Can someone explain to me what the “sanity delay” at the beginning of the examples is for?
If the sketch allows excessive consumption of power by the leds, you starve the microcontroller and even reprogramming can be a challenge. The delay helps prevent that.
Thank you for the quick response. So if I power both independently I don’t have to worry about that?
I was also wondering about that ‘sanity delay’ but never bothered to ask for an explanation. So i most often just left it there while having to wait seconds for my sketch to eventually show some life !
Now that answer still does not explain it for me.
That sanity delay is always found at the very beginning of the Setup() function that gets executed immediately when the voltage has ramped-up sufficiently to power the microcontroller.
At that point the micro controller is sufficiently ‘awake’ to properly execute all the instructions associated with a ‘delay’ (not much I will admit but still… ) why is it not ready to execute any other instructions even assuming LEDS or any other device is drawing the PSU’s rated maximum current on power-up !?
Wouldn’t that only cause the voltage to have ramped-up a bit slower to the point where the microcontroller is operational ?
It’s what happens after the setup function (i.e. Turning all LEDs on full white) that can starve the microcontroller.
The delay is there to give you ample time to reprogram the microcontroller, before it turns on the LEDs.
Hi @Christopher_Smolinsk ,
OK, now I think I got it but… It has actually convinced me that I will remove it from all my sketches from now on !
If somehow, I do get that situation of a microcontroller ‘starving’ for power, I would simply correct the power problem before resetting the microcontroller.
either by disconnecting the load or substituting an adequate power source for the load that is there !
I prefer that to waiting seconds before i see life from my setup every time I re-program or power-up my micro controlled things !!