Functional safety high-speed counter module including diagnostics circuitry for performing counter pattern test

Abstract

A Functional Safety Counter Module is provided and it comprises input circuitry, test circuitry, a first microcontroller including a first hardware counter, a second hardware counter, a first storage device that stores a first firmware algorithm code to execute a counter pattern test in order to detect a short open input signal and/or a failure in counting capability of the first microcontroller and a second microcontroller including a third hardware counter, a fourth hardware counter, a second storage device that stores a second firmware algorithm code. The first and second firmware algorithm codes are configured to resynchronize and restore respectively a first counter or a second counter after the counter pattern test and are configured to detect an offset and adjust during a resynchronization process to account for the offset such that to successfully resynchronize two separate resynchronization algorithm codes are used depending on an input frequency of counter signals input to four hardware counters.