Close
0%
0%

DLT one - A Damn Linux Tablet!

Modular Open Source Hardware Tablet that is easy to hack and can run a standard Desktop Linux Distribution (or Android)

Similar projects worth following
Proper Linux Tablets unfortunately just dont exist and certainly not ones that are also open hardware.
I want hardware that does not lock me into a specific OS or cripples other options by the lack of drivers. I'm also sick of the lack of modularity and repairability of modern hardware.
So I will create the following.

A basic system for a modern and highly performant portable device (e.g. Tablet) in the 7-10" form factor.

The electrical and mechanical design will allow for a multitude of form factors in the future, basing on a shared approach on how to interconnect hardware, so reuse between form factors will be possible.

These newly developed standards for modular portable devices will be open to everyone and the same goes for the design of the Tablet that is being developed here.

For more details please read my project logs and the detailed description below.
The development started with the HaD Prize 2019 and you will be able to follow every step of it.

Motivation:

For years I've been wanting to create a tablet like device based on a SoM (System on Module). Doing something from scratch, routing DDR3 RAM, eMMC etc. didn't seem realistic to me, this is not only really hard but also very expensive. So SoM it is, which comes with the additional benefit of user upgradability if the SoM manufacturer stays true to their pinout with successor products, which they usually do if the SoM is in any way meant for an industrial market.

Back then I started out with the Raspberry Pi compute module but the more I thought about my specs the clearer it was to me that it just wont cut it.
I wanted something that can run modern applications, something that is actually very usable and is not just a cool thing on paper.

The past years I've been looking around for affordable SoMs that offer enough performance to be viable, until now there were either cheap outdated SoMs or ones that mainly target the industrial market and are too expensive.
In recent months there is finally an interesting selection of SoMs out there.

Technexion/Wandboard released the Pico SoM product range and the Pico Pi as a dev board. They range from 72-150$ For 150$ you get a fairly decent ARM SoC with 4K video support, 4GB RAM, 16GB eMMC and 802.11 AC WIFI and Bluetooth 5.0.

Essentially the basic specs for a modern tablet.

The other SoM that just popped up recently is the Nvidia Jetson Nano. Very capable SoM with similar specs but lacking WIFI. Though the GPU is much more high-end than the iMX8M Quad.

Another very important part is the Display. Until now I never found a satisfying product that had a good picture quality and resolution. It just feels wrong to use a 800x480 display in 2019.

For some reasons there are really great IPS displays popping up all over the place from 1.8" to 13" there is something in every category and all of them can be considered to be "retina" displays. If I want to make a tablet I don't want it to feel like tech from 10 years ago.

So the goal is to make it good or go home :)

What this project will then essentially entail is to design a carrier board for one the two SoMs (though I want to see if I can keep it generic enough to allow for different SoMs in the future) and create a mechanical design that will fuse display and carrier in a visually pleasing way while maintaining the goal of hardware modularity end reusability.

What:
My MVP will have the following specs:

  • Fast enough SoC/SoM to run a modern web app without lag.
  • Enough RAM for more demanding applications >=2GB
  • 802.11AC Wifi and Bluetooh
  • USB for charging and data >=USB2.0
  • High-res display in the 7-10" range connected via MIPI DSI or eDP.
  • Modular peripherals, the carrier should be very small allowing different peripheral connectors to be attached through FFC cables. A choose your own peripheral kind of product.
  • A parametric case design that allows for different screen sizes and peripheral openings.
  • Battery and charging circuit. No idea how large but I aim for around 4h+ active usage for now.
  • Extensible storage via SDcards
  • Audio
  • HDMI

Cool things for the future:

  • USB-C PD
  • Desktop peripherals that you never see in mobile products like an Ethernet Jack.
  • mPCI-E connector ( I never touched PCI-e so lets see how that goes). This would technically also allow for M.2 and adding a proper SSD to your tablet.
  • This does not have be a tablet, if I can make it small enough a phone is also possible, at least a phablet.
  • USB 3.0+
  • LTE either through USB or PCI-E
  • Camera
  • Keyboard "dock" to turn it into a Laptop

Here is a block diagram of what I'm looking to develop, this might change slightly in the future as the design progresses.

Visualization Images Courtesy of:
Wise Technology
Nvidia

ICs and other hardware parts are generously sponsored by MESO Digital Interiors https://meso.design/en

  • Manufacturing and the target audience

    Prof. Fartsparkle07/08/2019 at 23:17 0 comments

    A topic I haven't talked about in too much detail yet.

    Its something I'm constantly thinking about whenever I change something in the design. The tricky part is that I want to reach two main target audiences which require somewhat conflicting mechanical design.

    The first one being the general open source crowd, no matter if they are interested in hardware or not, there is quite a lot of interest from people who are interested in Linux and open development. They mostly want to see a tablet that comes close to a polished commercial tablet, from the feedback I've got it seems they are fine with something thicker but it didn't seem there was a ton of interest in fiddling with hardware or getting something that works but looks ugly. Small to mid sized industrial companies are also pretty interested in something like this, they would require a more rugged case and are also fine with thickness but also require a finished and polished product that is well integrated.

    Catering to this crowd is actually not hard, you require a few injection moulded pieces of plastic (I try to keep it as simple as possible, so far I see about 2-3 large pieces of plastic) and make a design that is constrained and tries to squeeze the hardware into any space there is to yield a tablet that looks nice and tidy, just as a tablet would look like that you bought from the usual Manufacturers. Sure there will be a few iterations until it comes out perfect but injection moulding is a well understand process and can be done in any quantity now a days. There is polyurethane casting for prototyping and small runs of 10-100pcs.

    Next step would be injection moulding with an aluminium tool, they are a lot cheaper to manufacture than the high-end steel ones and yield y few hundred to maybe 1k pieces and if you are going really big you can scale up to steel tools and produce several 10k-100k per tool ( I pulled those numbers out of my nose but this is the range I remember).

    The issue is that I can't design the mechanical parts so that they are only feasibly manufacturable with injection moulding.

    This is because I have a second target audience that I personally find most exiting and is what drives me personally. It's the hardware hacker crowd, the educational crowd, the mid-size company that wants 10 super specialized tablets that integrates their own weird oddball hardware.
    Those people want to modify the hardware, they want to experiment, they want to make their own spin-off.

    For this audience I need to think about hack-ability. It doesn't mean they don't want a somewhat good looking tablet, but extendability is key here.

    This is one reason why I design the electronics in a very modular way, no peripheral is fixed, everything is changeable. Don't need HDMI output? Then don't get the HDMI PCB. Need it 2 years later? Just buy it for a small amount and add it to your tablet, no need to buy a whole new thing. This not only allows upgrading to some degree, it also allows for great repairability which is something pretty much everyone likes.

    Now there is a catch here, how do I add an HDMI port to a case that doesn't have an opening for it?
    This why I decided to design the case in the following way. There will be a display assembly that consists of LCD, Touchscreen (the two will not be bonded for repairability) and a plastic 'spacer' that creates a frame around the LCD. This assembly is then acting as a flat surface where the aluminium plate will be attached to.

    This plate will have a sort of pegboard pattern of 2.5mm threaded holes where the electronics can be attached to, this allows for free placement of all peripherals and the motherboard. This plate can be easily manufactured in lots of different processes, its thin enough to be done in a sheet metal process, using water-jets or lasers, or more expensively, on a milling machine.

    The tapping will be a bit more expensive than just having threads in a limited amount of places for a fixed set of peripherals but this...

    Read more »

  • LCD and Touchscreen combo

    Prof. Fartsparkle07/07/2019 at 20:46 0 comments

    I got a nice 8.9" eDP LCD and a fitting touchscreen with a glass cover in typical tablet style, they only got white in stock, I would prefer black for future tests but it works well for first tests. Touchscreen was working perfectly in Ubuntu out of the box.

  • Revision 2 ordered

    Prof. Fartsparkle07/07/2019 at 20:34 0 comments

    It's been quite a while since the last update. Some private events kept me busy for a few weeks and I had somewhat of a slump, the second prototype was all about defining sensible pinouts for all the FFC's, finding out what connectors to use, what pin counts, what problems could arise in different applications than mine with the pinout I'm choosing and lots of other little decisions.

    It's important work but can feel a bit like a drag because you essentially just redo what you already did in a different way.

    I've worked through the slump and churned out a new motherboard and over the weekend I made 7 little peripheral breakouts.

    This will be the first proper proof of concept. The part I'm most anxious about is the eDP to LCD part, I've never talked to eDP LCD directly before, so lots of stuff I could have missed.

    Now that I'm waiting probably about 2 weeks for all those boards to arrive I will focus on milling a prototype aluminium frame to attach these PCBs to. I also got a nice LCD and touchscreen from a vendor, more about that in the next post.

  • Found all the bugs, working on next design

    Prof. Fartsparkle06/12/2019 at 21:17 1 comment

    So turns out I simply forgot to connect the AUX_GND pin for the DisplayPort connector, a quick bodge wire and DisplayPort was working as well :)

    Ethernet is only 100Mbits because I mixed up the connector pinout. Molex had two versions for the part that I used and for some reason the bi-color MagJack has a different pinout for the diff. pairs rendering 2 pairs useless which makes me end up with just a 100Mbit connection.

    I have ordered the correct part for the pinout and will see if it works ok after reworking it.

    I'm currently in the process of designing the next prototype which will be the actual first prototype meant for the tablet instead of a SBC like before.
    It will be as compact as possible and breakout everything over FFC like I planed. This also means I have to spec the electrical standards for each peripheral. This will probably not be final but its important to keep future solutions in mind here already. After all its supposed to be a universal standard for portables, not just for my initial tablet here.

    I expect this to take another 2-3 weeks as I wont have too much time due to private life stuff.

    But I want to see it assembled in mid July and maybe do a second revision before the judging deadline in late August.

  • It's alive!

    Prof. Fartsparkle05/28/2019 at 22:25 2 comments

    So the PCB came yesterday and it looks super pretty! It's a 4 layer board with impedance control.
    Also thanks to JLCPCB for sponsoring the board.



    The best part is, after soldering it together, it was actually working! Well everything except for DisplayPort.

    A friend suggested that I used the pin layout for a DP Sink instead of a DP Source. Who knew that existed! So you have the layout reversed depending on whether you transmit or receive the signal.
    I tried reversing the connector but that unfortunately did not change anything. Will have to further investigate why.

  • Mechanical Design

    Prof. Fartsparkle05/25/2019 at 22:03 1 comment

    I haven't talked too much about the mechanical side yet, which I want to change now. I did some sketches in Fusion to illustrate what I want to do here.

    I want to make the mechanical design akin to how a PC case works. So it is a generic mounting point and shell for the hardware, you are able to change hardware without also buying a completely new case.

    This is a bit tricky when you have so little room like in a tablet but it is doable to a degree. I want you to at least be able to swap out peripheral connections or add/remove them. Maybe you want a 6.3mm Audio Jack because you are an audiophile or you want a GPIO header on the side for hacking on the go.

    I want to keep the amount of parts needed to a minimum. This keeps costs down especially when manufacturing the project on a larger scale. If only have to buy tooling to 1-2 plastic pieces that saves a ton of money for smaller production runs.

    The frame is made out of 3 major pieces at the moment and is hold together by 4 screws (that might change as it is likely that is not stiff enough on the long side of the tablet).
    Here an exploded view of the current design. Bare in mind that this is still largely conceptual and it misses some details like studs that will be needed for stability of the back f.e.

    The back is hollow and offers room in addition to space the aluminium mounting plate already creates.
    This gives me 7mm space for hardware at the moment. I might have to increase this to 9-10mm by increasing the tablet thickness but I would like to avoid it. At the moment the tablet would have a thickness of 14mm which is about 2012 era tablet thickness. Which is still absoultely ok for me. This makes the product more hacker friendly (and repairable!). If you are looking for a 7mm iPad you will probably just get an iPad...

    The idea with the mounting plate is that it defines a mounting standard similar to that of expansion slots in a PC case.
    It has M2.5 threaded holes which are spaced 5mm apart giving you a nice even grid of 5mm steps.
    There you can attach small PCBs for the peripherals that you wish to use (as well as the mainboard through another small mounting plate that takes heat away from the SoC to the large mounting plate).

    The mainboard will offer several FFC connectors that break out all relevant peripherals. So each peripheral will connect to the outgoing connector through a flat flex cable.
    This makes the mainboard itself very compact and you have the total freedom of where you want to have which functionality!

    The only thing you would have to re-do is the plastic backplate. There are two options here. Have this be constructed out of one large back part and several smaller spacer parts that you could put between peripheral PCBs to close up the sides.
    Or you have a single piece and you will have to print or mill yourself a new one.

    From a product perspective I might offer both options. The latter looks much nicer, the former is more hacker friendly but actually very cheap to produce. It would actually make it possible to laser cut the whole assembly.

    Here are some renderings. I'm still missing some dummy PCBs, I will add those in later to make it clear how the whole modular peripheral thing is supposed to work.



  • Switching to Jetson Nano

    Prof. Fartsparkle05/18/2019 at 16:27 1 comment

    After being rather frustrated with the state of documentation of the i.MX8M SoM and sparse design guide I'm now switching my efforts over the Jetson Nano from Nvidia.

    Among my main reasons why I will pause my efforts with the i.MX8M is the availability of a polished end-user Linux in the form of L4T (slightly modified Ubuntu), with the i.MX8M you get a lot of options but none are really meant as a finished piece of software for end use but as a base for your own build. This is great for someone designing a tightly integrated product but not so great if you want an easy to use general purpose system.

    Another reason is community support. There is simply no big community behind the i.MX8M yet. The Jetson ecosystem exists longer and existing work for it is largely compatible with the Nano. Also in the few weeks the Jetson Nano has been available there is big community gathering around it. Given that it also comes in the form factor of an affordable SBC would really help adoption of the plattform and in turn also help my Tablet get nicer software and guides from the community.

    Another reason is performance, especially for multimedia the Jetson Nano blows the i.MX8M out of the water and this is something I think most users would be interested in.

    I designed a first test board with a similar goal as I had with my previous breakout for the i.MX8M. Get to know the hardware and its issues. When I'm comfortable with it I will continue with the next iteration, a first prototype that would actually be usable in my tablet form factor.

    This first prototype will again just be a quick and dirty SBC. I also gave a bit more shit about HDMI and eDP, learning more about High Speed design and trying to do it "proper". I ended up rerouting the high speed stuff 4 or 5 times as I found more and more error the more I read into the topic :)

    The PCB should hopefully arrive end of next week. 4 Layer impedance controlled PCB this time.

  • Soldered up and finally booting

    Prof. Fartsparkle05/01/2019 at 22:38 0 comments

    So the first time I soldered the new boards the SoM was still not booting.

    Quite frustrating, then in a fluke accident I found out that the "ONOFF" pin is actually a pin from the PMIC and by connecting it to 5V and then letting it float again (e.g. "button press" with a piece of wire) makes it boot.

    I then solderd up a second board with all components and was able to SSH into the Linux via a USB to Ethernet adapter.

    So some stuff is working!
    On the HDMI side I unfortunately missed the pull up resistors on the EDID lines so that seems to not work atm.

    Also the CPU debug serial does not come up. Not sure what the issue there is, might be an issue with the level shifter or I got the wrong UART all together.

    Here are some photos of the process and the finished board:

  • Ordered second prototype

    Prof. Fartsparkle04/24/2019 at 11:59 0 comments

    I didn't get the milled PCB to work, I triple checked everything but couldn't find a root cause. Technexion is taking a look at my schematic so lets see what they have to say.

    In the meantime I just went ahead with a new design as I think it probaly is just a fluke issue that I just haven't noticed yet. I ordered a PCB this time to cast out any issues arising from a missing solder mask.

    My main goal is still to only get it to boot but I broke out a bunch more stuff in case I want to test more. I don't have high hopes for HDMI and DSI as I did not order a impedance controlled PCB this time and haven't taken much care to aproximate the impedance with this stackup but it will be interesting to see if it would still work, just to see how much you can abuse these high-speed busses before they completely crap out on you.

  • Unable to power up

    Prof. Fartsparkle04/19/2019 at 12:20 0 comments

    The past days I've been debugging my first try at a minimal carrier PCB. I milled a PCB that has power in, CPU debug serial, USB-A and HDMI.

    Though the only thing I wanted to get going so far is powering the SoM and getting a connection to the CPU debug serial.

    At the moment I'm struggeling to even get the SoMs PMIC to power up. I connected everything correctly according to the datasheet. All thats apparently needed is 4.2-5.2v on the VSYS pins and all GND pins connected. I continuintity up to the mating pin of the connector and they are all properly connected, so its quite puzzling why the PMIC wont even start up and produce the 3.3 and 1.8 voltages. I do get a minimal power draw of around 10mA when attaching 5V but other than that it just seems dead.
    SoM is still working fine in the dev kit carrier board so I haven't fried it either.

    If anyone is interested here is the datasheet for the SoM: https://s3.us-east-2.amazonaws.com/technexion/documentation/pico-imx8m-rev099.pdf

    A pic of the milled carrier board (yes the connectors are shit to solder, they have no alignment pins)


    Here the excerpt from the datasheet


View all 12 project logs

Enjoy this project?

Share

Discussions

bylaws wrote 6 days ago point

It could be an idea if you are using usb c to use dp over usb c. l4t has native support for the cypress CCGx Type-C controller but not sure if that can be easily brought

  Are you sure? yes | no

Prof. Fartsparkle wrote 6 days ago point

That sound interesting. Finding the right solution for PD is a challenge so far.

Do you have link for those kernel modules?

  Are you sure? yes | no

Asher Gomez wrote 07/10/2019 at 20:44 point

Another question, will this be sold on Tindie or any other platform?

  Are you sure? yes | no

Prof. Fartsparkle wrote 7 days ago point

No plans at this point, its very early in the development process. The first thing will probably be kits for self assembly but no ETA for that, I'm estimating that it will take a good year to get to that stage as I'm developing this in my spare time.

  Are you sure? yes | no

Asher Gomez wrote 07/10/2019 at 19:24 point

This is made for running full-fledged 32-bit Linux right?

  Are you sure? yes | no

colton.baldridge wrote 07/10/2019 at 21:07 point

The Jetson Nano has a 64bit Cortex-A57 processor, so it should run 64bit linux without issue.

  Are you sure? yes | no

bsdwatch wrote 06/20/2019 at 05:48 point

Nano docs have been released, I could collaborate with you, as I have full desktop Nano images built with Yocto, and well there is a Armbiian build and well Nvidias own Ubuntu.

  Are you sure? yes | no

jimmyplaysdrums wrote 06/18/2019 at 20:53 point

Can't wait to see how this evolves! 

  Are you sure? yes | no

Asher Gomez wrote 06/18/2019 at 18:29 point

Coming along real well! Can't wait to get my hands on one!

  Are you sure? yes | no

Peter S. wrote 06/15/2019 at 07:50 point

Cool, gimme !

  Are you sure? yes | no

Mhowser wrote 06/14/2019 at 23:44 point

I hope this doesn't die off like the Neo900 did...

  Are you sure? yes | no

devxxl wrote 06/13/2019 at 12:40 point

I've built one with Jetson TX2 a year ago, it works, IPS 1920x1080 screen, many usb ports, HDMI input for image recognition, classification and all sort of other stuff... tested up to 44C under direct sunlight at Abu Dhabi, CPU complex reaches up to 85C, has Li-Ion for stability. https://tarsens.files.wordpress.com/2018/12/img_0270ssss.jpg good luck with your experiment.

  Are you sure? yes | no

Kevin Kreiser wrote 06/13/2019 at 02:24 point

how were you thinking of handling the heatsink for the SOM or just cooling in general? it seems like the "OEM" heatsinks are all way too big to squeeze into your case (just eyeballing it). will active cooling be needed in such a tight environment? keep up the good work!

  Are you sure? yes | no

Prof. Fartsparkle wrote 06/20/2019 at 21:47 point

I hope to avoid it, I will post an update soon that goes into details regarding thermal design but essentially I want to reverse mount it to the large aluminium frame outlined in the mechanical design project log.

  Are you sure? yes | no

bylaws wrote 06/08/2019 at 12:58 point

You might want to consider using a bq24192 charging ic, it is well supported by the l4t kernel and provides an otg 5v vbus supply if needed. This can be paired with some USB PD chip if you want fast charging.

  Are you sure? yes | no

Prof. Fartsparkle wrote 06/20/2019 at 21:45 point

Thanks for the tip, I was looking through TI portfolio already but have a hard time deciding on a charger, they have a ton of options..

  Are you sure? yes | no

kwapiszon wrote 06/07/2019 at 11:12 point

Pine64 will be gread, but fpga will be greatest.

Small fpga are extremely nice glue for joining arm procesor and for example second arm procesor or x86 procesor or other fpga.

Power ware important. FPGA get small power and can emulate console/dos/zx spectrum etc.

  Are you sure? yes | no

Juan Rial wrote 06/07/2019 at 08:25 point

The i.MX 8M is what Librem is using for their Librem 5 Linux phone. I know you already went with another SoM, but perhaps their git repos are worth checking out, should the Jetson Nano not work out.

Anyway, once that phone is finally launched, a tablet becomes low hanging fruit for them. I guess we'll see a Librem tablet pretty soon as well. That means you can probably leverage their software efforts to improve the user experience of the DLT One. :)

  Are you sure? yes | no

Prof. Fartsparkle wrote 06/07/2019 at 10:51 point

Is their hardware open? I couldn't find anything last time I looked.
The i.MX8M is not dead for this projects, its just something I will look into at a different point when I got a working version going with the Jetson.

The Jetson Nano got a far better performance though, its one reason why I went with this first. The power users will be a lot happier with this than the i.MX8M. The i.MX8M is much more battery friendly though and a bit more power efficient, which is reeeally important for the small phone formfactor. I have a lot more thermal lee way with my 7-10" form factor.

  Are you sure? yes | no

Juan Rial wrote 06/07/2019 at 11:12 point

From their FAQ at https://puri.sm/faq/:

- Will this be an “open hardware” design?
=> Our intention is to have everything freed down to the schematic level, but have not cleared all design, patents, legal, and contractual details. We will continue to advance toward this goal as it aligns with our long-term beliefs.

So basically, that's the intention, but I don't think they have released anything yet. Then again, the thing isn't released yet either, they're still tweaking the hardware.

  Are you sure? yes | no

david.boosalis wrote 06/07/2019 at 07:25 point

Great project. I could see it filling a rather large niche for a   embedded  small touch screen  device. If it could support the Yocto build system I think it would be golden 

  Are you sure? yes | no

Prof. Fartsparkle wrote 06/07/2019 at 10:52 point

It is supported by third party efforts: https://github.com/madisongh/meta-tegra

  Are you sure? yes | no

BTPankow wrote 06/07/2019 at 02:19 point

Cool project! Where did you get the Jetson Nano hardware documentation? I’ve been looking all over for it, it seems like a neat piece of tech.

  Are you sure? yes | no

Prof. Fartsparkle wrote 06/07/2019 at 10:53 point

I had to sign an NDA. They will release that in a few weeks though, the current dev kit and module will change accoding to a forum post by Nvidia so its probably best that the current deprecated documentation isnt public.

  Are you sure? yes | no

JavaScriptDude wrote 06/07/2019 at 01:53 point

Is it possible to add a kill switch so if you want to go totally gene hackman (ala the conversation) by being able to disable the camera's, microphones and maybe another to kill switch for bluetooth, wifi (nfc).

  Are you sure? yes | no

Nicolò wrote 06/06/2019 at 19:31 point

Glad to see that I'm not the only one that create footprint upside-down Doh!

  Are you sure? yes | no

Prof. Fartsparkle wrote 06/07/2019 at 10:55 point

It turned out it wasn't the footprint, I just forgot to connect the AUX gnd in my schematic. DP is actually working now, will post an update soon :)

  Are you sure? yes | no

Renaud Lepage wrote 06/06/2019 at 18:49 point

A tablet with a Jetson Nano chip?

Gimme.

  Are you sure? yes | no

chris wrote 05/30/2019 at 08:44 point

This is way cool. I'm been so desirous for a full blown Linux Tablet, something in the hardware realm of the Microsoft Surface Pro. My needs are a bit more high end (lots of RAM ~ 32GB, and at least 1TB disk) as I'm running lots of VM's. Need something that can replace my laptop and iPad\Android Tablets...one device to do it all that runs Linux Proper (not WinBLOWS).


Best of luck with this...

  Are you sure? yes | no

Daniel Dunn wrote 04/12/2019 at 01:54 point

Awesome project! And it's a chance to fix the big mistake that 99% of portable devices seem to have. 4.2V is too high for batteries and it wears them out twice as fast as slightly less charge would!.   I think it would be cool to use 1 or 2 18650 batteries for something like this, because it's so easy to find them.

A Linux tablet would be great because Android is really restrictive about hardware access and it makes mesh networks way harder than they should be.

  Are you sure? yes | no

Prof. Fartsparkle wrote 04/12/2019 at 20:07 point

Haven't decided on a battery system yet but I will probably utilize a smarter IC for that which should offer settings for these kind of things which should be settable from the SoC.
I might even put it on its dedicated PCB so you can choose battery chemistry and charging circuitry yourself without spinning your own baseboard flavor.

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates