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Gate Array

133 bytes added, 9 July
/* CSYNC signal */
* H06 counts the number of CRTC characters processed during an HSYNC. H06 is incremented by the Gate Array for each CRTC character when CRTC HSYNC is active. The Gate Array activates the C-HSYNC signal when H06 reaches 2, and changes its graphics mode if a change was pending. It deactivates this signal when H06 reaches 6.
* V26 counts the number of HSYNCs occuring during a VSYNC. V26 is incremented by the Gate Array when the CRTC signals an end of HSYNC. The Gate Array activates the C-VSYNC signal when V26 reaches 2 (and if VSYNC is active on ASIC/Pre-ASIC). It deactivates this signal when V26 reaches 6. After the 26th line has been processed, the Gate Array stops outputting the palette colour black.
 
If a CRTC VSYNC is activated again while V26 is still in progress, then V26 is reset to 0 and starts counting up again the HSYNCs.
The HSYNC signal from the CRTC is 0 when inactive and 1 when active. Same for VSYNC.
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