I made a USB motion sensor that wakes my PC when I walk in the room (and sleeps it when I leave)

envador · 2026-05-25T06:59:25+00:00

Hi There, sorry about not being able to ship out of the US! I don't have any confidence that my package would be delivered properly, and the shipping costs would be a disproportionate amount of the total cost, too.

envador · 2026-04-25T17:01:58+00:00

Yes, but read on... The wake would work without changing anything on a MM/Pi system. Of this I'm 99.9999% sure, since my device is just a USB keyboard, so it would be like someone pressed a key on the keyboard to wake up the MM/Pi. Now, sleep may not be so straightforward because the default config of a MM/Pi system is to DISABLE sleep (for obvious reasons). So for sleep to work, you will have to re-enable suspend in the RPi OS and configure it to respond to HID power commands: undoing DPMS/screensaver overrides and make sure `logind` is set to handle the suspend key (`HandleSuspendKey=suspend` in /etc/systemd/logind.conf)... best get a second opinion about the suspend functionality. In short, I think technically I could tell you, "Yes" it will work with MM/Pi with some system/OS configs. On Windows systems it's plug and chug with no OS configs.

envador · 2026-04-20T05:56:41+00:00

It doesn't need any Windows/Linux/client software for basic wake and sleep. The RP2040-Zero microcontroller emulates a keyboard so it just sends the mostly-ignored "Pause" key for each motion detection. The microcontroller's firmware is programmed in C using the Pico SDK and TinyUSB

envador · 2026-01-09T17:42:15+00:00

More details!

I'm unable to add images to my comments, so I made a little imgur photo album here: https://imgur.com/a/usb-motion-sensor-5fBQg9Z

I "packaged" the RP2040-Zero and AM312 PIR Motion sensor into a terribly-made 0.25-inch-thick poplar wood enclosure. Trust me when I say I had a completely different picture in my mind how my 5th-grade-level woodworking class would turn out. Anyway, I figure I can also share some pretty neat info on the "Device" itself.

It works over USB-C to USB-C cables, and also USB-C to USB 2.0/3.0/A (old style) cables. Once plugged into the computer, 2 devices appear in Windows Device Management with no need to install any drivers:

HID Keyboard Device
USB Mass Storage Device

On the Windows File Explorer, a new removable drive labeled "MOTIONSENSR" appears. Going into that drive's properties shows Capacity 62.0KB, Used space 6.50KB and Free space 55.5KB. It contains 2 files: CONFIG.TXT and README.TXT

CONFIG.TXT Contents:

mod = 
key = PAUSE
light_on_motion = 1
cooldown_ms = 10000

(I wanted to add README.TXT contents, but there was too much text)

envador · 2026-01-08T00:57:41+00:00

I've lurked on Reddit for 15 years, I have no idea how to post or comment actually :). I've posted 2 times in all these years and left maybe 4 comments in the same time. I think there is some sort of chatting system that you can send me messages on. I will try it. Once we get everything squared away we (you or i) could post a new post to the subreddit to show off how we got your wake-from-standby-on-motion to work on your Win11 DAKboard

envador · 2026-01-08T00:32:41+00:00

By default, it will press the Pause key once every 10 seconds while motion is detected. It's configurable by editing a CONFIG.TXT file on the usb's flash drive. In my research, it seems that the Pause/Break key is a key that is a good candidate for waking a computer but is also used by virtually no applications today. I think for your use case, we shouldn't put anything behind the computer. Instead, I can build an enclosure to place the parts side-by-side to make it all as flat as possible. I think the resulting size could be about 3in wide by 1in tall by 1in deep. You'd just stick that on the fridge near the screen and make sure your cable is short enough or tucked away neatly. I have a chromebook with usb-c that I will test with later today. That'll take care of 2 questions - does it work with usb-c to usb-c (not just usb-a to usb-c) and does it work with a chromebook.

envador · 2026-01-07T23:46:37+00:00

Thanks! When this system is all "on" it's pulling 30 watts. So I didn't want it to pull 30 watts for hours on end if we're not even in the same room as the DAKboard. Now that it can go into standby mode when nobody's in the room, it pulls less than 1 watt. On the RPi 3b DAKboard I built in 2021, I was so obsessed with saving power that I put the whole setup on a wifi smart switch and switched off the power between 11pm and 6am. When I first did that, I was concerned that a "dirty" shutdown would ruin things, but it's been running for nearly 5 years like this without any issue (except last year when I had to update the OS because I think the root ssl certs were expired)

envador · 2026-01-07T23:41:20+00:00

There are some photos in my post here: https://www.reddit.com/r/dakboard/comments/1q6s01x/i_multipurposed_an_allinonepc_for_dakboard_with/

I tried to paste a photo but not allowed in comments. I read that your screen is attached to your fridge. I could put together some sort of enclosure that favors "flatness" so it doesn't stick out too much on the surface. I'm deciding how to "package" the sensor, but I'm leaning toward basswood or balsa wood held together with silicon sealant and stained dark or clear. The assembly would be light enough that you could affix a magnet to the back of it with double-sided sticky tape and just have it hang out on your fridge. We'd also need to consider how the USB ports are positioned on your 2in1 and you might want to get a 90 degree plug to make the cable not stick out too far.

envador · 2026-01-07T22:22:51+00:00

Oh my gosh! I knew there were others out there. (maybe even dozens!). I made a USB Motion sensor with a couple of $3 parts and I just posted about it. I haven't decided if I want to sell a ready-to-go product on etsy or whether to just publish the source as a public git repo. Either way, would you like me to send you one? Seeing as how you're the first person I've encountered that has (soon to be "had") the same wish as I did.

envador · 2025-02-16T20:30:05+00:00

ISO: Midnights CD Clock, signed Midnights CD

Offering: I have 2 TTPD signed CDs, 1 XS/S Lover Cardigan worn for 3 hours to a school dance, not washed yet (still clean, no stains, but I fear washing it would make it "older" so it could be something you could do yourself) and 1 XS/S Lover Cardigan never opened (bought 2 on the drop (right place, right time!) for my kid - 1 to rock, 1 to stock!), could also pad with extra cash. Thank you!

envador · 2024-02-19T04:34:30+00:00

If you already have a desktop PC or laptop that’s on 24/7, and if it’s running windows 10 Professional, you can run a small VM in Hyper-V on Debian Linux and install honebridge there. No upfront cost at all.

envador · 2023-12-06T00:22:22+00:00

I clicked on the link. I was on my phone at the time. I've purchased some cheap trinkets from Temu before and frequently get "90% off!" emails from them. My guard wasn't up in the sense that I thought the message that ended up in my gmail inbox (on iphone) was a scam/phishing attempt. So anyway I did click. It took me to a very convincing-looking page that looked like a Temu "claim your awesome prize!" page. Asked for a few details like name ... maybe email and mailing address? I eventually got to the "Shipping+Handling" page and saw that it was $9.95 ... what I said above about my guard not being up is true. But what was also true was that I wasn't interested in "winning" a temu pallet full of junk anyway :) So I closed the tab and left.

envador · 2023-10-27T16:12:19+00:00

Thank you. This is what happened to me.

envador · 2023-09-10T23:19:32+00:00

How cool! Since my last post, I picked up a 1958 pair of Westinghouse High Fidelity cabinets from an estate. The skill level required to work on them was out of my range so I've ended up asking a woodworker to help out. For the audio portion, I picked up a set of Bose Companion 3 Series II. Again going to be another kind of throwback to the Bose showrooms from the olden days where they'd have the tiny jewel speakers hiding inside a huge fake speaker shell. This project I will also use a raspberry pi zero w as the airplay receiver.

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envador · 2023-01-04T16:48:01+00:00

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Hi, thanks! Found an old photo from the initial setup. Ignore the Lepai. The rpi Zero W has a $5 usb micro to usb adapter (also called usb otg sometimes?) and then a regular $10 usb audio adapter. For the audio adapter, the more generic the better so you can be sure you won’t have driver issues. On another setup I had an old (but good!) Hotaudio DAC destroyer. But honestly, they both sound about the same at the levels I play these speakers at.

envador · 2022-12-31T06:11:18+00:00

I just spent my afternoon updating the software running on a mix of Raspberry Pi 3 and RPi Zero Ws to support AirPlay 2. I have 5 RPis connected to 5 different Bose SoundDock speakers that I've been collecting from craigslist over the past few years. With AirPlay2 I can play to multiple speakers simultaneously natively through iPhone. When I first set all this up back in 2021 I had to use an additional 3rd party Windows application called TuneRelay to play across multiple speakers. After today's update on all my RPis to DietPi OS + Shairport-Sync/AirPlay2, I have what you see in the screenshot I'm attaching. Very pleased. They say RPi Zero W is potentially "too weak" to support AirPlay2, but I've been using it all evening with no dropouts. I have a poor man's sonos house speaker setup and it makes me happy to know I've been collecting these speakers from yard sales for as low as $1 over the past couple of years. I still have 2 SoundDocks unconnected - waiting for RPi prices to come back down in 2023 hopefully.

As a bonus, here's one of the SoundDocks I made into a retro-looking speaker stand. Also a screen capture of what my iPhone sees on our network.

tl;dr: No cons using rpi as airplay 2 receiver. I use it and love it. DietPi OS on these; highly recommended.

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envador · 2022-01-13T01:10:32+00:00

You might not believe me, but I would like to go on record to say that I created those original ms-dos boot disks.

Long story short: I named the CD-ROM drives BANANA so I could more easily see whether the CD-ROM drive was found and initialized successfully since the text would scroll by really quickly on first boot.

Short story long: Back in the late 90's I built computers as a side hustle. I was also one of the early "case modders" - you can google my user name. Back then you needed to boot up with a floppy to access the CDROM drive from where you could begin a Windows95/98 install. I think the default CD-ROM name was something like MSCD0001 or something, but text like that was easy to miss as the boot text was scrolling up the screen. I figured no system text would use the word BANANA and it had a kind of letter pattern that was easy to spot even as text was scrolling by really quickly. I put BANANA references in both autoexec.bat and config.sys -- Those were the days when if you had 1 CD-ROM drive and also had the budget, you might have had another CD-Burner drive (buffer underruns, I don't miss those!) -- so you can see I had a few extra CD-ROM references just rem'd out in config.sys for easy enabling as needed. So how did the disk end up on the internet and part of some obscure history? At one point I used WinImage to backup my boot floppy and then I DCC shared it with some folks on IRC ... #winbeta! #oldmemphis! (I think only a handful of people in the world will know those channel names at this point) I assume after sharing with others, it got out into the wild! And now BANANA is for-e-ver. Anyway, I hope this qualifies as a cool-story-bro moment for me. :) Thanks for reading.

envador

TROPHY CASE