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Your TV may not recognize the C64's video signal. The C64 video signal is, technically, 240p. Some chips have issues with this. This can also be observed with quite a few Video->HDMI converters. DIN<->RCA adapters come in different configurations. The DIN standard always has ground on pin 2 (the low middle pin - I will describe the pin assignment ...


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Most of the typical full color resolutions were based on 4:3 ratio - e.g., 640x480, 800x600, etc. - which matched the aspect ratio of broadcast television at the time. Using a 4:3 pixel ratio on a 4:3 display screen meant you had have nominally square pixels. Graphics routines, especially with limited RAM & CPU cycles, are a whole lot easier with square ...


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The PC boots in text mode, and on a VGA card the text mode indeed has a resolution of 720x400. As the text mode was the most used standard mode before GUI programs and operating systems were loaded, so it made sense to name the mode as 720x400. However, the monitor actually cannot know what the exact resolution is, because for example 320x200 graphics mode ...


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This is historically not uncommon at all. Before starting an Operating System and initializing a graphics mode, your PC operates in the simplest display mode available, 80x25 text mode. The original VGA 80 x 25 text mode (that is still supported by most modern graphics cards) has characters with a resolution of 9x16 pixels per character. This adds up to 80 ...


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The ideas behind: DRAM access takes place at every CPU cycle. Every other DRAM access (or slot) is for video (further differing between attribute and pixel reads), the rest slots are for CPU. In fact, CPU and video slots simply follow each other in a rigid sequence. As the M1 read signals are active for only 1.5 clocks, the Leningrad phases or 'aligns' each ...


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The second shift register is wired to provide a 4-cycle delay after the pixel data is loaded before it is displayed. This is presumably designed to allow the system enough time to load the corresponding attribute data into the pair of storage multiplexers labelled D30 and D31 after the pixels are fetched but before they start displaying; if it were missing, ...


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