Raspberry pi Pico programming in C -- microwave oven monitor and reminder
ฝัง
- เผยแพร่เมื่อ 26 มิ.ย. 2023
- The challenges of making a project on the raspberry pi Pico in C, without using an IDE. Measuring microwave oven power consumption to figure out when we forgot food in the microwave and alert us to take it out.
Code on github:
github.com/Matthias-Wandel/mi...
Please see docs directory for how to set up development envoronment and how to build it.
Piezo transducers are actually louder if you glue their entire face to a thin, rigid sheet of material. They flex radially, so they really need a sounding board.
hard glue or flexible glue?
Both
@@peter2327 I usually use superglue.
the case of the microwave is probably a metal sheet.
@@jyvben1520 but the piezo transducer is not attached to it.
I like how you keep your mind sharp. Sometimes we NEED projects like this to keep the brain working. Thank you Mathias for posting!
Not sure if it is of help or not, but ESPHome for Home Assistant now supports RIp32040 boards for a number of things, including sensors. One of the features could be a reminder into Home Assistant to make sure that the microwave has been emptied before everyone leaves for their daily activities, or before heading out for a pot-luck, where the microwave was doing a final warm-up of the contribution. Keeping in mind that Home Assistant can send notifications to cell phones. Just a thought, and I imagine it would require quite a bit more work to add everything you can do with this, there. It's a though.
yes, but that means I have to fight with all this home assistant stuff. I'd much rather just lean about the pico than about home assistant
You're the king of the game. I would love more rp2040 projects here. Planning to build a rp2040 synthesizer myself one day.
You should have a look at some of the other stuff the Pico is capable of - it's really quite remarkable. Like the project that one of the RP2040's developers did where they used the PIOs to bitbang VGA resolution DVI/HDMI @ 60Hz! With an overvoltage, it can even do 720p, 30Hz. The second core is even completely free for whatever use you might have.
Thanks for using C and not giving in to the evils of the snake in the grass, Python.
I like using pyton on a regular raspberry pi, actually. For quick little proggys its great.
I've build a similar project for my coffee machine. A LED shows if the water tank is empty. At first I pointed the LED like you but later I moved the led behind the machine and point the LED to the back. The LED reflects very bright and big on the wood behind the coffee machine. You can try the same: Just mount your detection machine behind the microwave and point it to the back. If that works everything looks way cleaner and no one sees the wires of your device.
Good point. But I WANT to see my creation! The color of the LED is a godo debug indicator
It has to be asked: does it run DOOM? LOL!
I had an interviewee refer to Python as a "good pseudocode language". It really pissed a lot of people on the panel off, but you know what, it's true, and sometimes truth hurts! I recommended we hire them immediately.
As someone who got into trouble for referring to python as "alternative javascript", I also recommend your new hire. 😁
I like when you solve small, interesting, and useful problems. My Dad did that all the time. He was so smart. Just like you.
I bought a pico a while ago and have never used it. Who knew my favorite woodworking channel would provide the inspiration I needed to get it out and make something! :)
It's so cool to watch you do the electronics.
I've watched everything and it wasn't until you recently reviewed that movie that I learned you were with RIM and that they were from CA too and I am glad you never stop tinkering. I like the tech stuffs and the wood stuffs. But really the engineering...
Fantastic, I love this, fixing a problem that doesn't really exist but with such a considered and effective solution!
I am developer for 45 years and it's the first time I heard about your piezoelectric hack! I have to try that next time.
I got into tinkering with the Pico when it first came out with C, but it was horribly annoying having to unplug and hold the boot button. Because of that I've usually just either used Python or other micro controllers for my projects. This video informed me there are better ways, thank you! Back to Picos for demanding things once more!
Now with REPLs like thonny and Mu most of those reboot problems are gone... Like OP I use NPP for writing, paste into Thonny, and upload. No physical reset required for testing.
Mathias you are hardcore man. This kind of content is just amazing.
Fascinating project indeed, Matthias! Excellent work! 😃
Stay safe there with your family! 🖖😊
His experiments are not that dangerous.
I like that you can figure all this out but can’t remember if food is in the microwave 😂.
Super fun. I love tinkering with these little cheap computers (that, as you say, are more powerful than the first computers I learned to program in the 90s). I used a Pi with a handful of inexpensive temperature sensors to build up a picture of the temperatures in my garage, and then ran it thru the process of insulating the doors to see how much of an effect the insulation really had. All the electronics were a good deal cheaper than the insulation, which is good, because they worked well, while the insulation basically didn't. And I can keep using the Pi for other projects.
The Pico is great, I built a mini weather station with it and waveshare sensor module, a small LCD screen and it's wireless carrying the data via mqtt to a pi, very challenging in micro python but I have it running now faultless for months!
When I first got my Pico W there was little resources on how to set up a IDE for C, and after a few days trying, I baled and programmed in MicroPython with Thonny, but would prefer much more to use it with C. C is a man's programming language for sure.
I tried for hours to get the IDE working on Windows to no avail. If you weren't already, I highly recommend using WSL and connecting it to VSCode if you want to use C.
@@KNfLrPn Thanks. Next time I'll give that a go.
My grandma programmed in Cobol (well mostly assembly) for automation and her colleagues were mostly female so I'm sure she would say Cobol is a man's language for sure in the sense you're using that expression. X )
If Matthias ever played Minecraft you know he would go so hard with the redstone
I totally love your implementation. the use of the tiny board instead of a full size Rpi. no fancy display, etcetc. like things should be .
Next project: your wife wants an alarm for reminding you to put the toilet seat in the down position.
I loved every second of this video. Every thing is great, thanks!!
Im suitably impressed !...
You should add the tray from an optical drive to eject your food when it is done warming.
There are a few existing libraries for controlling ws281x style leds. Some even leverage the pi2040's PIO hardware. Not that theres anything wrong with bit banging and assembly. Thanks for sharing. I would be interested in hearing more about some of your projects from your time at RIM.
I wanted something I can understand
I enjoyed this very much. Thank you.
I definitely could use more annoying reminders around the house to actually get maintenance tasks done, cool idea
That is totally awesome! I was geeking out over the Linux part as I use Linux...😎
Yes, all projects that solve a thing, keeps you entertained and is flat out cool, are Great!
LLAP 🖖
your a very clever man i take my hat off to you matthias
literally a project I've thought about doing myself but with the oven oven and home assistant notifications
Thanks for the inspiration!
That pico may still be overqualified for the job. Awesome project!
back in the 80s, throwing a 32 bit 125 mhz dual core RISC chip at this problem would have been unbelievable. high end unix workstations or VAX minicomputers were much slower than that.
Hahaha You are uncredible. Keep it coming. Greetings from Iceland.
We have the totally opposite problem: our Philips-Whirlpool microwave beeps loudly ad nauseamum. So I opened it and stuck a blob of Blue Tac to the piezo -> blessed silence. Our kids have moved out years ago, different times need different solutions.
Mine is the same (Siemens), it's ridiculously loud and doesn't shut up until you give it some attention (open the door). I've been close to smashing it on numerous occasions. I like your solution.
My main problem is that I forget to turn on the microwave at all, and the rest of the meal is served before I remember the accompaniment waiting to be heated. Don't think there's a solution to that.
Could not agree more about the IDE's. Makefiles for me, and CLI tools.
I would personally prefer a quiet alert which happens more frequently. I cant stand obnoxious alerts - especially if im doing something higher priority atm. Cool project 🎉
Interesting project- Although isn't forgetting to eat microwaved food part of the solution, not the problem? Love your resistance to an overly complicated development environment. More small embedded projects please!
this is a cool project
Thoughtful solution
The end bit reminded me of my current soldering iron, it's like a RISC Pentium 1 without the add-on RAM 😅
if I had half as much knowledge as this guy I would be in trouble
piezo discs have specific resonance frequency at wchich they become very loud. The value is usually in technical data or you can find it by just sweeping for the right frequency
master class!
If you want the piezo really loud it needs to be attached to a tuned cavity centered on your preferred frequency, but that’s a whole new video. I just did a project with 162 of those LEDs, wired in a random order but accessed as a regular grid so I had to do a translator function in the esp32, will do Wi-Fi access for next year.
thanks for sharing. I'll turn on TH-cam alerts for you. done. easy
Mathias, I get my power cord ends at the scrap yard, thereby saving money as they are on my shop shelf when needed.
Damn that's cool!
I took a different tack with Pico programming, limiting myself to using Python as a way to immerse myself in the language and find it's limits(some), quirks(many), and perks(few).
Circuit Python has much better library support than it's parent Micro Python, but not as much feature support (notably missing threading/interrupts). Python's an interesting language from a goals point of view, that has been muddied by some bad legacy choices and some inconsistently overbearing dedication to early goals. I much prefer C variants but being able to more fully parse Python has opened up a wider community that's more discovery focused and newbie accessible, which has been nice.
this is super cool, could you do a video going more into depth on your software stack for c development with the pi pico, ive tried before with vscode but i could never get it working well with cmake and all that stuff
Ive seen some AIML facial recognition modules. Would be cool to take a snaphot of the microwave user, and then report the offender when food is left in the microwave.
File under: "Office Shaming". I like it
Hey Matthias, you might want to double check your Makefile. Every time you run make my toilet flushes.
I like the noncontact solution.
Kudos for your programing skills, mostly (even if small) for the assembly part! A wayyyyyyy more simple and just electronic approach would be use the transformer relay as a latching signal for other relay, and keep it latched until the circuit is broken when we pressed the door button (using the good old self latched relay circuit), of course i'm oversimplifying the explanation to keep the comment short, and also because there are various ways to do the circuit.
that would involve an awful,lot of hard ware to implement the. algirihm
@@matthiasrandomstuff2221 To reproduce the led effect and sound a bit more hardware would indeed be needed, however it all comes down to what we want, i was talking about a signal like a flashing led or so, a simple stuff. But hey i'm not criticize your approach by any means, we should do the way best meet our goals. :) And btw great video contents you have.
I bet you’d really like PIO. I don’t think it would be too much effort for you.
Didn't want to have to learn another thing. bit banging it did the job just fine.
Your showing promise as a EE. :) nice vid
I'm glad to hear at least someone likes the nonstop reminder beeps. To me, this is actually a very annoying feature that I wish I could disable! Maybe we should trade?
you prefer to leave your food in the microwave overnight then?
@@matthiasrandomstuff2221 😄 I'm not sure I'd go that far. For whatever reason, it's just never happened for me before, so I weight the annoyance higher than the potential benefit. It's just interesting to me when people have such different experiences regarding the same feature.
Either way, I liked your solution. I took a similar approach when rigging up a circuit to switch on/off a car outlet when the car is on/off. It's satisfying coming up with a solution to an otherwise annoying problem.
You might think about adding a buffer stage before the ADC, not sure how large the transients are but id imagine inrush currents to the microwave will be large and could wear out the input over time
I left some headroom on the adc range
@@matthiasrandomstuff2221 right, but especially with unbuffered ADC's the internal comparators can get worn excessively from out of range voltages. The inrush current from your microwave will produce large voltage spikes on the output of your current sense coil and over time this could cause damage. Best practice is to use a opamp as a transimpedance amplifier and then feed the output of that into your adc
Funny how you are using the same Notepad++ colours as I do!
I have to agree that using python for these embedded environments feels wrong, been though the same struggle where nearly all the resources are for python
It's a scale and market thing to be sure. At scale or in a professionally oriented market I'd shudder to think of resources being primarily Python, but for educational and one offs it makes a bit more sense
@@TheVoidSinger 100% I'm not obsessive or pure about these things, everything has it's place
@@TheBrick2 Didn't mean to imply it, mea culpa. I actually agree it "feels" wrong, especially coming from a professional perspective. Only in the last decade or so has the educational bent really taken hold in the electronics space. I don't see it so much as python replacing Cxy as a standard resource in the space, but more that it's outpaced it.
Nice
I like the make method of compiling programs and loading them onto microprocessors. I can't seem to figure it out for the Pico using C; so much is for Python. I've tried using your GIT but there is a lot going on. If you did a video on setting up a pi to load C programs onto the Pico I would be pumped. I have tried to get GPT to help me out and I still get errors.
Also, I love your channel and woodworking.
How fast can the current clamp be polled reliably for data with the pico? I'm having some issues with my power chair and I'm wanting to log some data since the issue is intermittent. I'd love to love poll voltage and amperage about 60 times a second but only log it to the SD card 5 times a second(at most) unless there is a sharp change in voltage/current. Then it would log 30 times a second. I'm only just getting started with the project and I may end up not actually doing it. I can't tell if my motor controller is going out on my chair or if my batteries are getting weak. It's started going into over current protect mode on small hills. I suspect it's voltage drop causing the amperage to spike. My multi-meter isn't good enough to catch it when it happens.
I'm polling iever milisecond, but the pico can go much faster than that
That panasonic microwave looks like the same one I have. If that is the same one, it uses an inverter board to allow for a smaller and MUCH lighter transformer by driving it as a higher frequency. As a safety note, you should look at its RF leakage. Mine is like an RF firehose. Please let me know if yours has this issue! If it does, What is the cause (inverter or faraday cage leakage,) and what should we do to correct them?
Haven't noticed issues with ours.
In my manual it gives a key combination to enable the beep reminder.
I think you are smart to just use notepad++ and a Makefile. Keeping it simple always pays off in the end
Honestly for small stuff it's just so much easier 👍
Nice project. Maybe it has potential for commercialization? The Mark II version could be a box that plugs directly into the outlet, with an outlet on its face for the microwave.
You can achieve literally this with any smart plug that has some automation built in, which is most of them. But where's the fun in that?
Then if you integrated a microphone into it as well, you could remotely turn the microwave on and off by making some kind of loud noise... like clapping comes to mind for no particular reason at all
You said that you had two ssh connections into your pi - would the screen command potentially help? Screen is a terminal multiplexer. I use it when ssh'ing into my Pi, start a long running task, and then ssh out again.. That long running task doesn't stop, and I can check back in again in the future to see how it's going. For your purpose, you could just have two "virtual terminals" in the same ssh session, and jump between the two. The downside is that you wouldn't be able to view them both at once - at least I don't think so, I use screen for it's most basic of basic functions
I should learn one of those tools. There's only one pi I leave long running stuff running, and that one is also running a GUI, so I just use VNC to start those. For the application here, I wanted separate windows on my PC. The window with minicom in it is always running. The cool thing is, minicom reconnects to the pico after it reboots -- a very nice setup that way!
Cool
C programming is the best choice :)
Very interesting. Tho, I doubt you will hear that piezo from any other room that has a separating wall.
consider using tmux when working on your raspberry pi over ssh
this is convenient to do in codesys
I would have put the Pico inside the oven along side the internal electronics. I would have the Pico operate the internal buzzer with the old buzzer circuit as an input to keep the old alerts. Have the Pico just keep alerting until the door is opened. Power could be stolen from the oven's logic board and the light could be monitored any number of ways. No case needed, no power cord modification, no power supply, no current sensor.
except you have to figure out all the internals of the microwave. No thanks!
I often wonder if there is a way to access the software running in products such as your microwave and make change to in improve its usability or features like this.
Is that possible to do?
I don't know. Don't ask me.
Your solution for the clamp meter looks good but another option is the Klein Tools 69409 Line Splitter 10x for about $15.
expensive bulky and ugly for this situation
Cool project, could be ported to a lot of power applications, but... Don't most microwaves have key combos to change beep behavior?
never heard of such a thing
@@matthiasrandomstuff2221 manufacturer dependent, I suppose. And probably something in a service manual, rather than an owners manual. Panasonic might have that option.
Wasn't until recently that I even thought to check service modes on appliances until I had to replace a blown cap on my dishwasher control board. Now I can put most of my appliances in debug mode :)
I love the complicated solution to parenting issues. Lol
I feel like I want to achieve the same as a Panasonic microwave enthusiast with a Homeassistant script using a plug socket power monitor :P
Great Project to keep the juices flowing. I prefer the esp8266/32 (e.g WeMos D1 Mini) for things like this, but they don't have that snazzy colored LED ;)
As a fellow embedded systems programmer, Python and Embedded just don't go together. Python will always be a glorified scripting language to me or a front-end for libraries(written in C)
You can amplify the piezo sound by attaching a polystyrene cup to it, or black it I a reflective surface, like a round inside surface in a dish or bowl. You can experiment using a cellphone playing audio to see what works best.
Would 50% power ok the microwave work for this setup? Doesnt the power get cycled in less than 100% power scenarios?
we don't use that. But at 50% power, the fan still runs in between, and I set the threshold for "microwaving" to be low enough that fann running counts as microwaving.
👍👍
Aren't most of the common python libraries just C in a trenchcoat?
I'm sure there would be a clear difference if the computational load is large enough but not at the scale most people use these for.
How does this deal with the microwave not running at full power? Usually microwaves run at a really slow PWM (tens of seconds), so it might be annoying to detect?
Between microwaving and idling when using less than power, the fan is still running. I just set the "microwavning" threshold low enough that it will consider fan running also as "microwaving"
What happens if you open the door before the timer ends? Does it still detect the current drop and low current light on state? Or does it need the true 0 state after the beeper and light is off?
opening the door turns off the microwaving function. So it detects microwaving ended and door opened, so all is good.
How do you handle the edge case if you continue to cook before opening the door.
opening the door stops the cooking. So we go from cooking to door open, so no problem.
@@matthiasrandomstuff2221 Okay, my microwave has a feature where after its done cooking you can add time and continue to cook without opening the door. Didn't know if yours is the same.
Would it be relatively easy to augment this with a scale. Basically take a tare weight of the microwave and if the weight measure is greater that means there's something in the microwave?
"easy" to you if you have never tried anything remotely similar.
@@matthiasrandomstuff2221 hah, sorry it was meant to be posed as a question (?).
And "easy" relative to the project you documented here.
That falls apart if somebody puts something on top of the microwave. Also food items often weigh _much_ less than a microwave so sensor drift would be an issue.
How hard would it be to replace a basic microwave's whole control unit with an SBC?
Also why is every microwave hinged on the left?
Very easy. For a typical microwave with a digital timer the control unit only has one input (a door sensor) and two outputs (a power relay for the MOT and one for the light/fan/turntable). Some inverter microwaves might have electronic control signals but I believe some are drop-in replacements of the MOT.
At this point, MW is just flexing on us all
👍
I've got the opposite problem, I want the microwave to just beep once and then stop, because it doesn't stop even when we open the door!
I have the feeling the people who write code for microwave ovens aren typically not great software developers.
I applaud your use of C for an embedded device. You have no idea how annoyed I am with seeing Python constantly being used for such projects.
Maple syrup in the microwave... hilarious!
just a containr with water in it
We microwave maple syrup all the time. But not the whole container. Just a small amount that we use for one meal.
I didn't know these clamps existed, I guess I could use one to pick up the signal from a spark plug then.
would not work for a spark plug.
A bit soft to use C. I would've expected it all to be done in assembly. 😄
At 09:18, we leave the mundane but still useful realm of sand (read silicon) programming of electronic micro devices for an entirely more satisfying and natural world of the wood programming the necessary enclosure. And indeed that incorporation may be necessary to pacify that slightly fanatic (rabid?) audience of (Matthias) Wandel woodwork wanters.
(Please note: No electricians tape was wasted in this production.)
Here we should perhaps also make the distinction between sand box programming style (python, java and such higher bulked up languages necessarily embedded in the safety rails of IDEs) and the more free wheeling beach sand style (c, assembler) of programming silicon.
My microwave starts being a bit smelly if I close the door immediately after cooking, so I leave it open.
But then again it automatically turns off the light after a few minutes.
Matthias, I would appreciate it if you could do a video on how to program a Arduino rev 3 and run it with and without a potimeter, please and thank you.
I forgot to mention, that it's must be on a brushless motor.