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Last updated on Oct-18-2019 Download

Raster Time

Raster Time
by on (#192196)
How do you show frame raster time on a NES?
Re: Raster Time
by on (#192197)
Turn bit 0 of $2001 on (1) for 200-500 cycles, then turn it back off. This will make a gray stripe across the screen. To color the stripe, use one or more of bits 7, 6, and 5 of $2001.
Re: Raster Time
by on (#192200)
Or you can use any other mask bits of your choice, such as leftmost column background enable/disable.
Re: Raster Time
by on (#192201)
Nice, thanks.