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  • Bill Levien thinks this is interesting:

The I2C bus is a serial protocol that consists of two physical wires that can operate in both directions. These two lines are known as the serial data line (SDA) and the serial clock line (SCL). These two lines normally operate at 3.3 V or 5 V. Although the I2C standards do permit other voltages, they are not widely seen.

  • The SDA is where the transmission of data to and from the slaves/master occurs.
  • The SCL’s job is to set the timing on the bus. It’s also used to set flow control for the data on the SDA.

By default the SDA and SCL are pulled high via a pull-up resistor (recall that we also lear...


Cover of Practical Raspberry Pi


I2C protocol on #RaspberryPi for use with an LCD