When electronics powers up there's a slight delay in getting steam pressure up to supply all components wiv power. There be a problem if yer processor wakes up faster than yer ram memory. The processor may want to start using said ram whennit ain't ready. Circuits wiv many different steam pressures fer different components make it more complex. Not unusual to have plus and minus 3.3, 5, 10, 12 and 15vdc in more demanding circuits. Some have lower pressures of plus and minus 1.5 or 1.8vdc. Fings are made worse if the power supply is slow to wake up. The different voltages will be regulated seperate. Some will be up to pressure before others.
So how does they solve this? Components like ram memory, processors, flash memory, ard drives etc have a reset line. That signal can be high or low. When the reset is active, components sit ready waiting in reset for the reset line to switch to active. When it does they start wuking.
Yer typical processor circuit has a 'delay on' circuit. It does worrit says ont tin. Its a small circuit wiv a timer, used to create a delay to start the circuit wukking after steam pressure has built up. Typically 20 or 50 milly seconds. The ootput from the delay on circuit is connected to the reset line. The job of the delay on circuit is to hold the reset singal in reset, fer a small number of milly seconds, to allow steam pressure to build up in the rest of the circuit. Once complete, it changes the state of the reset line from high to low (or low to high depending on the logic) which triggers fings to start wuking. The processor will then start loading program code into its registers. Yer phooter is now starting to wuk.
Wots the difference between first powering a processor circuit up and resetting it? Nowt. When a processor circuit resets it triggers the delay on circuit to control the reset line. Fings like ram can quickly wipe themselfs during a reset. The processor will ferget where it is in the program and start from the beginning again when said reset line is released after the requested delay on, completes. After the delay on milly seconds delay timer completes its time delay, the reset line switches and fings start oft fresh again. In reality it dun't matter if ram is cleared. The processor uses a new page in its notepad each time its powered up to remember which memory address locations it uses to store fings to remember.
So resetting a phooter ain't no different to pulling the power oot, letting steam pressure drop, then applying power again. The only benefit to removing power is when fings like power supplies mess up. Current limit potection could kick in iffit can't regulate itself if one of the steam power volt rails hassits steam sucked oot quicker than normal due to high current demand when fings sometimes go wrong. Like during component failure.
