of an encoder and want the interrupt to fire on both edges of the Phase A pulse.
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This message was ported from CCS's old forum
Original Post ID: 144516166

[John Taylor]

I did what you're suggesting to time 4 channels of RC PPM control with the 4 port B interrupt on a PIC18F6620 and out of an hour of testing did not miss a single edge (4 independent pulses with a 15ms average period of continuously variable duty cycle). The only requirement is that your ISR (+context switching) can't make you miss any edge.

:=Is there any reason to not call ext_int_edge in an ISR? I want to do this to do x2 decoding of an encoder and want the interrupt to fire on both edges of the Phase A pulse.
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This message was ported from CCS's old forum
Original Post ID: 144516183