By synchronising to the display cycle any effect using the CRTC and Gate-Array is possible:
* [[Rasters|rasters ]] (Gate-Array)
* split-rasters (Gate-Array)
* diagonal-rasters (Gate-Array)
=== on the CPC+ ===
all the interrupts are generated by the [[ASIC ]] using the HSYNC signal from the CRTC.
Since the interrupts are based on the HSYNC signal from the CRTC, the position of the interrupt is directly related to the display cycle.
The time between the HSYNC and the interrupt request is always the same.
== Synchronising using interrupts on the CPC+ ==
On the CPC+, with the [[ASIC ]] special features enabled, we can use programmable raster interrupts, or DMA interrupts.
Programmable raster interrupts are the best, because we can define the exact scan-line we want the interrupt to trigger on. DMA interrupts are best if we want a regular repeating interrupt. e.g. every 8 scanlines.