Wire (I2C)

setSpeed()

Sets the I2C clock speed. This is an optional call (not from the original Arduino specs.) and must be called once before calling begin(). The default I2C clock speed is 100KHz and the maximum clock speed is 400KHz.

// SYNTAX
Wire.setSpeed(clockSpeed);
Wire.begin();

Parameters:

  • clockSpeed: CLOCK_SPEED_100KHZ, CLOCK_SPEED_400KHZ or a user specified speed in hertz (e.g. Wire.setSpeed(20000) for 20kHz)

Gen 4 Devices (RTL872x) (P2, Photon 2, and M-SoM):

On the P2 and Photon 2 the only valid values are CLOCK_SPEED_100KHZ and CLOCK_SPEED_400KHZ. Other speeds are not supported at this time.