Patent ID: 8645020
Filing Date: 2014-02-04
Classification: G01P,G07C,H02M,H04L

Abstract:
1. A system for performing at least one diagnostic check on a first data message transmitted from a sensor unit to a receiver unit, the system comprising: a receiver clock tick counter for determining a length of a first portion of the first data message using a receiver clock signal by determining a count of clock cycles of the receiver clock signal during receipt of the first portion of the first data message, wherein the receiver clock signal is generated using a high frequency (HF) clock signal; a prescaler counter for receiving the HF clock signal, generating the receiver clock signal, and determining a length of a second portion of the first data message using the HF clock signal by determining a count of clock cycles of the HF clock signal during receipt of the second portion of the first data message, wherein the length of the second portion of the first data message is a fraction of a pulse width of the receiver clock signal; a calibration pulse detector, connected to the receiver clock tick counter and the prescaler counter, for detecting a first calibration pulse in the first data message by comparing the length of the first portion of the first data message with a valid pulse length range when a negative edge is detected in the first data message, and generating a calibration pulse detect signal when the first calibration pulse is detected in the first data message; at least one calibration pulse parameter register, connected to the receiver clock tick counter, the prescaler counter, and the calibration pulse detector, for storing the counts of clock cycles of the receiver and HF clock signals corresponding to the first calibration pulse and a second calibration pulse transmitted from the receiver clock tick counter and the prescaler counter upon detecting the first and second calibration pulses, wherein the second calibration pulse corresponds to a second data message received immediately before the first data message; a diagnostic control state machine, connected to the calibration pulse detector, for initiating the at least one diagnostic check on the first data message; and calculation logic, connected to the diagnostic control state machine, for performing the at least one diagnostic check and generating a diagnostic check signal to indicate at least one of pass and fail status of the first data message, the calculation logic comprising: