Quadrature Decoder (TCPWM_QuadDec_PDL)

• 16- or 32-bit Counter
• Counter Resolution of x1, x2, and x4 the frequency of phiA and phiB inputs
• Index Input to determine absolute position
• Peripheral Driver Library (PDL) Component (PDL Application Programming Interface (API) only)

General Description

The TCPWM_QuadDec_PDL Component is a graphical configuration entity built on top of the cy_tcpwm driver available in the PDL. It allows schematic-based connections and hardware configuration as defined by the Component Configure dialog.

The TCPWM_QuadDec_PDL Component gives you the ability to count transitions on a pair of digital signals. The signals are typically provided by a speed/position feedback system mounted on a motor or trackball.

The signals, typically called phiA and phiB, are positioned 90 degrees out of phase, which results in a Gray code output. A Gray code is a sequence where only one bit changes on each count. This is essential to avoid glitches. It also allows detection of direction and relative position. A third optional signal, named Index, is used as a reference to establish an absolute position once per rotation.