I recently bought Quad Power Management board and attempted to test it using . The program should turn on and off load switches. I attempted to test it by connecting the board to the Raspberry Pi using I2C pins SDA, SCL, GND, VDDM on JP2, put 5V between VIN0 and GND on LoadSwitch0 and from VOUT0 and GND I fed another RPi - these were connected to RPi GPIO. I expected that RPi will turn on and off accordingly but nothing happened. On top of that - shouldn't be that status of on/off of particular load switch indicated by LED's on the board? Only LED that was "ON" all the time was the power LED but no other.
I also tried to short SJ1 pins and power up the board as this should cause the power switch to be in "ON" state upon QPM power on. But I'm still getting the same result - 0V between VOUT and GND. Tried to apply 5V to LoadSwitch1 but still no luck.
The question is - is the board faulty? Or I'm doing something wrong?
All loads are disconnected, the board itself is detected, the program is running. When I disconnect SDA and SCL and have only power applied then the program crashes. So some communication is with the board is happening but it seems that it doesn't accept power-on commands for the load switches. Any other ideas? I can try to do some measurements with multimeter if tell me what should I test.
I have finally received the replacement QPM board but the behavior is still the same. :-( This time I didn't connect any loads at all, connected only I2C cables and used Arduino Uno to do the tests. Serial console looks fine, Arduino finds the QPM, however individual LEDs are still off during the test loop. This cannot be coincidence that two boards behave exactly the same... Wasn't there some change in components addressing or something?
Have you got a chance to test the board I sent you back?
I have uncommented part of the QPM test code that does I2C detection, the output is:
-------------------------- SDL_Arduino_QPM_Test Version 1.1 I2C device found at address 0x21 done
------>>>> Initial GPIO Value =81 ---------------- Turn on LSW0 Turn on LSW1 Turn on LSW2 Turn on LSW3
So, the device is found at default 0x21 address. However if you want, I can connect the board to RPi and run i2cdetect -y 1 there. However, it doesn't seem that I2C comms between Arduino/RPi vs QPM is the problem. For me its seems like the load switches weren't properly addressed by the chip that sits between I2C and load switches themselves. Just my 2c.
I just received my QPM and it exhibits exactly the same behavior. By the way, "your switches were working already" is incorrect. The switches only work after providing power to JP4/1.
You may want to update the documentation to mention that at least JP4/1 needs to get some power - either from JP3 (which means the I2C host needs to be alive) or from another 5V source (for example the SunControl board)
Last Edit: Jan 27, 2019 11:08:58 GMT -8 by lbendlin