Updating microchip information
I'm already thinking that I will pull this out of the ISR and poll it instead.
We could certainly live with a reading on the order of 2 or 3 times per minute (very low priority as priorities go), so polling might be the way to go and leave my ISRs to do the more important stuff (like comm stuff). in fact this is the first time I've ever messed with CCP on a PIC, so forgive me if I'm going astray here. is that really the only way to measure the duty cycle?
So you headed to your vet and had the simple procedure done — your dog was in and out in minutes, and you had peace of mind. When to update This one is actually pretty simple and straightforward, and half of the answer has already been covered.
Obviously that means you should change it if you move to a different address, but the chip should also be updated if you get a new phone number or stop using the email address that’s listed on the chip.
Seems like there would be some timing issues with that... 50% duty cycle, the time between rising and falling edges is roughly 1.16 Microseconds (again, verified on a scope).