Patent ID: 8082377
Filing Date: 2011-12-20
Classification: G06F

Abstract:
1. A master device for performing data transmission and reception with a slave device, the master device comprising: a data transmission and reception circuit for performing transmission of data to the slave device and reception of data from the slave device via a first transmission path in a time division manner; and a control circuit wherein when data is transmitted or received, the control circuit provides a clock signal synchronous with the data to the slave device via a second transmission path, the control circuit provides a signal for setting a state of the slave device, to the slave device via a third transmission path while setting the clock signal at a first level, and the control circuit provides a signal for serving as a trigger for the slave device performing a predetermined operation, to the slave device via the third transmission path while setting the clock signal at a second level different from the first level, wherein the slave device includes a second data transmission and reception circuit for performing transmission of data to a second slave device and reception of data from the second slave device via one transmission path in a time division manner and a second control circuit, the second control circuit relays a clock signal to the second slave device, and while setting the clock signal at a second level, the second control circuit masks a change in level of a signal received from the master device via the third transmission path and relays the signal to the second slave device, the second slave device obtains a count value by counting the number of pulses included in a clock signal and inverts a communication direction on the basis of the count value, and the communication direction of the second slave device is inverted based on the count value after a communication direction of the slave device is inverted.