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CRTC

108 bytes added, 9 May
/* Tools about CRTC */
|2||Horizontal Sync Position ||00000000||46||When to start the HSync signal.
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|3||Horizontal and Vertical Sync Widths||VVVVHHHH||128+14||HSync pulse width in characters (0 means 16 only on some CRTCs. Needs to be at least 2 for Gate Array to change the video mode); VSync width in scan-lines (0 always means 16. Not present on all CRTCs, fixed to 16 lines on these).
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|4||Vertical Total (-1)||x0000000||38||Height of the screen, in characters.
|7||Vertical Sync Position||x0000000||30||When to start the VSync signal, in characters.
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|8||Interlace and Skew||xxxxxx00CCDDxxII||0||CC: Only in CRTC0. DD: Only in CRTCs 0, 3 and 4. 00: No interlace; 01: Interlace Sync Raster Scan Mode; 10: No Interlace; 11: Interlace Sync and Video Raster Scan Mode
|-
|9||Maximum Raster Address (aka Number of Scan Lines) (-1)||xxx00000||7||Maximum scan line address on CPC can hold between 0 and 7, higher values' upper bits are ignored
* [http://www.cpcwiki.eu/imgs/9/99/Elmar_Krieger-SPECIAL_EFFECTS.dsk some BASIC tools to detect CRTC types 0-1-2 and show some effects] by [[Elmar Krieger]] (DSK for Emulators)
* [[File:Shaker25Shaker26.dsk]] Shaker v2.5 - Suite of CRTC tests associated with the CPC CRTC compendium (many of them will not work correctly on emulators and that was the purpose of the tests, to help create more compatible emulation)
* [[File:Shaker addon.dsk]] Shaker Add-On (Pixel 1 Hard Scroll / Vertical Rupture all Crtc)
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