Communication between intergrated circuits

The end of an I2C transmission is detected by connecting the serial data line to the clock of a first D-type flip-flop and connecting the serial clock line to the data input of the flip-flop. The start of the transmission is detected by connecting the serial data line to the inverting input of a second D-type flip-flop and connecting the serial clock line to the data input of the flip flop. The output of the second flip-flop is connected to the data input of a third D-type flip-flop, which is clocked from the inverted serial clock line. The output of this flip-flop is connected to the reset of the first flip-flop. It is also connected to a fourth D-type flip-flop, which is clocked from the serial clock line. The output of the fourth flip flop is connected to the reset of the first flip-flop.