Page 1 of 1

Is 40MHz PIC18F2685 of IFC fast enough to detect encoder

PostPosted: Wed Dec 07, 2011 2:12 pm
by limbq
Hi,

i am using IFC main brain card which having PIC18F2685 with 40MHz clock.
I am thinking to use the PIC interrupt of INT0 and INT1 to detect the pulses (channel A and channel B) from a DC motor encoder (IG32E-100K),
the IG32E-100K with 700 pulse per rotation may give me around 0.5deg resolution per pulse.
The encoder signal will be directly connect to RB0 and RB1 pin of PIC, with pull ups from Dual Brush Motor card.

But i having concern if this high resolution pulses will react too fast for the PIC interrupt to react?
I am using that IG32E-100K as position encoder.
can i maintain to use this or should i use lower pulse count per rotation one?

pls advise and thanks.

Re: Is 40MHz PIC18F2685 of IFC fast enough to detect encoder

PostPosted: Wed Dec 07, 2011 8:20 pm
by robosang
It will depends on how fast the motor is rotating, so you will get the frequency of the pulses from the encoder. also how short your ISR will also affect the performance. :D

Re: Is 40MHz PIC18F2685 of IFC fast enough to detect encoder

PostPosted: Wed Dec 07, 2011 11:50 pm
by limbq
Thanks Robosang,
I actually use it as a tensioner only, thus think it shouldnt turn too fast, think the interrupt should be able to react fast enough la, hopefully :D