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1* Pattern format for LED pattern trigger2 3The pattern is given by a series of tuples, of brightness and duration (ms).4The LED is expected to traverse the series and each brightness value for the5specified duration. Duration of 0 means brightness should immediately change to6new value, and writing malformed pattern deactivates any active one.7 81. For gradual dimming, the dimming interval now is set as 50 milliseconds. So9the tuple with duration less than dimming interval (50ms) is treated as a step10change of brightness, i.e. the subsequent brightness will be applied without11adding intervening dimming intervals.12 13The gradual dimming format of the software pattern values should be:14"brightness_1 duration_1 brightness_2 duration_2 brightness_3 duration_3 ...".15For example (using sysfs interface):16 17echo 0 1000 255 2000 > pattern18 19It will make the LED go gradually from zero-intensity to max (255) intensity in201000 milliseconds, then back to zero intensity in 2000 milliseconds:21 22LED brightness23 ^24255-| / \ / \ /25 | / \ / \ /26 | / \ / \ /27 | / \ / \ /28 0-| / \/ \/29 +---0----1----2----3----4----5----6------------> time (s)30 312. To make the LED go instantly from one brightness value to another, we should32use zero-time lengths (the brightness must be same as the previous tuple's). So33the format should be: "brightness_1 duration_1 brightness_1 0 brightness_234duration_2 brightness_2 0 ...".35For example (using sysfs interface):36 37echo 0 1000 0 0 255 2000 255 0 > pattern38 39It will make the LED stay off for one second, then stay at max brightness for40two seconds:41 42LED brightness43 ^44255-| +---------+ +---------+45 | | | | |46 | | | | |47 | | | | |48 0-| -----+ +----+ +----49 +---0----1----2----3----4----5----6------------> time (s)50