HK 30A BlueSeries ESC schematic and I2C/TWI mod
I have done with drawing schematic for HobbyKing 30A BlueSeries Brushless Speed Controller
. It's mostly complete, but still can contain some bugs, errors, missing or wrong elements or values (all ceramic caps are 0.1 uF for now, lol) etc. I would be very grateful for any advices, suggestions and corrections.
The target is to re-flash this ESC with opensource firmware, add I2C and/or UART interfaces. In other words, to play with it and to gain some experience with brushless motor controllers
Now I have a couple of questions:
1) Do all of this cheap ESCs have a current sensor? I did not found any...
2) What is the point of measuring voltage at S_PWR?
3) Can't figure out, what the connections PD0-PD2 and PB2-GND are all about
4) Why do we need an middle point connection from BEMF sensors to PD6 (sorry, I'm a noob in ESCs, but I've seen similar connections in other schematics).
5) Is there any well tested C firmware, where I can just modify I/O ports? Or should I write my own?
Thanks in advance for any answer!
Here is the schematic (click for full version: 3200x2400 PNG, 357 kb)
Here are the board photos for reference:
(1637x721 JPG, 354 kb)
(1629x753 JPG, 357 kb)