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Dangerous bug when using KILLSWITCH and PPM, FW5.03

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corgon
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Dangerous bug when using KILLSWITCH and PPM, FW5.03

Hi Folks,

I discovered a really dangerous bug when I played with that new KILLSWITCH safety function in FW 5.03 (probably the bug present in 6.02FW too). I use to control the VESC a cruise control PPM remote (I set the needed PPM value and the controller holds that value till I cancel it or accelerate or decelerate). No need to hold the throttle. Now I set up the kill function (ADC2 Low or ADC2 High it doesn't matter, fails both) to test it. 
I set the cruise speed on the remote to hold it, the motor run at constant speed then I activate the killswitch input the motor immediately stops as it should. Important the PPM signal is still present because the remote still maintains the speed (of course, I had set Safe Start in PPM tab to Regular). But if I deactivate the killswitch input the motor immediately starts and speeds up to the set speed. The VESC ignored the Safe Start function. 
This is a very unsafe and dangerous situation in combination with the cruise control remotes. 

frank
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We can look into this and see if it is possible to add a safe start feature after the kill switch activation. In general PWM/PPM remotes are not safe to begin with. It is no dual way communication and the ESC can't know if a signal is intended or not.

corgon
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Last seen: 1 year 5 months ago
Joined: 2020-01-20 23:30
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That is why the PPM input should be automatically blocked after the safety switch is activated. After deactivating the killswitch VESC must always require safe start.