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Pixy not sending data to Arduino Uno

Pixy Hardware
#1

Hi all,

My Pixy camera connected to Arduino Uno with the provided cable with the Arduino running the hello_world program, but I don’t see any data being transferred. I have a second Pixy camera which works perfectly as described in the tutorial so there is no problem with the Arduino or the cable. For troubleshooting I tapped in to the provided SPI cable connected to the first Pixy which is not sending data to arduino and I see some data being send over the MOSI pin along with clock signal (attached). So to summarize,

  1. Both pixy work with PixyMon, i.e., I can teach/store color signatures and run the pan/tilt demo.
  2. The first pixy does not send data over to Arduino. “Starting…” shows on the Serial monitor but nothing else. However the LED on the Pixy module shows some color change when I bring the one of the color signature objects in front of the camera.
  3. the second Pixy works perfectly fine using the same Arduino and cable.

Any help if troubleshooting/fixing the problem is appreciated.

Regards,
Ajay

#2

Hi Ajay,

Sorry for your troubles. So you’ve gone through the “troubleshooting”:http://cmucam.org/projects/cmucam5/wiki/My_Arduino_isn’t_receiving_data_from_Pixy guide and its still isn’t working? When testing your first Pixy vs your second Pixy, are you using the same cable and same Arduino?

Thanks.

Scott

#3

Hi Scott,

Yes I did follow the troubleshooting guide. For both the pixy units i used the same cable and Arduino board.

I want to be able to use the Pixy with other micro controllers (similar to Freescale K64F) to design a senior level project. I did some more testing to understand the working of hardware/software and have some more questions.

  1. The MOSI pin is sending 0x5A00 to the Pixy. Why is that needed (SPI.bmp).

  2. I generate a “fake clock” signal of 1MHz on one of the Arduino digital I/O pins (actually slightly less than 1MHz by setting it high and low alternatively, but fast enough to read 14 bytes of block format data without overlapping) and i think i can read all the seven words on MISO line (fake_clock.bmp) without having to send signal on MOSI.

  3. On the second Pixy unit (which works perfectly), I tried the uart and i2c Arduino code but they did not return any data. “Starting…” shows on the Serial monitor and nothing else.

Thanks again,
Ajay

#4

Hi Ajay,

0x5A00 might be one of the “start words” that indicate the start of a block in the Pixy communication.

Are both Pixy’s using the same, most up-to-date firmware? Are they trained on the same object when you’re doing the testing? Is the broken Pixy showing any life (like through the LED or in Pixymon)?

If you continue to have trouble then we may have to start an RMA for you to get it exchanged.

Thanks.

Scott

#5

Hi Scott,

Both Pixy use the same firmware, and are trained on the same object. The broken Pixy is not sending the data over the SPI/UART/I2C port. However, it does work with Pixymon via the USB cable and the front LED does work as described in the documentation.

Thanks,
Ajay

#6

Hi Ajay,

Hmm looks like it might be best to have you exchange your broken Pixy. I’ll send you an email shortly with instructions.

Thanks.

Scott

#7

Hi Scott and Ajay,

I was wondering if either of you had figured out how to fix this problem. I am experiencing the EXACT same issue as Ajay mentioned in his first post:

"My Pixy camera connected to Arduino Uno with the provided cable with the Arduino running the hello_world program, but I don’t see any data being transferred. I have a second Pixy camera which works perfectly as described in the tutorial so there is no problem with the Arduino or the cable. For troubleshooting I tapped in to the provided SPI cable connected to the first Pixy which is not sending data to arduino and I see some data being send over the MOSI pin along with clock signal (attached). So to summarize,

  1. Both pixy work with PixyMon, i.e., I can teach/store color signatures and run the pan/tilt demo.
  2. The first pixy does not send data over to Arduino. “Starting…” shows on the Serial monitor but nothing else. However the LED on the Pixy module shows some color change when I bring the one of the color signature objects in front of the camera.
  3. the second Pixy works perfectly fine using the same Arduino and cable."

I have been through the troubleshooting guide and that did not lead to the answer.

Any help if troubleshooting/fixing the problem is appreciated.

Regards,
Steven