Are the demo programs ready to run?

Added by Trevor Davies almost 3 years ago

As the title says, are the chase/track/hello world programs "good-to-go" or do I need to modify them? I just can't get them to work.
When I run the hello world program, the object does not appear on the EV3 screen, just a crescent in the top right hand corner. When I try the chase program, the EV3 just continues forward, and when I run the track program, it just goes in circles.
I have checked Pixy separately on the tilt and turn and it works as expected, and the led shines correctly when the object is in front when running all the programs,
My Pixy is a 1.3A, so should be OK. I am running firmware v1.09 on the EV3.
I bought the Pixy/EV3 lead from Amazon, but the 10 pin connector fell apart when I pulled it from Pixy, so I have used your instructions in the wiki to make a lead with a ribbon cable.
What am I missing? Can anyone suggest any further checks I can do if the programs should run as is? (I have to say, they don't look identical to the pictures in the wiki).
Many thanks in advance.

Replies (3)

RE: Are the demo programs ready to run? - Added by Edward Getz almost 3 years ago

Hello Trevor,
The programs should work without modification. First, we should get you a replacement cable. We'll have someone contact you to get that handled. Also, I'm not sure which firmware you are running, LEGO or general. If you are running general, make sure you are setting the interface to LEGO i2c:

You also need to be running the default program in order for Pixy to communicate what it sees to the LEGO brick (see step 6 here):


RE: Are the demo programs ready to run? - Added by Trevor Davies over 2 years ago

OMG, Edward, I cannot believe I missed that! Thank you so much.
Changed the interface to LEGOi2c and everything works perfectly. Thank you. (I feel such a fool :-( ).
One last question. In your demo video for the chase program, towards the end you demonstrate the EV3 with a grabber, picking up objects and moving them. Have you published details of this routine anywhere ie construction and program? I can visualize many adaptations for this and would love to have a play with it.
Many thanks once again, and don't worry about the cable, my homemade one works just fine.


RE: Are the demo programs ready to run? - Added by Edward Getz over 2 years ago

Hello Trevor,
Glad you got it working! The pickup demo is something we haven't documented (sorry!) I believe it was fairly straightforward though, just a simple state machine. Let me know if you have specific questions and I'll try to get them answered.