No EEPROM/flash device found.

Rickkap wrote: I'm having problems getting the Raspberry Pi and Rev 3 to communicate on some MacBook Air logic board. I'm able to read A1465 2013 and A1369 2011 but I can't read the following:

A1466 2012,2013,2014
Can someone tell me which pin they are leaving out either 3 or 7 or both and where the switch position is?

Also if someone could shed some light into why I am unable to read some logic board but I can others

Rick

The switch should be to the left if the SPI connectors are at the top. Be sure you have a fully charged battery also. The 1466 can be a bit touchy. I leave 3 and 7 connected.

Rickkap wrote:

CygnusX1 wrote: [quote="The switch should be to the left if the SPI connectors are at the top. .

Now I'm confused, I thought for 11" the switch is to the left and for 13" switch to the right!!!!!!

CygnusX1 wrote: [quote="Be sure you have a fully charged battery also. The 1466 can be a bit touchy. I leave 3 and 7 connected.

I thought you read the EEPROM without the battery connected!!!!!

Help !!!!!!!!!!!!!!!

This works!

The switch on the MBA clip changes the pinout configuration.

MBA Clip Pinout Configuration

Pin 1 of the chip (marked with a small dot) which is CS (Chip Select) goes to pin 24 on the Raspberry Pi.
Pin 2 of the chip which is MISO (Master In Slave Out) goes to pin 21 on the Raspberry Pi.
Pin 3 of the chip which is WP (Write Protect) goes to pin 17 on the Raspberry Pi.
Pin 4 of the chip which is GND (Ground) goes to pin 25 on the Raspberry Pi.
Pin 5 of the chip which is MOSI (Master Out Slave In) goes to pin 19 on the Raspberry Pi.
Pin 6 of the chip which is SCLK (Clock Speed) goes to pin 23 on the Raspberry Pi.
Pin 7 of the chip which is HOLD (Hold) goes to pin 17 in the Raspberry Pi.
Pin 8 of the chip which is VCC (Positive Supply Voltage) goes to pin 17 on the Raspberry Pi (3.3v)
I use a breadboard to gain more 3.3v out. I run the 3.3v from the PI to the breadboard that has a five pin header installed so I end up with extra 3.3v connections for the clip.

I use the above pinout configuration for models A1502 - A1466 - A1465 - A1425 with the switch to the left.

I use the same pinout configuration as above for models A1398 - A1369 - A1370 except I throw the switch to the right.

Some people don’t use the 3.3v for the WP and the HOLD. I use them all the time and never have any issues especially with model 1466 which requires the 3.3v on the WP and HOLD.

Then run your flashrom commands as normal.

Rickkap wrote: Hi CygnusX1

Quick question:

Do you have the battery connected?

Also do you connect directly from the EEPROM to the Pi via a breadboard, without an EFI Easy Flash clip?

Can you upload a photo for me to have a look at.

I can't understand why I'm able to read A1465 2013 and A1369 2011 but nothing else. I have been trying to read a A1466 2013 or 2012 but it keep coming up with No EEPROM/flash device found, yet if I unplug either of these and connect an A1369 it finds it straight away.

I did have problems with this when I first got the EFI Easy Flash clip and after wiggling it I finally got it to work. I've checked the clip and all the pins are connected.

Thanks for your help

Here is a picture and the battery is connected.

Rickkap wrote: Thanks for the photo.

I see you have pin 3 & 7 going to your breadboard and pin 8 going to the pi - which pin from the PI are you using to feed 3.3v to the breadboard?

You can use 1 or 15 i think it is.

Cyber16 wrote: I kind of cheat without a breadboard.
On the MBA easy flash pins I jumper VCC & Hold together with a few strands of copper wire then I slide on the leads.
Then that HOLD lead is nothing more than a loop going to the WP pin on the easy flash OR Pomona clip
Basically taking the 3.3v of vcc and sharing it with Hold & WP
Works every time so long as you have a good power supply, Done a bunch of Mid 2012 A1466 logic boards.
The power supply I use is a 10 watt ipad charger

You need to have a 5v 2amp power supply. I ordered the new Pi power supply that is 5.1v 2.5 amp.

I think with the 1466 models there are 2 things that can stand in your way.
1 - there is a Hirose connector similar to the Molex used in the MBA Easy Flash which has to be interfaced with very carefully.
2 - there are some components sometimes inline with the pins from the chip to the header. using a pull up/down resistor or a smoothing capacitor usually combats this.

It's not a problem, it's a limitation that couldn't be accounted for. The universal clip is universal, which means I accounted for it this time. You need to go to the flashrom site and look at the faq about known problems. They recommend what I have in 2. I will try to do a detailed write up soon though. All in all you need to find out if it's connection that is your issue.