Data processing device, data driving device and system for driving display device

A data processing device comprising:

• a lock monitoring circuit to receive a lock signal from a data driving device and to check a level of the lock signal;
• a transmitting circuit to transmit a low-speed communication clock signal and a setup data signal to the data driving device in a low-speed communication mode, and then, to transmit a high-speed communication clock signal to the data driving device after changing from the low-speed communication mode into a high-speed communication mode, wherein the setup data signal comprises data for setting a high-speed communication environment in the data driving device;
• a control circuit to activate the low-speed communication mode to transmit the low-speed communication clock signal using the transmitting circuit when power is supplied, to transmit the setup data signal using the transmitting circuit after the lock monitoring circuit confirms that the level of the lock signal is changed from a second level into a first level when the transmitting circuit transmits the low-speed communication clock signal, and to activate the high-speed communication mode to transmit the high-speed communication clock signal using the transmitting circuit when the lock monitoring circuit confirms that a level of the lock signal is maintained at the first level.

A system comprising:

• a data processing device to activate a low-speed communication mode to transmit a low-speed communication clock signal and then a setup data signal when power is supplied, wherein the data processing device transmits the setup data signal when receiving a first level of a lock signal while transmitting the low-speed communication clock signal, and to activate a high-speed communication mode to transmit a high-speed communication clock signal when continuously receiving the first level of the lock signal;
• and
• a data driving device to receive the low-speed communication clock signal to perform low-speed clock training, to transmit the first level of the lock signal to the data processing device when the low-speed clock training is completed, and to receive the high-speed communication clock signal to perform high-speed clock training, wherein the data driving device continuously transmits the first level of the lock signal to the data processing device from a reception of the setup data signal in the low-speed communication mode to a performance of the high-speed clock training.