No, and even if you could you still wouldn't be able to "update" your 1.5+ to 1.0.

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what uf u changed the psp version to lets say .50? then it would run and 1.50 has kernal mode

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If it was possible we'd have a 1.0 downgrader.

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wouldnt there be a way to edit the psp since 1.50 has kernal mode will run everything like hombrew and everything
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yes but in theory it should be easier then a 2.00 to 1.50 right? what is haulting us with our progress we have all things and capabilites of making one am i right? i mean cmon where talking about 1.50 it has possiblities of downgrade. the reason why i want one is a custom firmware but i bet every1 wants that

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Did you not hear Homer, as he said you cannot make one, even if you did it would not run, not because it is 1.0, but because we cannot fake that kind of flash access. We do have full kernal and flash access but it doesnt change anything. If we flashed a 1.50 with 1.00, like in the past, would it work, The answer is no, because that flash is not made for that specific psp, the update makes it work with just your psp, if you took your 1.50 firmware and flashed it onto another 1.50 firmware it would probly brick, so plz listen to homer and understand it isnt possble..

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Here's the reason it won't work:

There is a hidden section of flash or bios (neather flash 1 nor flash 0) that keeps track of what f/w is installed and it is encrypted via sony's key(s) and your psp's unique id number (mac address, or something else, this is unknown too). When the update is ran, it changes this section of flash. Since this string is unique to every psp, a firmware won't run unless it detects this area to be correct. So, if you just copy the f/w 1.00 files, it will see that your signiture is wrong, and not boot.

BUT! It is possible to copy this area, upgrade to 1.5, then replace it. Hence, there is a "Downgrader" of sorts, but it will only work if your psp is already 1.0

P.S. This info is slightly "dumbed down" and has a few errors to it. Don't get mad at me, I'm only trying to help explain a more complex subject in simpler terms.

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i believe it was tried before and to when the psp was changed to ver <1.0 it f*cked up the psp. plus what is the use of a 1.0 psp as it doesn't have many features i.e. incompatible with some homebrew (devhook 0.41) 1.5 has best of both worlds

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