Yesterday I was at Global Components doing the Pyra prototype production run.
I already posted some things at Twitter and did post updates at the forums, but in case you missed it, here is the summary.
First up, what are we expecting from this pre-production run? -------------------------------------------------------------
If all goes well, we will have working Mainboards, working Display Boards and working CPU board. A lot has been tested before with manually populated prototypes, so in theory they should be functional, but we also do this to find issues upfront that could cause problems with the mass production.
Though we can test the basic functions of all the boards here with the equipment Nikolaus has with him, we cannot assemble a unit and test it right away here. It will need some kernel changes and recompilation, but you can be sure Nikolaus will do that within the next few days so that we should have a fully working setup this week.
Where and how will it be produced? ----------------------------------
Well, this is where I post a lot of photos from the production site, so I advise you to check the link at the bottom of this mailing to actually see them.
The production line where everything will be produced. The first machine with the dark cover puts the solder paste onto the PCBs. Then the boards move on to two Siemens Siplace machines which automatically populate the boards. They will then be put into a steam solder machine and that's it.
You can only populate and produce one side at once, so the mainboards will need to go through the machines two times.
The pick- and place machine picks up parts and puts them on the PCB.
Most parts come on rolls where as some come on trays like the Cinterion 4G modules.
First, we populated the mainboard: ----------------------------------
The first side of the mainboard was populated without any major issues. The frame where the PCBs are in need to be strenghtened a bit, but that's not a big deal. Good thing we found that out here, as it would've caused delays (and costs) for the mass production run
Populating the second side of the PCB caused a bit of trouble. The PCBs are too heavy and hang down in the middle. This is the same issue as mentioned above: The frame needs to be better to support the PCBs. No big change though. The PCBs has some parts which are VERY close to each other. Combine those two things and the danger exists that they make a short circuit.
That's why a lot on this side of the PCB has actually been populated by hand. Of course, that's not feasible for mass production. Nikolaus will move some parts a bit so that aren't that close to each other and with the improved frame around the PCBs, everything will be fine.
That is actually not an issue we got here, that's the reason you do a pre-production run: To find out such things and be able to fix and tweak them before the real mass production will start.
Using a microscope, we checked that all parts were sitting fine and no accidental short-circuits happened. So far, it looks pretty good.
Nikolaus also connected a USB power source to the Micro-USB port which caused all the Power LED to blink (which means that the battery controller didn't find a battery but is working). One PCB didn't blink, but the cause was a simple fix: A resistor hasn't been placed properly.
After that, we did some more thorough tests of the mainboard, connecting Nikolaus' modified CPU PCB on top of it. Some i2cdetect-tests show that a lot of things are working, but we haven't tested all of them yet, that's a job for Nikolaus for the next few days.
BTW: The keymat in the dark looks beautiful, and that's still with the old keymat (and therefore it will be even better with the updated keymat):
Let's head on to the CPU boards... ----------------------------------
Unfortunately, we weren't that lucky with the CPU board. After they had been soldered, the parts had moved around. So yep, none of those first six produced boards is going to work, sadly.
One day has passed and Global Components found the issue with the swimming parts (it was a fault in one of the datasheets). Nikolaus already grabbed one of the CPU boards which should work fine (they have xrayed it) and is now trying to get it to work (it needs a slightly modified bootloader). I'll let you know once he got it booting. And we are lucky: The PCB manufacturer produced more bare PCBs than we needed (in case some were broken) and they all passed the electrical test, so we get some more CPU PCBs. No need to manually rework all of the old one!
The display PCBs will also be produced this week, but these are the simplest ones, so nothing to worry about here.
By the way, the new keymats were finished 12 days earlier than planned and are already on the way to me.
The last missing piece now is the case, and I'm currently finding out when that will be finished so I can book a flight to Greece.
I'll keep you posted!
Want to leave feedback or see the pretty pictures? Visit: https://boards.openpandora.org/topic/5600322-prototype-production-run