void cfOptimizeCycleTime()
{
	int cycletime = 40;

	// first sector MUST already be loaded into buffer

	// the algorithm is as follow:
	// first the cycletime is high, for slow access.
	// repeatedly set the cycletime smaller (for faster)
	// stop once the data doesn't match what you got for the first read.

	while(1)
	{
		cfReadSector(fat_buffer, 0);

		if(memcmp(fat_buffer, buffer, 512) != 0)
		{
			// newly read buffer differs from original! must be corrupted, slow back down
			cycletime += 5;
			cfSetCycleTime(cycletime);
			return;
		}
		// otherwise trim it down a bit
		cycletime -= 5;

		if(cycletime <= 5)
		{
			// never let it go below 5
			cfSetCycleTime(5);
			return;
		}
	}
}