Gryo Connection

[EricWilliams]

Last night after wiring up the KOP gyro we weren't able to get any reading. We hooked up a 100k pot to the same channel of the Analog Bumper and were able to get correct readings. Does the KOP gyro need to have the TEMP outputs wired to operate? We only hooked up the RATE output.

[rwood359]

Originally Posted by Ewilliams2006

Last night after wiring up the KOP gyro we weren't able to get any reading. We hooked up a 100k pot to the same channel of the Analog Bumper and were able to get correct readings. Does the KOP gyro need to have the TEMP outputs wired to operate? We only hooked up the RATE output.

The gyro works OK without the TEMP connected. We have been using it that way and the stock VIs don't have an input for TEMP.

[EricWilliams]

Well I'm at a loss with this one. We've done conductivity tests on all of the wires and used both the default LabView VI and WPILib example to try to get a reading from the gyro - both with no success. We soldered the male end of a PWM cable into the RATE pins, with the signal (white) pin closest to the RATE label.

[EricVanWyk]

Can you describe what signal you are getting and show us your code?

It is also possible that you received one of the units that had the labels for Rate and Temp swapped, but I believe those came with notes clarifying the mistake.

[Tom Bottiglieri]

Originally Posted by EricVanWyk

Can you describe what signal you are getting and show us your code?

It is also possible that you received one of the units that had the labels for Rate and Temp swapped, but I believe those came with notes clarifying the mistake.

The signal was pretty constant with a bit of noise, around 10 mV. It peaked at ~0 and ~20mV.

This has been tested with 2 of the 2009 kit gyros. Both produced similar results. We borrowed another local team's unit to test with, so if a bad batch (reversed R/T labeling) was sent to our regional kickoff, that could be the issue.

As Eric stated above, we tested this with the sample gyro code in LabView and using C++. The accumulator for the gyro angle was going through the roof, which matches up with the relatively low signal. I am almost certain this is not a code issue.

[EricWilliams]

Originally Posted by EricVanWyk

Can you describe what signal you are getting and show us your code?

It is also possible that you received one of the units that had the labels for Rate and Temp swapped, but I believe those came with notes clarifying the mistake.

We tried it again when it wasn't almost midnight and it worked right off the bat. One question we still have is why the Gyro Example distributed by NI didn't have the correct Volts/deg for the 2009 KOP gyro?

[EricVanWyk]

Originally Posted by Ewilliams2006

One question we still have is why the Gyro Example distributed by NI didn't have the correct Volts/deg for the 2009 KOP gyro?

The example was written and verified before the 2009 KOP gyro was available.

[Russ Beavis]

I just helped a local team and quickly learned that they received an old rev of the gyro board. The "Rate" and "Temp" labels on the PCB's silkscreen were mistakenly swapped. They were measuring temperature instead of rate.

If your PCB isn't labeled as shown as in the gyro schematic (link below) , you received an early rev board with swapped labels and will need to wire to the "Temp" output to actually measure rotation rate. Sorry for the inconvenience.

http://www.usfirst.org/community/frc....aspx?id=11838

Russ