With Magnetic pen long press "FUNC" button for about 5 seconds, Pressing ▲(plus 1) ,▼ (minus 1) and◀ (left)" regulation to display "1111", press "FUNC" 5 times, into "20-04" the current adjustment menu, press ▲ (plus 1 ),and ▼minus 1 in order to regulate the current between the “I+”and “GND”is 4mA, at the same time zero calibration of controller;Pressing ◀ (left), pressing  ▲ (plus 1), ▼ (minus 1)" regulation of current between the “I+”and “GND”is 20mA. At the same time, the range of the controller calibration (calibration to full range).