AFA (Automatic Frequency Adaptation)

The Automatic Frequency Adaptation (AFA) section allows you to enable the advanced noise immunity algorithm. The automatic frequency adaptation routine continuously tracks the amount of noise that is on each sensor and chooses a new scan frequency intelligently to avoid noise frequency and its harmonics. The routine requires an 8-bit timer to precisely control the scanning frequency. Due to this requirement, mTouch will take ownership of the first available 8-bit timer module by default, if one is available when the automatic frequency adaptation routine is enabled.


The AFA requires extra Flash and RAM memory so this feature may not work with RAM limited controllers. If the AFA is disabled, the system will choose a random scan frequency every time.

For software CVD implementation only, the timer interrupt for the selected AFA timer must be enabled by the user.


You can always refer to the notification to check whether the timer interrupt should be enabled.

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