Wheel speed acquisition process (pr

Wheel speed acquisition process (program): For the ABS wheel speed signal acquisition and processing module, the main body of its software design is to generate an interrupt when the fourth event enters FIF0, enter the interrupt processing program, and interrupt the service program. Define registers related to interrupts, set variables and constants for data collection, etc.After the interrupt handler runs, it detects which channel triggered the event in sequence. If the channel triggers the event, it enters the triggered interrupt program and enters the interrupt self-program. It first determines whether it is the first interrupt. In the event register, exit the interrupt subroutine as the initial value of the event. If it is not, put the event in the event register 2, add 1 to the interrupt count register, and then calculate the difference between time t1 and t2, and store the difference in the register , Call the wheel speed processing subroutine, and then exit the program.Wheel speed processing steps: first determine the number of wheel pulses detected by the microcontroller in the event T, then calculate the actual measurement event Td, use the formula (4-7) to calculate the wheel speed, and read the previous time from the speed register Speed ​​value