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WAITPNE, "Wait for Pin(s) to Not Equal," is one of four wait commands (WAITCNT, WAITPEQ, WAITPNE, and WAITVID) used to pause execution of a cog until a condition is met. WAITPNE is the complimentary form of WAITPEQ; it pauses the cog until the value of Port's I/O pin states, bitwised-ANDed with Mask, does not match that of State.
When executed, WAITPNE activates special "wait" hardware in the cog that prevents the System Clock from causing further code execution within the cog until the moment the designated pin, or group of pins, does not equal the designated state(s). The wait hardware checks the I/O pins every System Clock cycle and the cog's power consumption is reduced by approximately 7/8ths during this time.
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