Check if PWM is connected

[skoberlink]

I am writing code for a circuit that may or may not have a position transducer attached (this will be optional). The transducer sends a pwm signal that I read on the CCP module.

How can I tell if it's attached? The only thing I can come up with is some kind of timeout on the CCP module. If the timeout runs out, I know the PWM isn't attached and I can skip the reads from there on. I can't figure out a way to have the CCP timeout and just move on to the next instruction. I'm also open to other suggestions on checking if its attached.

This is on a PIC16F88 btw. Thanks in advance!

[jbmiller]

You could monitor the current that the transducer draws. Obviously, if the transducer is plugged in, you'll get a reading of 'I'm here', providing the transducer gets its power from the same board that the PIC is on.

Or you could have an I/O pin dedicated to a loopback in the transducer's connector to confirm the unit is plugged in.

The problem with monitoring the PWM O/P is that the transducer might be in idle, in setup, offline, broken?, etc. and not give you the reading you expect.

[skoberlink]