cpu and ppu parallelism

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cpu and ppu parallelism
by on (#4009)
I don't really know how to phrase this question....but how parallel are the cpu and ppu?

Are their clocks synchronized or independent? In other words, on NTSC, CPU Cycle 1 = PPU Cycle 1, CPU 2 = PPU 4, etc. always in that pattern, or are they in sort of a race condition?

by on (#4011)
They are synchronized. Main system clock speed is 21.47Mhz.

CPU is 21.47Mhz / 12 = 1.789Mhz
PPU is 21.47Mhz / 8 = 2.68Mhz