Python LED example not working?

Navio / Edge Hardware
1

Hi,

I’ve just tried to run the python example code that were released recently and, though the accelerometer/gryo and Barometer examples work very well (haven’t tried the servo nor ADC one just yet), the LED example doesn’t seem to work properly.

Looking at the code, it looks like it’s suppose to make the LED simply go through various colours… but the LED does not lit up at all and the code just prints this to the console:

Reseting PCA9685 MODE1 (without SLEEP) and MODE2
I2C: Wrote 0x00 to register 0xFA
I2C: Wrote 0x00 to register 0xFB
I2C: Wrote 0x00 to register 0xFC
I2C: Wrote 0x00 to register 0xFD
I2C: Wrote 0x04 to register 0x01
I2C: Wrote 0x01 to register 0x00
I2C: Device 0x40 returned 0x01 from reg 0x00
I2C: Wrote 0x01 to register 0x00
Setting PWM frequency to 60Hz
Estimated pre-scale: 100
Final pre-scale: 101
I2C: Device 0x40 returned 0x01 from reg 0x00
I2C: Wrote 0x11 to register 0x00
…

Anyone tried the LED example code and seen this happen? Any idea what do to to solve this?

Thanks
David

2

Hello, David
Please check if the C++ LED example is working. If it isn’t, then you must be powering your Raspberry Pi + NAVIO only with the micro usb cable. In order to get the LED working, you should either use an external power source for NAVIO, or attach a jumper cable between 5VRPI and BEC middle pins.

3

If you are powering it right the LED should come on white when you first power up on, even before the RPi has booted. If you are powering by USB, you’ll need to add a jumper from the 5VRPI pin to the adjacent BEC pin on the servo header.

Typically the USB PSU can’t handle very much current so sure you don’t overload it. It will be fine if you don’t have any servos or other high current devices plugged in.

4

Thanks for your answers, I didn’t realise this was needed for the LED… I was indeed only powering NAVIO via the usb psu.

David