PCA9685 -> Jetson TX1 I2C Communication Write Byte Error

Robotics & Edge Computing Jetson & Embedded Systems Jetson TX1
1

I tried connecting PCA9685 Servo Controller to Jetson TX1 through I2c Bus 1.
using the command i2cdetect it is showing me that the address of the device is 40.
Pinout -
GND J21-2 → PCA9685 (GND)
VCC J21-6 → PCA9685 (VCC)
SCL J21-28 → PCA9685 (SCL)
SDA J21-27 → PCA9685 (SDA)

I used the following code GitHub - jetsonhacks/JHPWMDriver: Adafruit 16 Channel Servo Driver for NVIDIA Jetson Development Kit
but while running the servoExample it’s showing me the error WriteByte Error: 9.
Also, this issue is currently open on the Github repository. How to resolve this issue?

Also how to connect Arduino through I2c Bus 0 to Jetson TX1. I was not able to find relevant tutorials regarding it.

2

Hi, there is address conflict on 0x40. J21-3 and J21-5 are for Bus 0 (3V3).

3

I changed to Bus 0 and ran it with root permissions and the code worked. Thanks for the support.
I wanted to extend more I2C devices on the same bus or different bus.
PCA9685 Servo controller has SDA and SCL pins to connect more devices in series. I tried adding an I2C slave to the pins but the slave is not detected. Only 0x40 and 0x70 are shown using the i2c-tools.
I also tried connecting the same sensor to bus 1, but there was no address detected either. What might be the issue?

4

I think you’d better to ask vendor for help, it seems like a driver problem of PCA9685.

Regarding the sensor to bus 1, what’s the address of the sensor? Basically the I2C bus itself should have no problem.

5

The i2cdetect tool is not showing any address on the bus 1. With the same sensor connected to bus 0, the i2cdetect tool is showing the address 0x70.