I just got a used devterm and it's not as bad as expected

DevTerm
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So I ordered a used devterm with a CM4 with 4GB RAM on eBay a little over a week ago. I liked the old HP handhelds and it reminded me of them. As I dug into the forums I was beginning to think I’d made a bad choice with all the talk of troubles with wifi, broken screens, and generally horrible experiences messing around with config.txt, lightdm, xrandr to get a usable image.

I’m not sure which revision of devterm I have. It has a CM4 in some sort of adapter on the board.

On my first try, I downloaded bookworm and dd’ed it to a 32gb card on my linux PC. Got an upside down image and could not for the life of me figure out how to launch an xterm and use xrandr to flip it. (The mate menu was off screen.) Read various outdated forums posts but gave up as I didn’t even know whether I was running Xorg or Wayland (then I’d need wlrandr?). Gave up, downloaded (debian-based) “Parrot OS” and dd’ed it to the card.

This time the screen came up perfectly and I went to configure wifi. And it could hardly detect my network unless I was standing right by the router. The forums revealed that CM4 has an onboard antenna connector and that there was controversy over whether it was better to use that one or the one on the devterm motherboard. I tried both settings in config.txt and it didn’t matter: wifi signal was very weak unless I stood by the router. Time to look inside the case.

After I took it apart, I saw that the wifi wire was plugged into the motherboard. I unplugged it and connected to the CM4. After that wifi problems were over: I downloaded Mathematica in less than half an hour. (I commented out the line in config.txt about the antenna, so I guess the default is to use the one on the CM4.)

By this time, I had noticed that the trackball was complete garbage. (Actually I’d just used a mouse up to this point! Why couldn’t there have been one of those Thinkpad eraser-looking things?) So I found in the forums that you can install some kind of xorg input method that allowed the “joystick” (looks like a D-pad to me) to control the mouse cursor. Tolerable, but the pointer acceleration is crazy huge. I’m not too put out as I mostly want to do almost everything with the keyboard (gonna install i3 or xmonad.)

Can this thing sleep, as in suspend to RAM? How do I do it from the command prompt?

One thing I really don’t understand about most of these pi-gadgets is why they all use crappy SD cards…I mean people go to all this trouble to make nice hardware and then you’re supposed to store data on an SD card? Would it have been so terribly expensive to have msata, pcie, nvme, whatever the current non-standard is in SSD drives?

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you got bad one, replacements are available on ali, you can find required sku somewhere on the forum

nope, raspberri can’t do such magic.

raspberry cm5 finally supports external storage, but clockworks’ devices don’t fully support cm5 :slight_smile:

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The default is to use the pcb antenna on the cm4, not the external antenna on the cm4
The antenna on the main board is connected to a second wifi module but that is not connected to the cm4 so you can’t use that one

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It also came with this weird 3d-printed frame around it. What is this thing? It just seems to add more weight to an already big device and doesn’t provide much protection….

thingy
thingy1200×1600 348 KB

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Well, I put that frame back on and find it is somewhat easier to hold the devterm. A few days into devterm ownership, I find that i3wm strips away too much and is a bit of a hair shirt to use as a dialy driver. (Maybe if I found the right status bar app….) MATE isn’t too terribly bloaty, although I don’t understand why DEs all feel the need to reinvent xterm as mate-term, xfce-term, foot, konsole, etc. (I just use xterm and tmux everywhere.)

So what fun things do people do with devterm? I found thislightweight terminal epub reader and it works nicely. I was looking because the included atril seg faults.

I see people talking about SDR a lot, but I kind of gave up on it 13 years ago: all I could tune was religious wackos, terse aviation jibber jabber, and all sorts of funny noises I could not identify. Is there anything interesting to listen to, preferably not requiring a HAM upconverter and/or an antenna as big as a whale?

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Interesting, that surround frame looks like it was intended for wall-mounting or such (thus the hood to block glare from above). Is there anything on the back of it to suggest it’s a mounting bracket? Can you upload a picture of the back of it?

If it covers the back, be aware that might potentially cause a thermal issue with the CM4, depending on a) whether it has the graphite heat sink installed, and b) how it was installed.

Also, thanks for the tip for epy-reader, I’ve been looking for something just like that!

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While I’ll admit there are definitely some design annoyances with the DevTerm (I too would have MUCH preferred a ThinkPoint device, and find the Blackberry-style trackball an annoying “RSI-enhancer”), but aside from that, limited GPIOs, and making the case a bit overly-finicky to reassemble due to the two little “port panel inserts” on the sides, and the power button in front,

Still, I’ve found mine quite useful as a tiny, easy to carry “serial terminal / wireshark-station”. I only wish they’d not used up basically ALL of the GPIOs on the internal interfaces, or given us an easy way to disconnect those devices so the GPIOs could then easily be accessed via the expansion port (see below). I’ve got enough to pull through a couple Dupont M-/F-ended to attach to external UART lines in worst case, though, and that covers a LOT of my needs.

Sure, m.2 NVME would have been a better choice than SD/microSDXC, but I can also understand how they might have felt power-/thermal-constrained adding decent-speed m.2 NVME support. I’m guessing there aren’t enough / fast-enough GPIOs unused to add one in exp. port area, either, otherwise we would have seen someone offer the plans & PCB for that by now.

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clockwork developed it for CM3 (and alternatives), and raspberry added NVME just past at 5th revision (past year).

there is a project with alternative adapter board for uconsole with NVME support, there is a chance this new adapter will work with devterm too.

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Do you have a pointer to that project by any chance?

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it wasn’t released yet and wasn’t tested on devterm, but it has similar motherboard to uconsole (lower revision or so)

doesn’t seem like clockwork cares to update motherboard by themselves :frowning: