Sonar working but can't read values after update to 3.1

ArduCopter Copter 3.1
1

Hello,

I’m seeking some help because I’m stuck: after upgrading to AC 3.1, I can’t read my XL_EZ0 sonar anymore.

I’ve tested the voltages, and when plugged in to my APM 1, the sonar is working (+5V on vcc, ~100mV out on ANALOG pin for ~20cm), but I can’t read any value with the terminal/test/sonar function, nothing appears.

I’m using the lastest mission planner software and the 3.1 AC firmware.

The sonar used to work with my APM1 and older versions, so I’m wondering if it could be a recent APM 1 hardware failure or if it could be related to the upgrade to 3.1 firmware ?

I had a look at the sonar parameters in the mission planner, and everything looks good to me (sonar enabled, gain at 0.8, type == XL_EZ0).

Thanks for your help!

Regards,

Nicolas.

2

I tried with old firmwares (2.9 and 3.0.1), and the sonar test is OK with them, so it seems that there’s a bug in AC 3.1 with sonar on APM1 boards (a b 2560)…

3

I’ve been pulling my remaining hair out with this too. Using a scope to look at the output. I have a model 1240 that I think be a lot better. Not thru troubleshooting tho.