The invention relates to a program-controlled multi-channel variable
resistor and a resistance value adjustment and control method thereof. The variable
resistor comprises a
communication interface, a multi-channel resistance output interface, a single-
chip microcomputer and at least one single channel, wherein the
communication interface is connected with an upper computer of a
control system, each single channel comprises a
digital potentiometer and an electro-static
discharge protection
chip which form a series
branch, communication is carried out between the single-
chip microcomputer and a
serial port conversion module by a universal asynchronous
receiver /
transmitter (UART) three-wire interface mode, the single-chip
microcomputer and the digital potentiometers are arranged through an I<2>C communication mode, or the tap position or the resistance value of the current
digital potentiometer are read. The adjustment and control method comprises the following steps of 1) testing a
serial port; 2) carrying out direct program-controlled reading and adjustment on the resistance value of the
digital potentiometer of an appointed channel; and 3) periodically calibrating the resistance value of the digital
potentiometer of each channel by a
multimeter. The program-controlled multi-channel variable
resistor and the resistance value adjustment and control method thereof have the advantages of simplicity in composition, convenience in use and accurate and reliable resistance value, the
embedded software of the single-chip microcomputer can use the resistance value correction
linear coefficient of each channel to automatically correct the resistance value, and the accuracy of the resistance value of the variable resistor is guaranteed.