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MP5,1: Return of the microcodes (MP51.0089.B00) **OBSOLETE**

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Cecco said:
Flashing is ways cheaper than buying a replacement mobo,
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Not necessary.

There are more than one member here got a whole used cMP. Extract the logic board. Fix the cMP. Sell the remaining parts. And end up get the logic board replacement for free / very little cost (or even earn some money).

It just depends on how you do it.

Cecco said:
I've seen your post already. But you do not know what exactly died on your mobo. Could as well been a corrupted bootROM. By replacing your mobo you got a new bootROM as well that would have fixed it.
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It's hard to believe that a working cMP will suddenly has a corrupted BootROM. Both Synchro3 and my case are similar. After a force shutdown, the cMP never come back. In my case, I command a reboot to Windows, but it didn't reboot after few minutes. I have no idea if already finish the shutdown, but no boot, to not shutdown yet. So, not 100% sure if that's same as Synchro3's case. But end up, I of course performed a force shutdown because the cMP didn't reboot to Windows as expected.

If fact, your case is very very similar to ours. You didn't perform anything firmware related (your GPU can't even perform any firmware flashing). It's just a normal OS update. But the cMP didn't reboot as expected, then you performed a force shutdown, then the cMP never boot again.

I really wish you can successfully recover your cMP by re-flashing the BootROM. If you make it. Then AFAIK, you are the very first one to prove that the cMP can suddenly has the BootROM corrupted with no apparent reason. And a force flash may able to recover this kind of sudden dead logic board.
 
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MisterAndrew said:
2 dead Mac Pros recently from forced shutdown?
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3, Cecco, Synchro3, and me.

But TBH, force shutdown may be totally unrelated. It exists in all 3 cases because it's a must have action.

When the Mac has no response for a long time after re-boot / shutdown. The only action can do is force shutdown. We can never know if the cMP is failed before the force shutdown, or the force shutdown kill the cMP.
 
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h9826790 said:
I suspect that's nothing to do with force shutdown, but just some electronics reach the end of their life span.
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My thoughts too... I recently had a harddrive fail during an upgrade in the High Sierra cycle. It wasn’t even in use, it was a spare scratch drive. All was fine, then the reboot from the upgrade (warm boot) and poof, drives was dead.

Did the upgrade cause it? No! It was just at the point of failure during same time period.

BTW, the drive died after 18 Years to the month..
 
crjackson2134 said:
Scary to think that someone with your skill and knowledge got bricked with an EFI Mod update. It gives me pause on doing my own down the road. I wouldn't have the skillset needed to recover from this on my own.

I think I'll stick with booting from my SSUBX/SATA and leaving the higher speed NVME for storage only.
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I know exactly what I did wrong, minutes after the brick I've found that I did a mistake editing the BootROM. I've added when I needed to replace same bytes and the edited BootROM was bigger than the original. Always check the final size before updating your BootROM!

I was awake for almost 26h when I was testing the new BootROMs and made that stupid mistake. Details are crucial, don't do this type of thing without sleep. =)
 
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tsialex said:
I know exactly what I did wrong, minutes after the brick I've found that I did I mistake editing the BootROM. I've added when I needed to replace same bytes and the edited BootROM was bigger than the original. Always check the final size before updating your BootROM!

I was awake for almost 26h when I was testing the new BootROMs and made that stupid mistake. Details are crucial, don't do this type of thing without sleep. =)
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Yes, but for a Pro such as yourself to make such an error, imagine how worrisome it is for a novice.
 
crjackson2134 said:
Yes, but for a Pro such as yourself to make such an error, imagine how worrisome it is for a novice.
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Yep, but my bricked Mac Pro had the EXACT same symptoms of @Cecco, to the letter.

Btw, I'm not a pro, I just work on the field. =)

One other thing, reading the data sheet of the SPI Flash used on my Mac Pro, I've noticed that the temperature range is 85º - to me this is insufficient since it's exactly below the GPU, next to the PCIe Power B. Maybe Apple needed to use one with 105º grade on that spot.

I've repaired a lot of Macs from family/friends over the years and one of the things I encounter is corrupted BootROMs. Apple don't use a battery backed RAM to store configurations like on PCs, all settings are saved on the SPI Flash, so I suspect things got corrupted sometimes. Change your Wi-Fi password, Back to My Mac update the SPI Flash. Change your boot disk, SPI flash updated. Go to Windows, SPI Flash updated. Clear your NVRAM, SPI flash updated.

The SPI flash is not a NAND like we use today on SSDs, the endurance is a lot lower, some have 4,000, others 10,000 writes, military ones with 100,000. Working on the limit of the temperature, maybe some 4k sector writes (you have to write a sector to change one bit) get garbled, and other information is corrupted on the writing.
 
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crjackson2134 said:
So can we get a military grade chip, flash the Mac firmware, and replace the original?
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I did re-use mine, since I didn't have a 32Mbit with greater temperature range. I tested it with various cycles of full write/erase on my Needhams EMP31 programmer. If my BootROM ever get corrupted again, I'll get one SPI flash with 105º, for sure.
[doublepost=1532406533][/doublepost]
h9826790 said:
This explained what happened in my case.
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If you still have your old logic board and has a Raspberry Pi, get a Pomona clip (I suspect that it's a lot cheaper for you in HK than for me here on the land that everything imported costs the triple, Brazil) and flash it with your saved working dump, could be that your BootROM got corrupted.
[doublepost=1532406665][/doublepost]
h9826790 said:
This explained what happened in my case.
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You can use even a dump from the new board, later you can change SSN, OrderNumberSKU and LBSN.
 
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tsialex said:
I did re-use mine, since I didn't have a 32Mbit with greater temperature range. I tested it with various cycles of full write/erase on my Needhams EMP31 programmer. If my BootROM ever get corrupted again, I'll get one SPI flash with 105º, for sure.
[doublepost=1532406533][/doublepost]

If you still have your old logic board and has a Raspberry Pi, get a Pomona clip (I suspect that it's a lot cheaper for you in HK than for me here on the land that everything imported costs the triple, Brazil) and flash it with your saved working dump, could be that your BootROM got corrupted.
[doublepost=1532406665][/doublepost]
You can use even a dump from the new board, later you can change SSN, OrderNumberSKU and LBSN.
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Thanks for the suggestion, but that's beyond my skill level at this moment. May be when I want to have some fun, I will do some study try this.
 
h9826790 said:
Thanks for the suggestion, but that's beyond my skill level at this moment. May be when I want to have some fun, I will do some study try this.
Click to expand...
The more troublesome part is to get the board out of the Mac and remove the SPI flash, the programming part is simple.

I never did the on board flashing on a Mac Pro, but did several times on Mac minis upgrading from 1,1 to 2,1 firmware. With a 3V3 bench power supply to compensate the board components drain, like I suggested to @Cecco, you will get it done without having to use a hot air rework station, like I did on my Mac Pro.
 
MisterAndrew said:
It's super unfortunate, but at least it can be fixed. Even a brand new board isn't too terribly expensive.
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For people in the US, it's a lot more cost effective, no doubt. For the unfortunate ones who live on parts of the globe where everything costs double/triple when added shipping/taxes, we have to try to repair first. =(
 
Sharing info from an eBay vendor selling flash gear for flashing efi from the diagnostic port. The same should apply using a Pomona clip.

90582372-68B1-4136-BD4F-848F77A805C0.jpeg
 
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@Cecco @Synchro3 @h9826790 what firmware version were you all running when your cMP failed?
Might it have been the same for all three of you?

Also, were you all 4,1–>5,1 cMPs?
 
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handheldgames said:
This may not have the correct connector. You need one from the 2009/2010 MacBook Pro. It’s the same as the one near little frank.

[NEW] EFI-ROM Converting board for Apple MacBook J6100 SPI-ROM EFI ROM https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/323225409462
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First, thanks for bringing the external programmer for J6100, I've only knew the chipmunk ones.

Like I suggested before on the thread, inject 3V3 on VDD, GND on VSS and use the Pomona clip + Pi with flashrom.

BTW, you don't need a bench variable power supply to do this, you can use 3V3 from a ATX PC power supply. If I ever need to do this again on a high drain device, I will power the Pi and the SPI flash from the ATX power supply, to have common ground on everything. It'll be a lot easier than desoldering, flashing on my external programmer and soldering again, plus not needing to remove the logic board, just the processor cage.
 
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tsialex said:
Btw, I'm not a pro, I just work on the field. =)

The SPI flash is not a NAND like we use today on SSDs, the endurance is a lot lower, some have 4,000, others 10,000 writes, military ones with 100,000. Working on the limit of the temperature, maybe some 4k sector writes (you have to write a sector to change one bit) get garbled, and other information is corrupted on the writing.
Click to expand...

Comparatively speaking, I still consider you to be in a Pro skillset category.

Since you know the exact chip that Apple used in these fragile little things, how many write cycles are they good for? I guess I should start avoiding the changes made by the startup disk manager, and only use the option boot picker. This may save me some write cycles.

I wish Apple used a bootloader like GRUB. It’s ugly, but at least it won’t brick your machine.
 
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