Why does the Nintendo MDS use the Clock frequency is 21.477khz for the CPU and PPU chips? Any reasons why the PPU chips don't like Spikes, Surges or switching noises on the +5vdc power rails?
Sorry or the late reply Wayne! I think the 21.477Mhz clock has to do with the boards generating NTSC video and not PAL. On the PAL versions the clock is different. And the PPU's are sensitive for the same reasons I think. I've tested the video output and it seems to be linear to the 5vdc. Maybe the internal die circuits are not rated for spikes or overvoltage's too. Also they are almost 40 years old and the physical parts are degraded just from time as well.
Why does the Nintendo MDS use the Clock frequency is 21.477khz for the CPU and PPU chips? Any reasons why the PPU chips don't like Spikes, Surges or switching noises on the +5vdc power rails?
Sorry or the late reply Wayne! I think the 21.477Mhz clock has to do with the boards generating NTSC video and not PAL. On the PAL versions the clock is different. And the PPU's are sensitive for the same reasons I think. I've tested the video output and it seems to be linear to the 5vdc. Maybe the internal die circuits are not rated for spikes or overvoltage's too. Also they are almost 40 years old and the physical parts are degraded just from time as well.