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Old 03-25-2016, 01:31 PM   #2693 (permalink)
WindyDrew
AC Customs car builder
 
Join Date: Jan 2009
Location: Kansas
Posts: 51

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Quote:
Originally Posted by thingstodo View Post
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?
My plan required holding the button down for reverse. Once I let off, it would be forward. So having close to 0 rpm would be a good idea. But I also want regen so only restrict forward to 0 rpm. Once it's in drive, I want to use it as a regen pedal when I'm holding the button.
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