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I have two questions regarding (ARM 64bit) tablet/smartphone:

1. Can I overwrite the flash memory of an Android Tablet/smartphone without rooting it?

2. Can I backup the contents of the flash memory? I've read some PROMMers can do that.

Greetings
Peter

PeterX wrote:I have two questions regarding (ARM 64bit) tablet/smartphone:

1. Can I overwrite the flash memory of an Android Tablet/smartphone without rooting it?

2. Can I backup the contents of the flash memory? I've read some PROMMers can do that.

Greetings
Peter

In general, no. Booting non-official ROMs, including alternative recovery like CWM or TWRP, tend to require rooting to allow access to the FLASH and bootloader partitions.

It's frankly a shocking state of affairs, I suppose sort of mitigated by the fact it does make it very difficult for malware to be installed in the system software as well (that of course doesn't prevent malware apps being installed, but they're easy to wipe.) But any semblance of added security looks pretty thin when you're left with a phone with old, vulnerable system installation that cannot be updated because the phone has been abandoned by the manufacturer.

thewrongchristian wrote:

PeterX wrote:I have two questions regarding (ARM 64bit) tablet/smartphone:

1. Can I overwrite the flash memory of an Android Tablet/smartphone without rooting it?

2. Can I backup the contents of the flash memory? I've read some PROMMers can do that.

Greetings
Peter

In general, no. Booting non-official ROMs, including alternative recovery like CWM or TWRP, tend to require rooting to allow access to the FLASH and bootloader partitions.

Aww, what a pity! There goes my plan of easily tinkering with my Android devices... So rooting is the way to go...

Any chance that I can open the device and grab the Flash chip and put it in a PROM writing device?

Greetings
Peter

PeterX wrote:Any chance that I can open the device and grab the Flash chip and put it in a PROM writing device?

It's possible, but not easy: you'd need to desolder the chip.

Octocontrabass wrote:

PeterX wrote:Any chance that I can open the device and grab the Flash chip and put it in a PROM writing device?

It's possible, but not easy: you'd need to desolder the chip.

Ah, thanks, I overlooked that. And if it is surface-mounted it probably will be difficult...

Greetings
Peter

Octocontrabass wrote:

PeterX wrote:Any chance that I can open the device and grab the Flash chip and put it in a PROM writing device?

It's possible, but not easy: you'd need to desolder the chip.

Plus it's probably a BGA eMMC with tiny solder pads designed to be used with high precision pick and place robot manufacturing. I don't even know if there is a standard connector layout, making the prospect of standard writing devices remote (if not prohibitively expensive), but it certainly won't be plain FLASH PROM.

thewrongchristian wrote:

Octocontrabass wrote:

PeterX wrote:Any chance that I can open the device and grab the Flash chip and put it in a PROM writing device?

It's possible, but not easy: you'd need to desolder the chip.

Plus it's probably a BGA eMMC with tiny solder pads designed to be used with high precision pick and place robot manufacturing. I don't even know if there is a standard connector layout, making the prospect of standard writing devices remote (if not prohibitively expensive), but it certainly won't be plain FLASH PROM.

Thanks for the info, that is more of the bad news...

Greetings
Peter

PeterX wrote: Thanks for the info, that is more of the bad news...

Greetings
Peter

Good news for you:

You can get a dev kit. It will have much better connectivity for debugging and no need to 'press power button 10 s to reset'. Complete with support packages, documentations and example drivers.

If you don't need the latest SOC and touchscreen (the boards usually have HDMI and USB so you can use PC peripherals with it) you can save quite a bit of $$$ and get one much cheaper than a retail product phone/tablet.