The Signal Acquisition System of the Grating Displacement Sensor Based on CPLD and USB Interface

According to the rectangular pulse signal of the grating displacement sensor, the system realized the displacement signal acquisition, through the grating signal processing and the computer interface. Signal acquisition system of the grating displacement sensor was composed of the grating signal processing circuit based on CPLD and USB interface communication controlled by MCU. Subdivision and direction-judgment module, counter module, interface module, all of which were included in the grating signal processing circuit and the design methods were introduced in detail. Using CPLD chip EPM7128 realized grating signal processing. Adopting USB interface chip CY7C68013, data transmission between CPLD and host computer was carried out. The signal acquisition system of the grating displacement sensor shows the displacement of the grating displacement sensor through the computer application program interface, it has small volume and it works stably and reliably. The range of this system is 0-200mm and the resolution is 5μm.