Slow down PCA9685 servo

You can use this to set a slew rate limit on a value, if that is what you are trying to do. This example limits the slew rate to 1 unit/second, sending intermediate values every 100 msec. Hopefully it is obvious from the code how to change the rate.
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This flow can be found at https://flows.nodered.org/flow/13c793620b6ec830ef610c13fd845bcb