AX2850 spurious Estop

7 years 4 months ago #29528085 by sroth44489
I am using an AX2850 and am having a problem with spurious estops. When the vehicle is asked to accelerate or decelerate quickly, occasionally the controller will detect an Estop. I am using the estop functionality in the controller, and I have a switch connecte that should pull the Estop to ground. However, this is never pushed. I\'ve swapped out the entire wiring harness and swapped controllers trying to track down the source of this problem. Nothing has solved it.

When the vehicle stops, querying the state of the controller with ^89 returns 80, indicating an estop. Using ?i to get the state of the inputs, I get 01 00 01 indicating the Estop switch is high (not pressed).

I don\'t understand where this spurious estop is coming from. Any ideas how to solve this?

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7 years 4 months ago #29528086 by Griffin Baker
Replied by Griffin Baker on topic Re:AX2850 spurious Estop
The e-stop that you are using, is it a switch, or some sort of relay connection in your setup? I assume that this is plugged into your +5V and your Input E or F.

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7 years 4 months ago #29528087 by sroth44489
Replied by sroth44489 on topic Re:AX2850 spurious Estop
It is a switch.

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7 years 4 months ago #29528088 by Griffin Baker
Replied by Griffin Baker on topic Re:AX2850 spurious Estop
Is this switch wired between your +5V and your E or F pin? Or is this wired to GND and E or F pin?

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7 years 4 months ago #29528089 by sroth44489
Replied by sroth44489 on topic Re:AX2850 spurious Estop
The switch is wired between pin 15 (the ESTOP / INV pin) and ground.

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7 years 4 months ago #29528090 by Griffin Baker
Replied by Griffin Baker on topic Re:AX2850 spurious Estop
place the pin that is in gnd and connect to 5V, so that when the +5V goes high, the E-stop activates. When it isn\'t high, then no e-stop should occur.

+5V(pin 14) and Pin 15.

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7 years 3 months ago #29528091 by sroth44489
Replied by sroth44489 on topic Re:AX2850 spurious Estop
On the AX2850, the ESTOP input has an internal pullup resistor to +5V. To ESTOP the vehicle, the switch must pull that input to GND, which is how my circuit works. It works most of the time, only failing when the vehicle accelerates or decelerates sharply. That is why I think that there may be some kind of electrical noise causing this problem.

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7 years 3 months ago #29528103 by Griffin Baker
Replied by Griffin Baker on topic Re:AX2850 spurious Estop
Try using a switch that does not have this +5V internal resistor and see if wiring a regular switch from the pin 14 and pin 15 works.

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7 years 3 months ago #29528104 by sroth44489
Replied by sroth44489 on topic Re:AX2850 spurious Estop
It is not the switch with the internal resistor. The AX2850 itself has an internal pullup resistor.

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7 years 3 months ago #29528105 by Griffin Baker
Replied by Griffin Baker on topic Re:AX2850 spurious Estop
Try removing the external battery and see if the radio stays on. If this is the case, then most likely the radio and the servo are powered from the same source.

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