Sync Signal Detector; 28.15.1 Overview - Renesas Hitachi H8S/2194 Series Hardware Manual

28.15

Sync Signal Detector

28.15.1 Overview

This block performs detection of the horizontal sync signal (Hsync) and vertical sync signal
(Vsync) from the composite sync signal (Csync), noise counting, and field detection.
It detects the horizontal and vertical sync signals by setting threshold in the register and based on
the servo clock (φs = fosc/2). Noise masking is possible during the detection of the horizontal
sync signals, and if any Hsync is missing, it can be supplemented. Also, if total volume of the
noise detected in one frame of Csync amounted over a specified volume, the detector generates a
noise detection interrupt.
Note: This circuit detects a pulse with a specific width set by the threshold register. It does not
classify or restore the sync signal to a formal one.
Rev. 2.0, 11/00, page 795 of 1037