The OKY3431-2 Extension Module is a rotary encoder designed and manufactured by OKYSTAR. It is a small, low-cost, digital device that measures changes in the angular position or direction of a shaft or axle to generate pulse signals. It converts angular motion into a series of digital pulses based on the number of times the shaft has rotated, usually measured in increments of 100 pulses per revolution (ppr). This module features a contactless sensing mechanism and is designed to provide outputs in both “pulse width modulation” (PWM) and quadrature formats, and can be configured for up to 128 pulses per revolution (ppr). It also includes a temperature sensing element, giving it excellent temperature stability across a wide range of operating conditions. Additionally, it is completely immune to external magnetic fields and offers high EMI/RFI immunity. The OKY3431-2 is an affordable, reliable, and easy to use solution for rotary encoder application in digital control systems.