Hi,
if unused, I2C bus ist logical HIGH (5V oder 3V3 or whatever "high" ist defined).
After starting up FC, the bus is used, so you can see the communication with a I2C sniffer or simple waveform monitor.
Voltage should then be anything between high and low (5V and 0V) - depends on your method to measure the voltage.
Communication protocol is defined in the source code on svn. I2C hardware specs is found on internet, or in controller
datasheet (here named as "TWI Interface" (copyright reason, the real "i2c" standard is owned by Phillips, iirc)
Tim1
if unused, I2C bus ist logical HIGH (5V oder 3V3 or whatever "high" ist defined).
After starting up FC, the bus is used, so you can see the communication with a I2C sniffer or simple waveform monitor.
Voltage should then be anything between high and low (5V and 0V) - depends on your method to measure the voltage.
Communication protocol is defined in the source code on svn. I2C hardware specs is found on internet, or in controller
datasheet (here named as "TWI Interface" (copyright reason, the real "i2c" standard is owned by Phillips, iirc)
Tim1