Can I use a [Zio Current and Voltage Sensor - INA219 (Qwiic) to measure the total current of all the other Qwiic devices on the same I2C bus?](Zio Current and Voltage Sensor - INA219 (Qwiic) - SEN-15176 - SparkFun Electronics)
It would appear if all I’m after is the current I can just insert the INA219 into the Qwiic power or ground.
Given the diagram (below), am I correct in assuming the total current-handing capability will be the sum of the Raspberry Pi and SparkFun Thing Plus - SAMD51 current-handing capability?
The Qwiic connectors only supply power and data to the INA219, they don’t provide any current sensing. In your picture, you’d only be measuring current to the devices on the right hand side of the INA219 but I’m not sure the hookup would work. If you’re providing power to the SAMD51 board, you don’t want to provide power from the Pi as well. Also the Pi and SAMD51 are both I2C hosts, you would need to make the SAMD51 a slave or you’re going to have bus issues.
TS-Chris:
The Qwiic connectors only supply power and data to the INA219, they don’t provide any current sensing. In your picture, you’d only be measuring current to the devices on the right hand side of the INA219 but I’m not sure the hookup would work.
That’s what I was after (the current of the devices on the righthand side of the INA219).
If you’re providing power to the SAMD51 board, you don’t want to provide power from the Pi as well.
So the Pi would power the SAMD51 board via I2C?
Also the Pi and SAMD51 are both I2C hosts, you would need to make the SAMD51 a slave or you’re going to have bus issues.
I know that some SparkFun microcontrollers can simultaneously function as both a controller (master) and peripheral (slave). Apparently, the SAMD51 isn’t one of them. I’ve been experimenting with dynamically switching the SAMD51 between controller and slave. It works to an extent, but as you point out, it has its issues.