A method is provided for removing a coating from a coated magnesium alloy product. According to one embodiment, for each data range of parameters to be encoded, a number of bits required to represent a maximum parameter among the parameters in each data range is determined, including a first number of bits and a second number of bits corresponding to the first and second data ranges. A power clamp unit discharges the electrostatic current, which is discharged to the first power supply line or the second power supply line by the first discharge unit, to the opposite power supply line. In another example, a method for priming a printhead assembly includes pushing liquid from a container into the printhead assembly through a liquid port and then pulling froth from the printhead assembly into the container through the liquid port. The initializing unit initializes the storage unit after a predetermined time from an activation of the driving signal. The present invention deploys two independent transmitting paths.