Using Pan Tilt Hat with two axis camera mount pre assembled. I’m using only the two servos and not the light bar. On RPi 3. Not your standard configuration in several ways. I already have items plugged into the GPIO header, so I can’t mount the PCB on the header. I have wired from header 3v, 5v and gnd to the pcb farside where I put pins in Power and I2C. I am using I2C-1, so I wired GPIO_2 SDA and GPIO_3 SCL to the I2C pad pins. Next I’m writing in C. I have a working I2C library from other work. I implemented the functions as shown in panthilt-hat-master/library/pantilthat/pantilt.py. The code runs, the I2C slave chip responds. i2cdetect finds the chip. i2cdump will show the registers used (0, 1 & 3) have expected values. Eg, enabling both puts 0x3 in reg 0. Setting position to 1449 us (centered) puts 0x05a9 in Reg 1,2. The supplied servos work with other code and direct connect to pwm0. Another servo of mine doesn’t work either with the hat. My servo will vibrate and shake, but not otherwise respond. Your servos have no feeling of moving or trying. I have verified 3v and 5v supply on the board, but have not/cannot look at the pwm signals. Some thing I think about: with out the hat on the expansion connector are all the required connections made with just wires from J8-2 5v, J8-1 3.3v, J8-6 GND, J8-3 i2c-1 SDA, J8-5 i2c-1 SCL individually to farside POWER and I2C pads? That is, the board should work if not plugged in but is wired like that. Please advise. I’m out of ideas.
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