(12-18-2019, 04:01 PM)hmuller Wrote: @tsys ,
I performed a physical clearance test of the PCB and it did not pass on my unit.
I took card stock and built it up (including scotch tape) to a 3.0 mm height, creating a test dummy. The rectangular dimensions of the test dummy were approximately the same width and length of the PCB (14.6 mm x 7.8 mm). I placed the dummy over the site it would be installed, over the audio amplifiers. Then the top surface was coated lightly with black pastel. A strip of white Post It note (with adhesive) 0.1 mm thick was stuck to the bottom magnesium case over the site the PCB would be over.
The combined height of the Post It note and the test dummy is 3.1 mm. This is the same height as the PCB (1.6 mm) combined with the height of the tallest component, L1, the inductor (1.5 mm). Note that the full height of the dummy extends to the full face of the rectangle, and not the surface area of the top of the inductor which is indeed smaller.
Unfortunately the test dummy created a full impression on the Post It note indicating there is little or no clearance for the regulator board in my particular unit. As there are bound to be variations between units, you may find this is not an issue with your unit.
But I may have a solution which may work but it will require a slightly different design. I will share the details later. I have not been in a rush, as I have to spend about $200 USD on equipment to do the actual PCB rework, aside from the board manufacture costs.
Oh wow, thanks for the extensive testing! I didn't got through that lengths to ensure it does actually fit since I do have all the equipment to just build and try it once the PCBs arrive. I don't think this is a solution many people will implement though. When shooting for something that is less janky one should probably just add a step-up to the M.2 adapter board.
(12-19-2019, 08:22 AM)tsys Wrote: ...
When shooting for something that is less janky one should probably just add a step-up to the M.2 adapter board. Yes, please  .
Knowing what we know now, we should be able to include multiple fixes.
For example, since the M.2 adapter board has a M.2 connector that sticks up, perhaps we should re-design it facing down. Then use a nylon standoff for the other end. Sometimes looking at a problem fresh may come up with a better solution.
Of course, I've not had a need to open my Pinebook Pro yet... so maybe mounting it upside down is un-workable.
After my ANSI PBP comes, I will feel more inclined to open up my ISO PBP.
--
Arwen Evenstar
Princess of Rivendale
(11-22-2019, 11:50 AM)hmuller Wrote: (11-21-2019, 07:49 PM)tsys Wrote: I'm in general somewhat puzzled about how the Pinebook Pro is supposed to stay operational when the battery is low. The discharge cutoff voltage of the battery is specified as 2.75 V. However U3 is just a step-down regulator. Thus it won't be able to maintain VCC3V3_SYS at 3.3 V once the battery discharges below 3.3 V.
That's a great observation. I suspect the 2.75 V is specified to keep it in U3's operational range. With that info, it's prudent to monitor battery voltage while on battery as system behavior may be abnormal below 3.3 V.
I am waiting on the replacement M.2 PCIe NVMe adapter before I install one. I will circle back when I have and share observations. I have my eye on the MyDigitalSSD SBXe, as it is cheap and has an "active power" rating of 3 W with an operating voltage of 3.3 V +/- 5%. FYIW I am running with MyDigitalSSD SBXe 480 as my file system, with boot on the emmc. (I used a hacksaw to "improve" the adapter) The drive seems to have average performance accoding to my initial phoronix disk benchmark testing.
I am able to boot the system with battery at 4%--I haven't tried with it any lower, since I normally would have the machine shutdown at 5%.
I have a rockpro64 on which I am playing with mainline u-boot with TSYS's atf patch (boot on SD or emmc, file system on Samsung 981) I'd love to get that going on this device, too, even if it can't yet boot the nvme directly, since the system seems to boot more quickly.
(12-24-2019, 01:27 PM)belfastraven Wrote: FYIW I am running with MyDigitalSSD SBXe 480 as my file system, with boot on the emmc. (I used a hacksaw to "improve" the adapter) The drive seems to have average performance accoding to my initial phoronix disk benchmark testing.
I am able to boot the system with battery at 4%--I haven't tried with it any lower, since I normally would have the machine shutdown at 5%.
I have a rockpro64 on which I am playing with mainline u-boot with TSYS's atf patch (boot on SD or emmc, file system on Samsung 981) I'd love to get that going on this device, too, even if it can't yet boot the nvme directly, since the system seems to boot more quickly.
That's great to 'hear'! @ zaius will be happy to add that to his SSD data. Once they send out the corrected adapters I look forward to installing it.
12-26-2019, 09:41 AM
(This post was last modified: 12-26-2019, 11:37 AM by as400.)
It looks to me like there are problems with NVMe disks that are heavily cached with DRAM memory which uses a lot of power.
MyDigitalSSD SBXe doesn't have any form of DRAM cache onboard. Maybe this is the cause that it just works ?
There are also reports that such disks albeit slower are running much cooler.
Power consumption test:
https://www.legitreviews.com/mydigitalss...w_206201/7
(12-26-2019, 09:41 AM)as400 Wrote: It looks to me like there are problems with NVMe disks that are heavily cached with DRAM memory which uses a lot of power.
MyDigitalSSD SBXe doesn't have any form of DRAM cache onboard. Maybe this is the cause that it just works ?
There are also reports that such disks albeit slower are running much cooler.
Power consumption test:
https://www.legitreviews.com/mydigitalss...w_206201/7 ssp
Yes, and the new SBX eco's are supposed to improve on power consumtion over the earlier disks , I believe. I have run iozone tests and not seen temps over 37 degrees C. The warmest I have seen the disk as measured by smartctl -a is 40 deg. at the end of a kernel compilation with -j6 and all cores maxed out.
I had been looking for relatively inexpensive storage that would iit inside the machine and allow for decent battery life. So far this is working.
(12-25-2019, 08:04 PM)hmuller Wrote: That's great to 'hear'! @zaius will be happy to add that to his SSD data. Once they send out the corrected adapters I look forward to installing it.
OK
I'll go look it up and add it to the thread.
It looks like the 240GB is only $33 on Amazon. Although the description says it's 2280, the comments say it's 42mm. How long is it?
https://www.amazon.com/MyDigitalSSD-480G...B07Q758SVN
(12-26-2019, 09:41 AM)as400 Wrote: It looks to me like there are problems with NVMe disks that are heavily cached with DRAM memory which uses a lot of power.
MyDigitalSSD SBXe doesn't have any form of DRAM cache onboard. Maybe this is the cause that it just works ?
There are also reports that such disks albeit slower are running much cooler.
Power consumption test:
https://www.legitreviews.com/mydigitalss...w_206201/7
Yes, less power consumed, less heat produced.
(12-26-2019, 01:34 PM)zaius Wrote: (12-25-2019, 08:04 PM)hmuller Wrote: That's great to 'hear'! @zaius will be happy to add that to his SSD data. Once they send out the corrected adapters I look forward to installing it.
OK
I'll go look it up and add it to the thread.
It looks like the 240GB is only $33 on Amazon. Although the description says it's 2280, the comments say it's 42mm. How long is it?
https://www.amazon.com/MyDigitalSSD-480G...B07Q758SVN I ordered the 480 last night, I can let you know if I get the 2280 as shown on the page, or the 2242 the title and comments mention. Should have it Monday or Tuesday.
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