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Old 03-25-2016, 12:13 PM   #2692 (permalink)
thingstodo
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Join Date: Sep 2010
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Quote:
Originally Posted by WindyDrew View Post
A few things.
Quote:
Maybe 1 extra input for the brake? It would be tied high, Active low, grounded by the switch.
Quote:
How about just running the source ground through the brake switch before going to the reverse switch?
Hmm. I was looking to ignore a reverse signal unless the brake was pressed, speed was about 0, but then have the reverse signal maintained for as long as you wanted to back up.

The wiring through the brake has the reverse signal go away when the brake is released. How do you signal that you want to go forward again? When the brake is pressed again and no reverse signal is there?

In terms of coding, it is preferable to have signals coming from off the MPU that show you what mode you are in. You can keep track in software, but each time you do you need to bullet-proof the conditions for entering and exiting that mode, complete with what could go wrong/fail and get you into that scenario unexpectedly.

If it was my car - I'd use the extra input and make sure the rpm on the car was under a threshold, like maybe 50 rpm. An indication that you are in reverse and not forward would be nice as well.

Are you using regenerative braking? If so, how does the brake signal get tracked now?
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