Can a pic do several things at once?

[Squibcakes]

I would have considered that but I've already got something similar, its my speedometer, my reason for wanting to do the above is the accuracy of speed derived from GPS signals, where using sensors on the driveshaft or anywhere else will never be anywhere near accurate due to tyyre sizes, and even the tyre pressure dropping would change the speed reading's accuracy thats why I ruled out sensors on the cars mechanical bits

Well thats your call, but as others have said, this approach would be more accuate than a gps. Whats more, the car needs to be moving to get an accurate speed (and direction). It would look a bit funny when your stopped at the traffic lights and your display shows you are moving at 1mph. I guess you need to take this into concideration and perhaps using a sensor on the shaft show zero speed when the car is stopped.

Oh yeah, and as far as nmea is concerned, the pic (speed) can handle it just fine untill the you start processing very long strings where you run out of memroy.

One problem I have had though is when sitting in a waitstring($GPVTG) waiting for that string to arrive, the pic can't do anything else. In those cases you could use a second pic just.... but then it all starts to get messy.

Thats my 2c worth.

Squib

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