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Topic History of: a1502 emc2835 MX25L6473EZNI chip not found

Max. showing the last 6 posts - (Last post first)

Doni

7 years 1 month ago

a1502 emc2835 MX25L6473EZNI chip not found

keep on try in any power state, and try to press the power button for two second but dont let the mac power on, close the lid, i have the same model as you, and just sucesfully flashing last night.

mrcesco

7 years 3 months ago

a1502 emc2835 MX25L6473EZNI chip not found

reverendalc wrote: test resistance between the GPIO at the raspberry pi and the teeth of the test clip.

Following this thread www.ghostlyhaks.com/forum/apple-efi/720-no-eeprom-flash-device-found#5704 i tried to test the continuity with a DMM.

1° test on the board:
Placing the "black" probe lead on the 4th pin and the "red" probe lead on the 8th pin the value on the dmm changed from 1 to .004

2° test with the clip:
I connected the clip to the chip and then i placed the probes lead on the wires which correspond to the 4th and 8th pins but the value on the dmm didn't change.
So i presume the clip is not working.

Does what i said make sense? Thank you!!!

reverendalc

7 years 3 months ago

a1502 emc2835 MX25L6473EZNI chip not found

test resistance between the GPIO at the raspberry pi and the teeth of the test clip.

mrcesco

7 years 3 months ago

a1502 emc2835 MX25L6473EZNI chip not found

Hello, the position of the wires seems to be good but i have to test them with a DMM.
Also the SPI should be properly enabled but i'm going to search this "self-test" to try.
For the clip i think that will be the last purchase i'll do...
I'll get you back soon about all, Thank you.

reverendalc

7 years 3 months ago

a1502 emc2835 MX25L6473EZNI chip not found

also please use a DMM to make sure that all of your 3v3 wires are properly joined.

have you followed the blog on setting up your raspberry pi?

there's an SPI self-test you can commit.
additionally, i would recommend buying a genuine pomona 5250 clip as those knockoffs are prone to failure