On CPC, the The HSYNC and VSYNC signals are received from the [[CRTC]]. These signals are then modified by the Gate Array as C-HSYNC and C-VSYNC and then merged into a single CSYNC signal that will be sent to the display.
When CRTC HSYNC is active, the Gate Array immediately outputs the palette colour black. If the HSYNC is set to 14 characters then black will be output for 14µs.
