An electronic system for transmitting and receiving internal data through an optical channel. The electronic system may include a light emitter configured to generate a first optical signal, a first device configured to receive the first optical signal and including a transmitter configured to output a second optical signal representing a transmission value based on the first optical signal, a second device including a first receiver configured to receive the second optical signal from the first device and output a third optical signal by adjusting a light intensity of the second optical signal, and configured to read the transmission value based on the light intensity of the second optical signal, and a third device including a second receiver configured to receive the third optical signal from the second device, and configured to read the transmission value based on a light intensity of the third optical signal.