ZP100 not booting

thanks.
indeed, soldering the new nand would be the easiest part.
eventhough i would feel comfortable working with JTAG, getting the kernel stored in the new chip will be tricky since noone has it.



Replacing the NAND chip may be the easy part provided that you know how to work in removing and replacing chip on circuit board.

But the more challenging part is how to transfter/push firmware/software from/to the NAND chip.

Unless you have actual console device that Sonos Engineer use to do their internal development, re-programming the chips, it will be arduous task. Some have look into JTAG. But I don't know how successful/easy that can be

Haven't received the chip from China yet. Replacement, well, there's certainly a technique to replacing a 54 pin SMT chip.

upon further inspection, the chip, IS42S16800B-7T is a 16MB capacity only...and UART console show a 32M SDRAM config which mean there must be 2 chips. And this confirm by inspecting the board, there are 2 chips mount top/bottom joining together onto the board. So that mean we have to remove/replace both chips on top and bottom board!!!

Well, I have a couple of these ZP100s that do exactly as this thread describes... At first I was oh well, but after searching I found this forum. I now have a bus pirate on the way and I have a great hope that I'll get the ZPs working... Thanks to all that have made this information available... Hopefully, with a this great information The ZPs will be up running in short time once the bus pirate is received...

Wish me luck...

😉

Ok. So the one that I repaired is still going strong without issue. A buddy of mine bought two of them and one had a diag firmware.....got the newest firmware on that one easy. The second already was on the network. The one with Diag firmware will pair with the system but upon playing music will go orange light then white then orange. If you continue to hit the mute music will play for a second. The light means fault......is there a way to find the fault or clear it? The second unit will not pair at all. Any ideas?

Nobody has any idea's? I am going to take the one with faults completely down and reassemble this weekend. We will see if that makes any difference.

@soyuppy: If you've successfully upgraded to a non diagnostic firmware the post-boot console goes away. I'd check to see if you can add the unit to your network now as normal. As for pressing 'h' to get the help info, you need to do that immediately as the machine boots, otherwise it continues on to autoboot.

@mrmom: Do you get any errors during the attempted update, or does it just silently fail?

@racer26: I'd not imagine that the root password would be easy to recover. The machine is running Linux, so I bet it's salted. Also, if it is shared among different devices Sonos might not be super happy with someone recovering it. As for the RAM issue, I've a unit with similar symptoms as well. The RAM test fails on cold boot, however if you start the RAM test loop in the bootloader it starts to fail less and less as it warms up. My guess is that there is a temperature dependent failure in either the RAM chip, or in the solder joints attaching the chips to the board.

@ poshul: I am getting silent fails on all the devices I have left to convert.

@johnBCW: You are correct that those light patterns signal a fault. Unfortunately tracking down the fault is really tricky. Do you get the fault when playing music with no speakers attached? How about when attached to powered speakers?

@mrmom: I don't really have a good suggestion for you on that one. Make sure that the update command is correct, and that the image you are flashing is valid. Sorry.

So I finally received my RAM chip from China. Brought it in to the office where I have access to decently high-end solder rework gear.

As far as technique for replacing the RAM chip, I did the following:

Start with a new X-Acto blade, and carefully cut the 54 legs off of the RAM chip on the board. I tried to cut mostly in a plane parallel to the PCB, to avoid damaging the board, the pads, or the other nearby components. Once all 54 pins have been carefully cut, the body of the RAM chip (the ISSI IS42S16800A-7TL chip, in my case) will simply lift off the board, leaving behind its legs soldered to the pads.

Then, using a desoldering wick, carefully remove the pins and solder from the pads, taking great caution to not apply too much heat or force and delaminate the pads from the PCB.

Then, apply some flux to the pads, and carefully solder in the new chip.

I have never soldered SMT components this large before, but I do have a reasonable amount of experience with a soldering iron.

The unit I repaired was exhibiting prior to the repair with a symptom of fail to boot, flashing white light forever. Not responsive to factory resetting. The UART port was showing that it was failing the SDRAM check at the same address every time. Prior to the repair, I was able to get the unit to boot by manually issuing the command from the bootloader to ignore the SDRAM failure and boot anyway. The unit was otherwise operational.

I have not yet returned home to where I can test for full operation, but powering the unit up at the office seems to show it successfully autobooting and searching for my household to connect itself to.

Thanks for the tip on using X-acto blade.
so you replace both SDRAM chips that is mounted on both side of the boards?
Which chip did you get from e-bay? I see a lot but can't find one with exact match on the spec.

Huh. I hadn't noticed there was a second ISSI SDRAM chip on the bottom of the board. How about that.

I only changed the one on the top (ie. immediately adjacent to the large square microcontroller about 1.25" square).

This unit seems to be behaving now, so perhaps I got lucky. It was reporting its failures only at a single address, regardless of being warm or cold, so I suspect the RAM chip had gone bad at one particular address (on one of the two chips) and it seems I guessed correctly.

My other unit boots fine from a cold start, but when its warm it starts having RAM errors at a large number of seemingly random addresses. I should try reflowing the solder on all the pins of the two SDRAM chips and maybe that problem goes away.

This is the ebay part I purchased: http://www.ebay.ca/itm/271853110458?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

It seems that there are a number of compatible chips (I have two ZP100s and they had different chips in them from the factory, one had ISSI IS42S16800A-7TL, and the other had ISSI IS42S16800B-7TL).

Looking around online, it seems both of these have been obsoleted for some time. ISSI still sells a IS42S16800F-7TL which appears to have the same or very similar specs and is easily obtained from your favourite electronics suppliers. Mouser and Digikey both show stock for around $5/chip. I suspect it is a pin compatible upgrade, but YMMV.