> > often adding an extra frame or 2 of lag in the process from what I can tell, much > > like you get with modern machines and all the layers of code signals need to go > > through before they actually hit the game. > > The MCU usually reads the controls at vblank, and the main game fetches them from the > shared RAM at the same time, so there's always 1 frame of lag added in that scheme.
I thought some of the ones with analog inputs sampled the analog inputs over 2 frames on the MCU, writing all the data (including digital inputs) to shared ram with a delay as a result rather than allowing the game code to poll the input lines on the standard inputs directly.
Could be wrong tho, sure I remember somebody pulling apart the MCU code for one of the games and saying that tho.
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