GQ-4x4 - read and write from the M27C512 are not the same

[maurof650]

I am finding a problem with M27C512.

If I read it multiple times from the same eprom (powering the controller 9 volt as required), the bin files are identical and up to here is fine.

If I read a first eprom M27C512 and save the file .bin (64 Kbite); write the file .bin on an eprom and re-read the file.....comparing the two files with a hex editor but they differ by only one bit

With a second eprom instead of the file .bin differ totally.

I do not understand why

[guidotacco]

not write well,not alimemtarlo,write with the adapter?

[maurof650]

for the M27c512 is not required, the adapter and, in fact, I have written without.

[cinqueturbo]

Mauro I stumbled upon a short time ago and I solved with the sequence, erase, double, write, check..

[maurof650]

In the meantime, I tried again.
With the first eprom I ever the difference a bit.
With the second eprom now is the same.

The sequence that you indicated, what is? Also applies to the rewritable with the cancellation of uv?

[ugoboss]

the programmer does not need food, and if you have always the same difference on the same eprom can be that it is a problem of the same.

P.S. on these that have the window for the deletion not do erase, does not work, rather, check that it has been cancelled well, do the test before you write it if it is clean.

[maurof650]

The eprom that I used were new and just purchased. I also checked and gave me FFFFFFF so we can exclude this problem
I'll try to rewrite it after it is deleted.

[ugoboss]

do the test with the programmer if it is clean, you put on select the memory type and then press the control button on the left (it seems to me there is written in blanc, or something like that,now I don't have the programmer at hand) and tells you if it is clean or not.

[maurof650]

I don't see the button/option as you suggested.
See the screen

[maurof650]

the differences of the bits are at the line 00008AE0 column OR that 95 pass 90.
Can affect the map?

[cinqueturbo]

I don't see the button/option as you suggested.
See the screen



This is the sequence..
Not UV resistant..

[maurof650]

*cinqueturbo
ok..the check mark to erase (as I imagined) with the uv (and I think even with non-rewritable) is not required.
But the "double-write" is a simulation before writing, or other?

*ugoboss
I can't find the function that I have suggested, to check if the eprom is clean.

[ugoboss]

the function is "check vacuum"

[cinqueturbo]

*cinqueturbo
ok..the check mark to erase (as I imagined) with the uv (and I think even with non-rewritable) is not required.
But the "double-write" is a simulation before writing, or other?

*ugoboss
I can't find the function that I have suggested, to check if the eprom is clean.

The double writing, and simply double-write.. in practice, wrote two times to be certain that you do not leave anything unfinished.. on AM29F10 and almost obligatory