Tetent UMPC [gd0149]

Can I now make something better than a 2-in-1 laptop? Something that I can use outdoors?

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This is a theoretical version of Tetent that runs Windows.

(It used to be called Leti where the L stands for Long.)


Prior Reading


The title tag system is explained here, and the table is updated when a change occurs. Notable logs have bold L# text.

[R] Initial Project Research
[R] 5G Celluar Connectivity
[R] DIY Mini-LED 1440p LCD
- Using an LED matrix as the backlight
[R] Monitor Splitting Strategy
[T] Inbuilt A4 Document Scanner
[T] Inbuilt TWS Earbuds
[X] Screens need to be on the other side
[T] T80-Pro Mini PC as Potential Mainboard?
[T] Minisforum EM680 / EM780 as Potential Mainboard?
[T] A3 Contact Image Sensor
[T] T9 Plus as Potential Mainboard?
[T] Top and bottom 6.3" 1440p
[A] Details before 13 Jan 2024


This project is to research if I can get most of the benefits of the #Teti [gd0022] and #Tetent [gd0090] system whilst having something much more portable than a desktop PC with a handle.

  • [A] Details before 13 Jan 2024

    kelvinA01/13/2024 at 13:18 0 comments

    This is a Ultra Mobile PC based on #Tetent [gd0090] that I plan to use to allow me to actually spend my time outside whilst doing computing tasks. This project received an internal  "gdXXXX" code on July 10th 2023.

    Notable Tetent projects, sorted by project log count:

  • [T] Top and bottom 6.3" 1440p

    kelvinA07/11/2023 at 22:44 0 comments

    The single required usecase of Leti is that I can compute outside. This would've been more convenient if 2560 x 2560px, 70-90PPD AR headsets existed, but they don't and #T^2 TyMist [gd0138] didn't work out since I don't have the optical manufacturing capability, nor the FPGA skill to take a DisplayPort 1.4 signal and mirror it so that it was the correct orientation when reflected on a curved combiner.

    That means I have to battle the sun, which seems to be a simple case of emitting about 1000 nits:

    Precisely 0 off-the-shelf OLEDs or LCDs I can use can reach this, though that 6.3" local dimming idea I had could be as bright as 1500 nits.

    Ergonomically, there are 2 issues. The first is that it feels like I'd want to keep the entire length of Leti at around 300mm / 12", going off of holding a 290mm box in a similar way. The second is that having neither of the screens centered just feels disorienting to me. 

    The solution to both of these problems is to have a single 6.3" screen, just that one is on the top and another on the bottom:

    Imagine Tetent is longer to fit the T9Plus mainboard in the middle.

    The top screen would likely be the main one, and the bottom screen for additional workspace.

    Another benefit is that I would be able to still use the UMPC like #Tetent [gd0090] when the screens are folded down, as the top screen shouldn't cover the Tetrinsics (or just barely).

    I'll have to worry about brightness uniformity and power consumption though.

  • [E1][T] T9 Plus as Potential Mainboard?

    kelvinA06/19/2023 at 14:53 0 comments

    Ahhh the day after the week-long AliExpress sale. I guess the T8-Pro N100 is back to its higher price now... wait, what's this?

    My mind's background music:

    So a freshly updated one has just come out and it's £4 cheaper than the T8-PRO N100 on sale but has RGB (for speed obviously). Still, unfortunately, comes with WIFI 5 / BT 4.2 when an AX210 would probably only increase their BOM by £4. I'd just get an AX210 anyway since the antennae inside the T8-Pro (which is probably unchanged in the T9 Plus) are small and stuck to the case itself. 

    It's nice that there's an option without SATA for £111, but with the UK / EU £135 thing, it's £20 more to get a 1TB, 3GB/s Nvme instead. If not for that, it would've been the cheaper strategy. The  

    It's also nice to know that the N100 boosts to 25W, though I expect most usage to be at 15W.

    The size of the T9 Plus is 85*85*43mm. I think the extra height is just because of the RGB. I'm considering aiming for Leti to be 44*88*352mm, using the 6.3" screens that have a built in backlight to reduce thickness and development time.

    [27 June] The 512GB and 1TB options are now NVMe drives:

    [1 July] The seller just told me that the 1TB NVMe is 1800MB/s.

  • [T] A3 Contact Image Sensor

    kelvinA06/18/2023 at 07:50 1 comment

    It's almost certain at this point that Leti will be over 300mm long, so only having a scanner that can do 210mm seems like a bit of a missed opportunity. Unlike A4, a handheld A3 document scanner basically doesn't exist. There are A3 all-in-one printers though, so I thought that I just had to surf though AliExpress and see if any particularly long looking CISs were used in A3 printers.

    Within 10 minutes, I found this sensor that is used in: WF-7610 WF-7110 WF-7100 WF-7111 WF-7621 WF-7620. There's also another sensor that also includes WF-7710 WF-7720 L1455 and another for the WF-7715. I think they're all compatible with each other, but with subtle differences (and more expensive). This one is the most noticably different:

    compared to

    Still though, I wonder about the possible conflicts with using the T8-PRO N100 motherboard.

  • [T] Minisforum EM680 / EM780 as Potential Mainboard?

    kelvinA06/15/2023 at 16:57 0 comments

    On researching for the previous log, there's also another Mini PC that comes in at a similar 80*80*43mm package:

    Like with the Framework motherboard, I'd have to use one of the USB4 ports as an internal way to both power the device and send data to the 2 side screens (with the centered screen being connected straight to the HDMI-out port). 

    The recently announced EM680 is a 6800U-powered minipc expected to be $609 (£477) for the 32GB + 1TB model, which is the savings of around £200 compared to the Framework mainboard + 3rd party RAM, storage and Type-C power adapter. 

    Only 1 USB4 port would be exposed, but looking at all the x86 handhelds that have come out recently, that should still be fine. I still wish USB kept with the 3.0 / 3.1 / 3.2 naming scheme, but alas, these have 3.2 Gen 2 (10gbps) ports. Like with the T80 Pro, 2 of these ports will be exposed and one of them will be used for internals such as the dual 1G ethernet, 5G modem, Tetrinsincs and the scanner (if I can get it to fit).

    The EM780 is the 7840U powered equivalent that has been mentioned here but there isn't a product page like there is for the EM680.

    As I've already researched, the 7640U is about 11600K-or-better. It also seemed like the iGPU performance was halfway between the difference spanning the 6800U and 7840U. The 680M in the 6800U is 5X better than the iGPU in the N100:

    6800U or the N100?

    I'd imagine that the battery life for general computing would be more beneficial in this application. The performance was still i7 grade back in it's day, and stuff that would actually be taxing to the hardware of today likely would want something with a dedicated GPU anyway. 

    If anything, saving the ~£300 to put towards the Pocket AI A500 (~£337) or GPD G1 (~£550) would likely see more of an experience improvement. Oh, wait, no that won't work since the T8-Pro doesn't have Thunderbolt/USB4. Pain. That stings a bit. Still though, I was designing complex models such as the #SecSavr Skyrise [gd0092] just fine on integrated graphics on Deti. It was 1080p, but I doubt Fusion 360 wouldn't be able to handle itself on QHD. Oh, and the 780M beats the A500 in synthetics anyway:

    The price of the EM780 hasn't been revealed yet, though.

    In terms of IO, the T8-Pro makes things much easier on my part than the EM680. I'd expect the dimensions of Tetent to be 360mm*90mm for the T8 but it might be larger for the EM680 due to the internal USB4->HDMI gear.

  • [T] T80-Pro Mini PC as Potential Mainboard?

    kelvinA06/15/2023 at 15:00 0 comments

    I remembered a mini PC I saw a while ago, but didn't know what it was called. Thankfully, "triple HDMI mini PC" was able to find it:

    Now, this is great because it has all the IO I was really hoping for in a UMPC: dual ethernet, 10gbps USB and 3 HDMI ports for the 3 displays. It's also great because of the price. I'm not hopeful it's going to last, looking at price history, but sub £160 for this is a really attractive offer for the reasons I'll mention in this log. 

    It looks like, if you time it, you could get the above config for sub £160.

    As you can see, the internals of this are rather simple. The great part is that the entire thing is 87*87*40mm in volume (though, elsewhere it says 80*80*40). This should be able to fit in a build that looks only slightly taller and thicker than a standard Tetent.

    Now I want to bring your attention to the laptop I called Deti:

    I had this for 4 years, and honestly the only reason why I had to bounce and create #Teti [gd0022] was because it was falling apart. The 2-in-1 functionality basically broke after a Windows update 2 weeks after owning it, but that 360 hinge was still very useful... until it broke of the backplate that holds the screen up about 3 years down the line, and the £65 replacement only lasted another year. (and I broke the digitalizer in the process of installing it). The extra storage HDD failed at around 3 years in too, as did the stock charger. Basically, it was costing more and more to keep fixing it and I didn't want to spend more when I'd only be able to upgrade to 16GB of DDR4 down the line (12GB was installed).

    But wait. The T8 Pro also only comes with 16gb of RAM (albeit DDR5 faster). 

    Yes. That's not an issue... for £155. My issue is when laptop manufacturers are asking £900 and up for 16GB. In that price segment, I essentially make 32GB a mandatory requirement. 

    Have you noticed something I haven't mentioned though? Processing power. I was FINE with the i7-7500U performance, and honestly the 11600K I have now didn't bring that much day-to-day performance other than speeding up the Fusion360 renderer, which is a multithreaded task. And look at these benchmarks:

    CPU-wise, I'm getting comparable performance to a £900 (on clearance) laptop from 2017 for 40% of the TDP (6W vs 15W). 

    It's a bit interesting to know though that the N100 only supports single channel memory. It's still faster, though:

    N100 left, 7500U right. The 7500U also supports 32GB of memory, but every (touchscreen) laptop I could find could only be upgraded to max 16GB anyway.

    My concern is a bit more with the GPU, looking at this:

    The T8 Pro is advertised to be able to run 3 UHD displays, so 2 QHD + 1/2 FHD should be within it's ability. If it can run Fusion360 it's probably good enough for me. I looked to see if I could find more benchmarks, and I found this which shows that the 24EU's are about or slightly faster than UHD620, depending on the benchmark. Intel hasn't changed anything between Alder Lake and Jasper Lake EU's.

    Looking at this, it does seem that the chip can actually boost way over 6W though. Anyway, it totally looks like Intel made the i7 of 7-years-ago here, and it's about 2/7ths the price of the lowest cost Framework+32G+2TB strategy. 

    The T8-Pro looks great, though there isn't a 2TB option in the listing (even though it's supported). 1TB + OneDrive is probably fine. The BT is also only at 4.2, but that can be solved with a small internal USB dongle (or the Tetrinsics perhaps?) Ideally, the exposed ports for Leti would be everything minus 1 USB3 port (for internal connections to things such as the 5G modem and Tetrinsics), but that would require some HDMI switcher circuitry to direct the signal either to the inbuilt screens or external ones.

    For a minimum-viable-product, all I'd really need to do is solder 2 wires to bypass the barrel jack connector....

    Read more »

  • [X] Screens need to be on the other side

    kelvinA06/14/2023 at 12:36 0 comments

    [X] = Experiment

    So I'm reading between office chairs and beanbag chairs, thinking that I'd opt for the latter inside #TrueTent [gd0143] if this UMPC existed. I then got an idea to poisiton myself similar to how stock-image people were sitting in their beanbags and held my current keyboard as if it was Tetent. 

    The red rectangle is where my eyes would actually be. The angles either my hands, eyes or neck would need to do to see screens in their currently expected position would be unergonomic.

  • [T] Inbuilt TWS Earbuds

    kelvinA06/06/2023 at 02:04 0 comments

    For Leti, the idea is that everything I'd ever need to be productive is all in one package. Something I noticed that was missing was the ability to listen to sound when in a public space (and a microphone, to a lesser extent).

    Like a few smartwatches that are available right now, I'm thinking that built in TWS earbuds is the solution to this. However, since the TWS earbuds I'm seeing have a runtime of typically 4 hours, the strategy is to actually hold 4 earbuds in Leti, not an expected 2. This is so that I can quickly hot-swap between buds. 

    It's rare, but there are a few earbuds that have removable batteries. The reasons why I'm not opting for a similar strategy are

    • TWS earbuds are rather cheap.
    • Changing the batteries is likely a 2-handed event.
    • There's more steps involved in swapping the battery as opposed to placing one bud back and grabbing a freshly charged one.

  • [T] Inbuilt A4 Document Scanner

    kelvinA05/23/2023 at 22:01 0 comments

    Since I'm unbound by the generic requirements of "the masses" and have complete idea freedom until "the rubber hits the road", as they say, I was wondering about any additional features I could install into Leti. The requirement was that:

    1. it had to actually be useful, and
    2. it needed to fit inside the space available, as well as not being possible to do in a smaller form factor by using a phone.

    Those 2 points eliminated the first round of ideas, such as a high FPS camera, 360 degree camera or infared camera. The first point stopped me from considering a pico projector, which happens have existed in quite a handful of phones actually:

    I thought there was only 1 .

    Anyway, I then thought back to when someone made a reddit post in r/framework about "dumb" expansion bays, where I suggested an A4 doc scanner. This is the humble pocket scanner I owned way back in 2018 or 2017:

    It broke almost a year after I bought it, but it allowed me to get nice images of flat surfaces, however due to the design flaw that I'd like to address, it wasn't all that great at scanning books. Essentially, I need to get the scanner as close to the longest edge so that I can scan right up to the middle of the book. Still, it was quite fun to use, though a bit tedious since it was a seperate device that needed to be charged and you had to use a micro SD card to transfer the files to the PC and it cost something like £80 for the WiFi edition. With that WiFi edition, you'd actually need to connect to the network that the handheld scanner generated, so it's not like the workflow was all that much smaller.

    The idea would be to try and use the sensors I've found for the #SecSavr Suspense [gd0105], which is MUCH cheaper than the £50 I spent on that handheld scanner.

  • [E1][R] Monitor Splitting Strategy

    kelvinA05/23/2023 at 19:12 0 comments

    I think it's time I started researching how I'm going to get the side screens to act like 2 seperate screens. The main idea is to drive 2 screens from one TB-chip, just like below:

    In the image below, I show what any device will automatically display on the top, and how I actually want it to display on the bottom:

    I'm not yet sure if I want the side screens aligned to the top or to the bottom (as shown). I think the latter looks a bit like a 3D carousel.

    So I'm thinking that my options are:

    1. Give up on 90Hz OLED and go dual 60Hz Mini-LED 6.3's, even if Leti would probably be as long as a 16" laptop is wide (360mm). 
      1. Use the extra length to fit in a 148Wh battery (up from 111Wh). I'm not planning on flying, but apparently you can take up to 160Wh inside carry-on luggage. The 100Wh limit is for suitcases.
      2. The issue with this one is that 360mm might be hard to use one-handed and it may be uncomfortable to look at one screen or the other since I'd likely have to turn my head.
    2. Find software that can configure the screens.
      1. I found "DisplayFusion", but at this time it doesn't support fullscreen windows.
    3. Try and find a USB3.0 -> HDMI that supports 1200*1080px 90Hz.
      1. This would allow Leti to drive 3 external monitors instead of 2, since both Intel and AMD have a cap of 4 monitors on the iGPU.
    4. Run each monitor directly, and just turn off the side monitors if I want to use external monitors.
      1. I'd also need a second I2C bus since the TB-chip only supports 2 different addresses.
    5. Wait. What if I flip the script entirely and do 4, but the OLED is the center screen?

    Here me out here:

    Am I really going to pick this device up to skim though 25 research papers while I run computational fluid dynamics on a CAD model most of the time? 


    Why run dual QHD panels all the time when I probably could use less-than-HD real-estate more than 50% of the time? This would be similar to a laptop + 2 desktop monitors arrangement. This solution seems to get more of the benefits and less of the drawbacks:

    • Benefits
      • Higher utilisation of the TB-chips.
      • 2 QHD sunlight readable displays instead of one.
      • No bezel in the neutral neck angle (looking straight ahead) and I can hide the bezels of the QHD monitors behind the OLED panel.
      • Excuse for an even larger battery.
      • Main screen is the right orientation by default, and is 90Hz.
      • If I had 2 screens of slightly different PPI's, I'd prefer the center one to have the lower PPI since objects would be slightly larger than the ones on the secondary screen. 
    • Drawbacks
      • Still probably 360mm long. On the bright side, that gives Leti a body ratio of 3:1.
      • The center screen is a barely-passing 75PPD resolution, and I worry that websites will have display issues with 1080px horizontal.

    This not-a-notch design likely would be better as I'd more easily fit a webcam:

    [25 May: Edit 1] I'm also thinking of virtually splitting the 6.3" panels in half. The center screen has an aspect ratio of 0.9:1 and these virtual side monitors would have a very similar aspect ratio of 0.889:1. The fullscreen bug becomes a feature in this way too.

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