What's the difference between a "hard reset" and powering IPhone 3G off?
This is a simple question but I am not sure if anybody knows the real difference. Hopefully, somebody does.
What is the difference between what is referred to as a "hard reset", which is done by holding down both the sleep/off button and the home button until the Logo appears and shutting off the phone by holding only the sleep/power button until it shuts off?
Holding the wake/sleep button and home button should not bring you to the Apple logo. The logo only appears when you power the iPhone on! You should also be prompted to power off when you do the hard reset.
I have never tryed to hold the buttons until the logo appears.
Don't do it then. You obviously don't want to. I've told you in two separate threads what they do. Hard reset will not help YOUR phone if it's working correctly. That being said, it doesn't necessarily hurt it either.
Thank you. I was looking for something a little more technical like when you power it off it just puts most hardware into a sleep or low power state where as a hard reset actually resets and/or removes power to most/all hardware.
Thanks again for your responses.
Just for reference, the term "powering off" when speaking of cell phones usually means putting the hardware into a low power state but does not reset the devices. Doing a "hard reset" on any computer type device including cell phones usually means actually reseting ALL the hardware on the device.
A hard reset is a good idea after you do a sync/backup. It's a good idea if you start having some small issue like lag. It will shut all apps that you did not properly shut down by holding the home button down until the screen goes blank to exit all apps. you do not shut apps down properly it will cause memory leagage that will cause the lag.
Don't be afraid to do a hard reset. It's like restarting your computer it's a good thing to do some times. iPhones are small computers, and like people computers need to clear their minds and be left alone for a moment.
I can understand your frustration in people just not wanting to listen to your advise that you know works, but part of teaching a person is remaining stead fast and calm. I see you out here helpin' just keep on truckin man. let their reluctance roll off your back. In the end it's only them that they hurt. Unless you count the bandwith they use up and cause people to die because 911 can't answer cals cuz the bandwith is all used up! 😉
I was under the impression that a hard reset does exactly what turning the phone off then on again does, but is useful when your phone is glitched, frozen, etc.
geauxiacerx - I am not sure what your point is here, but I just asked a simple question, and although I will admit that your response of - Posted: Aug 18, 2008 8:22 PM was helpful, it is obvious to me that you don't know what the technical difference is, and neither does the other respondent who did all the complaining. No one asked him to respond more than once to my question.
I made it clear, in what was to be my last post in this thread, before you made your non-useful and unnecessary comments, that the difference technically is that a hard reset actually resets ALL the hardware and thus will cause it all to restart whereas "powering off" just puts many of the devices into a lower power state but does not actually reset any devices. So when you turn it back on, it just "wakes up" but has not actually been reset (did not go through all it's normal boot sequences when woke up).
It is like putting your computer to sleep (powering off the IPhone 3G) and pushing the reset button on your computer (doing a hard reset on the IPhone 3G). What I was looking for was specifics about the IPhone 3G, a device I am not that familiar with, that might be different from the norm.
Dr Sly; Thank you for your response. To better help anyone who is curious about this, most every device within the IPhone 3G, the CPU, radios, some amps, etc. have a pin on them that is called "reset". What this pin does is when it is driven active (to ground in most cases) all the internals (registers) within the device get set back to their default values when they were first powered up or first programmed. Many devices also have the capability to run at lower voltages and to have their clocks shut off to save power.
A "hard reset" resets most all the hardware devices (CPU, GPU, Raidos, etc.) to their default states and the CPU starts code execution at it's default startup address. When you power the IPhone 3G "off", by holding only the sleep/power button, it causes many of the devices to have their voltages lowered and their clocks shut off, which saves power. When you turn the phone back on, they simply have their voltages raised to normal operating levels, their clocks turned back on, and they are in the same state they were in before you held the sleep/off button.
So, the difference is that holding the sleep/power button only reduces the power the devices use, and when powered back on the phone is in the same state as it was when you powered it off. This is similar to what is called suspend to ram, which is supported in most laptops today. When you hold down both the sleep/off button and the home button this cause all devices to be reset and to start up from their default states. Any volatile memory will be lost in this case. This is what prompted my question.
On your computer, there's no difference between pushing the reset button or pushing the power button. The startup process is the same.
The iphone may be a computer, but it's also connected to the cellular network. And who can say for certain how the cellular network handles hard resets vs. power on state. I'd be more confident of powering the iphone off for a while then turning it on again. That way i know for SURE that not only has the iphone been properly reset, but any cellular connection issues have been restarted/refreshed as well.
A "hard reset" resets most all the hardware devices (CPU, GPU, Raidos, etc.) to their default states and the CPU starts code execution at it's default startup address. When you power the IPhone 3G "off", by holding only the sleep/power button, it causes many of the devices to have their voltages lowered and their clocks shut off, which saves power. When you turn the phone back on, they simply have their voltages raised to normal operating levels, their clocks turned back on, and they are in the same state they were in before you held the sleep/off button.
So, the difference is that holding the sleep/power button only reduces the power the devices use, and when powered back on the phone is in the same state as it was when you powered it off. This is similar to what is called suspend to ram, which is supported in most laptops today. When you hold down both the sleep/off button and the home button this cause all devices to be reset and to start up from their default states. Any volatile memory will be lost in this case.
rimshaker; You make some good points regarding the cell network and how it reacts to the phone connecting to the network.
As to your statement here - "On your computer, there's no difference between pushing the reset button or pushing the power button. The startup process is the same.", this is not completely true. When you push the reset button the BIOS knows that power has not been removed and skips setup stuff it does when power is lost because there is no need to re-execute it. When you power the computer completely off, the BIOS runs through the entire initialization. I have worked on issues on new designs that only occurred with one but not the other. There is a difference.
If you are more comfortable with being sure that "...the iphone has been properly reset....", then you want to do a hard reset. Powering the phone down by holding only the sleep/off button for 6 seconds likely does not reset anything.
I need some further clarification. There are 3 ways to shut the phone off:
1. Tap the top button. Phone is still on, screen is off.
2. Press and hold top button. Red slider appears. Slide it, phone powers off.
3. Press and hold top button and home button simultaneously. Red slider appears. Slide it, phone powers off.
When you are all talking about "hard reset" vs. "powering off" are you talking about #2 vs. #3 or are #2 and #3 the same thing and you're comparing #1 to #2/3?
Just want to know if there are three degress of offness or just two. Want to know if getting the red slider is the same whether you press and hold the top button or press and hold top/home simultaneously.
