PCI-based IRIG-B decoding card

The utility model discloses a PCI-based IRIG-B decoding card which comprises a PCI card body, a direct-current B code decoding unit, and/or a direct-current difference B code decoding unit, and/or an alternating current B code decoding unit, wherein the last three units are disposed on the PCI card body. The PCI-based IRIG-B decoding card also comprises a time information processing unit, a second signal time-delay processing unit, and a millisecond counter, which are all disposed on the PCI card body. According to the utility model, accurate second pulses can be obtained by the second signal time-delay processing unit. The accurate second pulses are read by a computer via a PCI bus and capable of making the time accuracy of a whole computer system be improved greatly, which facilitates the cooperative processing of the system and meets expected requirements.