Log My handheld PC projects

[CC Ricers]

@msystems I might have to take you up on that PD charging module idea after all. I recently realized that the Framework has a 5V-20V internal buck-boost circuitry already built right in the board, in order to support a wide variety of chargers. It trickle charges at 5V but can support many chargers up to 20V. In theory I should be able to wire up any 3S, 4S or 5S battery configuration to power on the board, if it can be balanced and follow USB-PD spec.

Such a power source would just need a PD trigger module such as this one.

Given what I learned from my previous portable PC experiment, I could use 18650 lithium batteries for a different approach to powering, and also allow other case forms.

For example, with the original plan to use the laptop battery, it would have to be sandwiched in somehow, and had calculated that the whole case would need to be at least 28mm to 30mm thick all throughout. But with the 18650 battery setup, I can have the batteries just take up more space at the ends, while the middle section can become slimmer. This form will add "handles", much like the profile of the Steam Deck (but maybe not as pronounced) for a more ergonomic feel.

 

[msystems]

How would you go about monitoring your battery voltage? Just a simple sensor or LED for a manual readout, or try to integrate in your OS?

I did find a company that sells a voltage sensor with usb interface for windows/unix to diy your own power management interface. It might be too large for your project. It has a sensor and a hub. The smallest hub they make is USB dongle sized.

Precision Voltage Sensor - 1135_0B - Phidgets

This voltage sensor measures ±30V DC and connects to an Analog Input or VINT Hub port.

www.phidgets.com

I'm planning to use this system to get Windows to recognize my diy lithium battery pack as an internal battery for the DeskMini

 

[CC Ricers]

The sensor looks plenty small enough, but I'm not sure about the hub.

Someone on Reddit suggested that since the 10-pin battery interface is open sourced, I should fashion a 10-pin cable for the custom battery pack. However I'm still not sure how I'd set up the sensor wires in order to detect total capacity in voltage.

If it doesn't work out, I can just use one of the USB-C ports as planned and daisy chain the battery pack to a barrel connector, and connect one of those off-the-shelf LED battery indicators intended for 4S voltages.

 

[msystems]

So I have a funny idea for you. What if you find an existing usb-c power bank with indicator leds, intended for retail, re-house it if needed,, and design a slotted enclosure system for it, such that it can be inserted and then connects to the aligned usb-c receptacle on your device. Then you could have multiple batteries and charge them for use, and not worry about an internal charging system or monitoring.

Look at the shape of this one (its only 5v.. too weak, but the shape is nice)

 

[CC Ricers]

Seems like too much work for now, as I'm just going to go step by step and make the batteries work and charge before adding in the monitoring system. I can always use my multimeter to test if they're charging before I finally put everything together.

One of those steps is adding in USB power delivery.

I have a simple 12V 30W power bank that I use for testing and powering on some USB accessories. This does a great job powering on my LP Delta board which requires exactly 12V.

But it fails to charge or power the Framework board. I'm almost completely certain it's because the power bank lacks PD, since it's just outputting power through a barrel jack. So the next step here would be to get a power delivery board and hook it up to a cable I can split off and connect to the power source.

Aside from that, I've done some work on the new case design using this different battery setup. Still got more to do, but I really want to make the contours of the case look more like a handheld system.

The only thing I reused from the last concept with the stacked sheets is the motherboard tray. I still plan to use it, and it gives me a good reference to make sure all the needed parts would fit inside.

The following top X-ray view shows how the tray would fit, as well as showing the opening for one expansion card. In true Framework fashion, this card slot will allow for some customization. So you can have an extra USB port there, or even HDMI or DP port to use the handheld with a larger monitor. The other three USB-C ports will be used internally for the build.

By the way, this design uses a 7-inch screen with a 16:10 aspect ratio. Yes, I know I'm going back and forth with the screen sizes. But for this new design, it makes more sense.

 

[aromachi]

Concept model is looking really awesome. Love it.

 

[CC Ricers]

I set up a custom 4S battery pack with a balance board again, and connected it to a DC to USB-C extension. The batteries are tested and still have a very good charge. But as expected it did not power on the Framework. Will test again when the PD trigger board arrives.

Things I have to buy for the board expansions:

USB-C PD trigger board (Already bought)
Tiny USB 4-port hub
Pimoroni USB-C 3.0 or 2.0 breakout for USB hub
180 degree angle USB-C converter for PD board
USB-C flat extension cable, maybe needed for hub
USB type A expansion card

And of course, the screen itself, which will be ordered some time after testing more connections. One thing I want to make sure is that the USB hub it connects to can provide enough power to the screen. I had a problem with one cheap USB hub and another mini screen that it will intermittently turn on and off.

 

[Arboreal]

It's coming along nicely CC.
I just watched Linus' latest video out today about upgrading the Framework to 12th gen and using the old 11th gen board to make a slim desktop PC.
It immediately made me think of your project and all the good stuff you're doing

 

[CC Ricers]

It's coming along nicely CC.
I just watched Linus' latest video out today about upgrading the Framework to 12th gen and using the old 11th gen board to make a slim desktop PC.
It immediately made me think of your project and all the good stuff you're doing

And when it comes time to upgrade I can just swap in the board without changing anything else because they use the same mounting holes. Another great thing about these motherboards. Even the i5 version would be a big upgrade, doubling the number of cores and with triple the threds.

I see they're finally out now, and the 12th gen i5 is just $50 more than I paid for mine. Now I wish I had waited a bit longer

 

[CC Ricers]

While I'm still waiting on my PD trigger board, @AURMEND posted a link to GrabCAD where someone was able to hollow out shell pieces for the Steam Deck using the official CAD files. (I had once tried to do this myself but just couldn't get it right) So I got curious and took a look at those files.

After closer examination, this would actually be a nice design to use with the mainboard instead.

It's big enough to fit everything with no problems- including the WiFi card sticking out to one side- and still should have some room to tuck a battery in. And the screen size is the same (albeit mine will have a higher resolution ). AURMEND posted the link in the mods subforum so maybe this would also count as a Steam Deck mod, though really the case will be 3D printed after it's customized to work with the board.

 

[AURMEND]

what will this super mini mini running with? I reccommend a RPI CM4 if trying for something simple.

 

[AURMEND]

While I'm still waiting on my PD trigger board, @AURMEND posted a link to GrabCAD where someone was able to hollow out shell pieces for the Steam Deck using the official CAD files. (I had once tried to do this myself but just couldn't get it right) So I got curious and took a look at those files.

After closer examination, this would actually be a nice design to use with the mainboard instead.

It's big enough to fit everything with no problems- including the WiFi card sticking out to one side- and still should have some room to tuck a battery in. And the screen size is the same (albeit mine will have a higher resolution ). AURMEND posted the link in the mods subforum so maybe this would also count as a Steam Deck mod, though really the case will be 3D printed after it's customized to work with the board.

using those files you need tto add more screw holes since the steam deck uses a lot of clips to hold it in together, especially at the edges

 

[CC Ricers]

what will this super mini mini running with? I reccommend a RPI CM4 if trying for something simple.

It will be using something a lot more ambitious- a Framework mainboard which is a full laptop board with a Intel Tiger Lake processor. The board is very flat and would fit well inside the case. There have been other projects using these boards in custom cases like this one that is also small, but Steam Deck has a smaller footprint than that case and mine won't include a built-in keyboard anyway.

using those files you need tto add more screw holes since the steam deck uses a lot of clips to hold it in together, especially at the edges

Yep, making more modifications to the case includes different screw holes. I already had to add some vents around to make them line up with this board's fan. The Steam Deck's case screws are self-tapping and dig into the plastic. Instead, I'll use some heat-set inserts or other metal insert method to make it easier to replace the screws without risking damage to the case.

The top and bottom halves are also split further into more pieces to make it more 3D printer friendly and locking tabs will have to be added to join them.

 

[msystems]

You might try using round aluminum quadrocopter standoffs (either threaded on the whole length or with a male thread on one). All the middle layers are compressed together and kept in alignment by the standoffs. The outer layers have m3 thru holes and the screws come through and grip the round standoff. It makes assembly a breeze as you can mount the standoffs then drop in each layer.

 

[Valantar]

You might try using round aluminum quadrocopter standoffs (either threaded on the whole length or with a male thread on one). All the middle layers are compressed together and kept in alignment by the standoffs. The outer layers have m3 thru holes and the screws come through and grip the round standoff. It makes assembly a breeze as you can mount the standoffs then drop in each layer.

Are the standoffs actually necessary when you're 3D printing though? Printing sockets for heat set threaded inserts puts them right where they need to be, while saving the trouble of finding or cutting standoffs to just the right length, while ensuring the same ease of assembly as those standoffs.

 

[CC Ricers]

If 3D printing and using standoffs I could also just adjust the base at the interior in order to get the standoffs to exactly fit. Still not exactly clear on whether I go with removable standoffs or heat-set ones.

Also they could as well be screwed in on the sides with tabs holding short standoffs so the insertion force would be sideways and not top-bottom. I had made a 3D printed ITX case that uses hex standoffs of various lengths, and fit inside hex-shaped holes while another screw holds them from the opposite end.

Framework also provides official technical drawings of their motherboards, and it fits well inside the Steam Deck, which I had already started modifying the case. I've added some vents to go around the Framework's CPU cooler (Steam Deck's are on the right). There's still some room to route cables and other extensions. The controls sit about a centimeter above, so they are not in the way.

This is one possible battery configuration I could go with. The case does need to be made thicker in the bottom middle to fit the two middle batteries, though.

@AURMEND It might interest you to know someone already made a Steam Deck replica with a RockPi X in it. His is used more for game streaming.


It also demonstrates the use of battery cells in the handles. Although that replica uses 21700 size cells, mine are 18650 (so I use 4 for more capacity).

Either way could be good, though, especially if those 21700 cells are 5000 mAh each, which makes for a total of 38.5 watt hours. The official Steam Deck battery uses 5313 mAh which gives almost exactly 40 Wh, so it's close.

 

[Valantar]

If 3D printing and using standoffs I could also just adjust the base at the interior in order to get the standoffs to exactly fit. Still not exactly clear on whether I go with removable standoffs or heat-set ones.

Also they could as well be screwed in on the sides with tabs holding short standoffs so the insertion force would be sideways and not top-bottom. I had made a 3D printed ITX case that uses hex standoffs of various lengths, and fit inside hex-shaped holes while another screw holds them from the opposite end.

Framework also provides official technical drawings of their motherboards, and it fits well inside the Steam Deck, which I had already started modifying the case. I've added some vents to go around the Framework's CPU cooler (Steam Deck's are on the right). There's still some room to route cables and other extensions. The controls sit about a centimeter above, so they are not in the way.

This is one possible battery configuration I could go with. The case does need to be made thicker in the bottom middle to fit the two middle batteries, though.

@AURMEND It might interest you to know someone already made a Steam Deck replica with a RockPi X in it. His is used more for game streaming.

It also demonstrates the use of battery cells in the handles. Although that replica uses 21700 size cells, mine are 18650 (so I use 4 for more capacity).

Either way could be good, though, especially if those 21700 cells are 5000 mAh each, which makes for a total of 38.5 watt hours. The official Steam Deck battery uses 5313 mAh which gives almost exactly 40 Wh, so it's close.

Looking good so far! Btw, have you looked into running your screen directly off the Framework's eEP port? From what I understand eDP is essentially universally compatible, meaning it should be plug-and-play as long as the backlight voltage is correct and you can wire up the cabling correctly. That would likely take some very fine soldering or ordering a custom eDP cable, but it should be doable.

 

[CC Ricers]

Looking good so far! Btw, have you looked into running your screen directly off the Framework's eEP port? From what I understand eDP is essentially universally compatible, meaning it should be plug-and-play as long as the backlight voltage is correct and you can wire up the cabling correctly. That would likely take some very fine soldering or ordering a custom eDP cable, but it should be doable.

I'm still trying to figure out how to make that possible, especially for just about any HDMI compatible screen since I already ordered mine from AliExpress, and most panels there accept HDMI much more than DP. Things would be more straightforward for a DP monitor.

Others on the Framework community forums are more interested in running a secondary laptop monitor off HDMI. In other words, they want to use a HDMI expansion and convert that to eDP for output. Here is one such module that can do that. But I have to look for something that does the reverse, take eDP input and output to DP, which then I have to convert to HDMI. And also be compatible with the pinout.

 

[Valantar]

I'm still trying to figure out how to make that possible, especially for just about any HDMI compatible screen since I already ordered mine from AliExpress, and most panels there accept HDMI much more than DP. Things would be more straightforward for a DP monitor.

Others on the Framework community forums are more interested in running a secondary laptop monitor off HDMI. In other words, they want to use a HDMI expansion and convert that to eDP for output. Here is one such module that can do that. But I have to look for something that does the reverse, take eDP input and output to DP, which then I have to convert to HDMI. And also be compatible with the pinout.

Are you sure those HDMI monitors don't use eDP internally? For the panel itself (not the "display", which includes the controller board), it's either eDP or LVDS, and my impression is that LVDS is so old that it's essentially not used any longer. The HDMI tends to be handled by a controller board that converts that HDMI signal to eDP, while (at least on paper) you should be able to connect any eDP source to any eDP target with just a simple cable, no controller board needed (though you'll lose any OSD functionality through this, of course - just like a laptop).

Edit: ah, I forgot, if the panels are made for mobile use they might also be MIPI DSI. If the monitor you ordered is the 8.9" one you mentioned above, that sadly looks like it's DSI and not eDP And all I can find when searching for eDP/DP to MIPI DIS is controller ICs, no actual converter boards. That sucks.

(Oh, and that board you linked is USB-C, no? So it's likely DP alt mode-to-eDP?)

 

[AURMEND]

It will be using something a lot more ambitious- a Framework mainboard which is a full laptop board with a Intel Tiger Lake processor. The board is very flat and would fit well inside the case. There have been other projects using these boards in custom cases like this one that is also small, but Steam Deck has a smaller footprint than that case and mine won't include a built-in keyboard anyway.

Yep, making more modifications to the case includes different screw holes. I already had to add some vents around to make them line up with this board's fan. The Steam Deck's case screws are self-tapping and dig into the plastic. Instead, I'll use some heat-set inserts or other metal insert method to make it easier to replace the screws without risking damage to the case.

The top and bottom halves are also split further into more pieces to make it more 3D printer friendly and locking tabs will have to be added to join them.

Useng a framework board would be the BEST!