IRIG-B direct current code decoding method

The present invention relates to an IRIG-B direct current code decoding method. The method comprises the following steps of: the step 1: capturing one pulse rising time, and starting delay timing; thestep 2: continuously performing delay 3ms for three times, reading one IO port input state at each delay, and recording a value of 1 or 0; the step 3: determining a type of a code element according to three record values in the step 2, wherein '000' is a code element 0, '100' is a code element 1, and '110' is a code element P; the step 4: performing delay 4ms, reading one IO port input state, andrecording a value 1 or 0; performing delay 3ms, reading one IO port input state, and recording a value 1 or 0; performing delay 3ms, reading one IO port input state, and recoding a value of 1 or 0; the step 5: determining a type of a code element according to the three record values in the step 4, wherein '000' is a code element 0, '100' is a code element 1, and '110' is a code element P; and thestep 6: repeating the step