The driving circuit of the display includes a timing controller. The timing controller is coupled to a general purpose input/output (GPIO) pin of the touch driver. The timing controller receives an instruction signal via the general purpose input/output pin of the touch driver. The timing controller starts a detection period according to a main falling edge of the instruction signal. The timing controller determines a current operating status of the touch driver according to a number of sub-falling edges of the instruction signal during the detection period.