Hello,
I have uploaded my E-I2C DEVICE SEEK software for you to try.
https://www.roboternetz.de/phpBB2/dl...le&file_id=311
This software will check all the I2C 7 bit addresses for any device connected to the E-I2C bus and display the address(es) on a terminal program.
This way we can make sure that the SD20 is reacting.
My software uses port[1] as SDA and port[2] as SCL.
Make sure to disconnect the servo first and let me know if the terminal program displays any found I2C devices.
Greetings,
H.J. Windt