Thread: Unable to read accelerometer
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Unread 15-02-2012, 20:13
StephenNutt StephenNutt is offline
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FRC #0172 (Falgor)
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Re: Unable to read accelerometer
I borrowed a Total Phase Beagle I2C analyser from work and have some additional info.

When successfully reading the I2C bus from an Arduino the clock speed is 100kHz. When unsuccessfully using the cRIO the clock speed is 38.4kHz (the Beagle reports the clock as every 26us)

The accelerometer is not acknowledging with an ack - the SDA line is not going low after after the final bit is sent from the cRIO.

Does any team have an oscilloscope and can measure the clock speed for me. Our oscilloscope is giving us a clock speed of closer to 43kHz.

Additionally, we are currently using the old 8 slot cRIO. Has anyone managed to get the accelerometer going with last years cRIO rather than the new 4 slot cRIO?

Again, many thanks to all for any help

Steve