Replies to This Discussion

Permalink Reply by Mike Mogenson on July 27, 2010 at 12:23pm

After looking though the board schematics it looks like the x acel = pin 0, y acel = pin 1, z acel = pin 2, z gyro = pin 3, x gyro = pin 6, y gyro = pin 7 where x is pitch, y is roll, and z is yaw.

When I test the gyro pins 6, 7, and 3 with a simple print analogRead() to serial program, the results are static. Are my gyros broken?

As a side question, which sensor corresponds to which variable, AN[0] to AN[5] in the arduimu program?

• ▶ Reply

Permalink Reply by Ken on July 27, 2010 at 3:15pm

>When I test the gyro pins 6, 7, and 3 with a simple print analogRead() to serial program, the results are static.

You are rotating the IMU during the tests, right?
Remember that they are rate not position gyros. The output only changes when the device has a rotation rate (is turning).

• ▶ Reply

Permalink Reply by Mike Mogenson on July 27, 2010 at 3:58pm

Yes, I've tried rotating each axis one at a time and waving it around like a mad man. I should see something from analogRead(6), 7, or 3 correct?

• ▶ Reply

Permalink Reply by Ken on July 29, 2010 at 6:02pm

I think that 0,1,2,3,6, and 7 are the right ADC pins for V2. However the ArduIMU code does a lot of things such as setting the reference voltage, creating interrupt procedures, etc. to get things to a known state and does some filtering.

So, if you are trying to roll your own code, you might have to do a few of these things yourself (especially the reference) before analogRead gives you what you want.

Why not start with working code? Upload the ArduIMU firmware. Look in arduimu.pde, about 37 lines down, more or less. Look for:

#define PRINT_ANALOGS 0 //Will print the analog raw data

change that to

#define PRINT_ANALOGS 1 //Will print the analog raw data

(change 0 to 1)

Now, the analog values will be sent back over the serial -->USB-->your computer.

• ▶ Reply