CHR um6 lt and Wixel - Broadcast rate problem

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1

Hello guys,

for my application I use :
chr um6 lt sensor : pololu.com/product/1256/resources
and Wixel : pololu.com/product/1336 - configured to USB-to-UART converter

I have set everywhere 115200 baud rate, even on Device manager on COM port.

Problem is that no matter which Broadcast rate I set in CHR interface I always get time vector steped with 0,0625s which is 16 Hz. I would need sampling at least at 50 Hz.

Best regards,

2

Hello.

Is this the same problem you mentioned in this thread? If so, could you continue the discussion there?

- Jeremy

3

Hello,

it is not the same problem. In previos post I had problems with non-uniform time spacing.

Now i bought CHR um6 lt and the problem is Broadcast rate which doesn’t change if I change it in Software (CHR Serial Interface 3.0.5).

Best regards,

4

Are you able to change other settings with the CH Robotics Serial Interface? If so, I suspect there might be an issue with the UM6-LT. We do not manufacture that sensor. You might try contacting the manufacturer, CH Robotics, directly for further troubleshooting.

- Jeremy

5

Yes I can change other settings. I can also change Broadcast rate but when I log to file there is no change.

I already contacted CH Robotics, but for now I got no response.

I just saw my mistake can be in power supply. I am supplying sensor with Wixel’s 3,3 V which is 0,2 V lower that minimum required. Can this be a reason for that?

I am planning to solve this problem with : pololu.com/product/791/
I chose this because it is in stock here at your distributor in Slovenia :slight_smile:

I would very appreciate any advice here,

Best regards,

6

According to the CHR-UM6 datasheet, the input voltage range for the UM6-LT is 3.3 to 5 V (the non LT version has a range of 3.5 to 5V). I expect the UM6-LT to work when powered by the Wixel’s 3.3V output. Could you try measuring that pin to make sure it is supplying 3.3V?

- Jeremy

7

Hey guys,

I’m from CH Robotics and can help. The logging code in the CHR Serial Interface logs at a fixed rate (~16 Hz) regardless of how fast it receives data from the sensor. At this time (version 3.0.5) higher logging rates aren’t supported.