Asked — Edited

Counting Switch Closures

Hello all, just a quick question and I'm sure it will be simple. what I'm looking for is something to count how many times a switch closes. is there something in ARC? i want to use a switch to count wheel rotation, kinda like a encoder.

thanks, airwave1206


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is there something in ARC?


kinda like a encoder.

  1. You will need to add external hardware:
  2. add some EZ-Script to handle the external hardware.

Depends what you're attempting to do? Are you wanting to count rotation of a wheel encoder to see how far a robot has driven? Are you trying to move a head or arm a specific number of ticks? There's different solutions for different applications.

  1. You could use a hardware interrupt from a dedicated pcb, such as arduino. And connect the Arduino to the ez-b. This is because the EZ-B is already doing a significant amount of i/o processing with video, audio, wifi, servos, etc.. So offloading the counting to an arduino will work great. Send the count data to the


  1. If the rotation is slow (i.e. < 2 / second), then you can use an EZ-B v4.x/2 or IoTiny without additional hardware and simply read the digital port. If you have an onboard computer in the robot, this rotation count speed can be increased dramatically by using a USB<->Serial connection to the ez-b


  1. Use a third party motor controller with built-in encoder to offload the work, such as a Sabertooth with Kangaroo.

Obviously #2 is the easiest because it doesn't require additional hardware.


thanks everyone for the input. I've seen the arduino encoder post. DJ, I do have a on board pc and the ezb4 running on usb. I might try option #2. I was just trying something easy. thank you all.


yeah, #2 will work great for you with USB. Like i said, a slow count with #2 can work over WiFi. However, with wifi there is unpredictable delay/latency that is acute to the wireless properties and interference. With USB, it is direct and super fast.