Wixel goes to App Stopped

I have a wixel that quickly goes to “App Stopped” even when using one of the standard apps like wireless_serial.

That wixel also does not go to the bootloader mode when I put P2_2 to 3.3v. I have even tried to do the !reset.
It seems to load apps when using wixelconfig or wixelcmd write since the red led lights up when I do the write.

I have other wixels and they do all of that fine. Any ideas?

I should mention that I am running Ubuntu 11.10, but have access to a windows laptop if needed.

Hello, joeloguete.

I’m sorry you are having trouble with the Wixel.

The “App Stopped” state indicated by the Wixel Configuration Utility is the same thing as “bootloader mode”. In your first sentence, it sounds like the Wixel is jumping into bootloader mode when it shouldn’t. This could be caused if P2_2 is somehow shorted to 3.3 V when you are trying to run the app. In your second sentence it sounds like the Wixel is NOT jumping into bootloader mode when it should.

Please disconnect everything from the Wixel and short P2_2 to 3.3V with a wire as shown here:
While they are shorted, plug the Wixel into USB on your Linux computer. After plugging it into USB, you should disconnect P2_2. What do the green, yellow, and red LEDs do at this point? Could you run the “lsusb” command and paste the output here?


when I plug in the usb, the red light is off, the yellow light stays lit and the green light blinks twice pauses (off) then blinks twice (repeats).

After disconnecting the jumper, the red light stays off, the yellow light goes off, and the green light continues to flash twice, pauses (off) and repeats.

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 003: ID 13d1:abe6 A-Max Technology Macao Commercial Offshore Co. Ltd. Wireless 802.11g 54Mbps Network Adapter [RTL8187]
Bus 004 Device 002: ID 03eb:21fe Atmel Corp.
Bus 002 Device 002: ID 046d:c00e Logitech, Inc. M-BJ58/M-BJ69 Optical Wheel Mouse
Bus 003 Device 002: ID 413c:1003 Dell Computer Corp. Keyboard Hub
Bus 003 Device 003: ID 413c:2010 Dell Computer Corp. Keyboard
Bus 002 Device 008: ID 1ffb:0100

It looks like you successfully got your Wixel into bootloader mode. The green LED is double blinking and your computer recognized a device with vendor id 0x1FFB (Pololu) and product id 0x0100 (Wixel USB Bootloader). The red LED being off indicates that you have an app loaded on to your Wixel.

Are you sure the yellow LED turned off? If so, this probably indicates there is some damage to the hardware, because the Wixel USB Bootloader should usually be driving P2_2 high, which turns on the yellow LED.


I have a total of four wixels since I want to control two remote devices from one host. I would like to know what is damaged so I can surmise what damaged it and see if there are steps to prevent any issues with the other wixels.

Is there any way to diagnose this further? Like you said the bootloader seems to do its job and is loading the wixel, but it seems that the program is not being executed. If the diagnoses can’t be done by me, do you have the capability if I send it back to you?

It sounds like the P2_2 line is malfunctioning. Did you ever connect that line to anything other than 3.3 V? Did you ever put software on the Wixel that actually drives the line low? Did you do anything unusual to the Wixel that might have caused a short circuit?

Please contact us directly if you would like to send that Wixel back to us so we can take a look at it. We probably won’t be able to tell what caused the problem but we could at least learn a little more about it.


You asked me if I wrote any software that drove that line low. Do you mean something like: LED_YELLOW(0)? I see a lot of LED_YELLOW(0) or LED_YELLOW(1) in the standard led service routines. wouldn’t that drive that line low?

I will send it to you (sending email now). I’ll pick this thread back up once I get the results.

No, LED_YELLOW(0) just sets P2_2 to be an input. If you have more questions about what our preprocessor macros do, you can find the definitions of them in the Wixel SDK directory in libraries/include/.