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Search - "gpio"
It finally hit me the other day.
I'm working on an IoT project for a late-stage ALS patient. The setup is that he has a tablet he controls with his eye movements, and he wants to be able to control furnishings in his room without relying on anyone else.
I set up a socket connection between his tablet and the Raspberry Pi. From there it was a simple matter of using GPIO to turn a lamp or fan on or off. I did the whole thing in C, even the socket programming on the Pi.
As I was finishing up the main control of the program on the Pi I realized that I need to be more certain of this than anything I've ever done before.
If something breaks, the client may be forced to go days without being able to turn his room light on, or his fan off.
Understand he is totally trapped in his own body so it's not like he can simply turn the fan off. The nursing staff are not particularly helpful and his wife is tied up a lot with work and their two small children so she can't spend all day every day doting on him.
Think of how annoying it is when you're trying to sleep and someone turns the light on in your room; now imagine you can't turn it off yourself, and it would take you about twenty minutes to tell someone to turn it off -- that is once you get their attention, again without being able to move any part of your body except your eyes.
As programmers and devs, it's a skill to do thorough testing and iron-out all the bugs. It is an entirely different experience when your client will be depending on what you're doing to drastically improve his quality of life, by being able to control his comfort level directly without relying on others -- that is, to do the simplest of tasks that we all take for granted.
Giving this man some independence back to his life is a huge honor; however, it carries the burden of knowing that I need to be damned confident in what I am doing, and that I have designed the system to recover from any catastrophe as quickly as possible.
In case you were wondering how I did it all: The Pi launches a wrapper for the socket connection on boot.
The wrapper launches the actual socket connection in a child process, then waits for it to exit. When the socket connection exits, the wrapper analyzes the cause for the exit.
If the socket connection exited safely -- by passing a special command from the tablet to the Pi -- then the wrapper exits the main function, which allows updating the Pi. If the socket connection exited unexpectedly, then the Pi reboots automatically -- which is the fastest way to return functionality and to safeguard against any resource leaks.
The socket program itself launches its own child process, which is an executable on the Pi. The data sent by the tablet is the name of the executable on the Pi. This allows a dynamic number of programs that can be controlled from the tablet, without having to reprogram the Pi, except for loding the executable onto it. If this child of the socket program fails, it will not disrupt its parent process, which is the socket program itself.13
Bought a Raspberry pi with intentions of making a kickass hacking module. Ended up blinking the LED lights from GPIO pins. How's your life?11
*makes course outline*
Management: Um yeah make the outline similar to this course from earlier
Me: Hmm, so Yocto etc.. well that'll require a good amount of research because I've got no idea what Yocto is or how I'm supposed to use it.
*researches about Yocto, prepares build VM and Raspberry Pi target, thinks of how on Earth I'd make my coworker without Raspberry Pi interface with it from across the world*
2 days later..
Management: Yeah actually we don't want Yocto. Just do simple stuff like application development, GPIO etc.
Me & co-worker: Awesome mate! That'll make things a lot easier. Except for the 2 days of lost work, but we can live with that if it's just GPIO and such.
3 days later..
Management: guys your course outline sucks. Do it all over again, we want Yocto to be in it after all.
YOU MOTHERFUCKERS!!! Why don't you behave a little bit less like a fucking client that doesn't know what they want for once?!!18
CPI, coffee programming interface. Pretty much my boss wired a Pi0 to his coffee pot somehow and uses the GPIO pins to detect when the pot is done brewing and stops heating the top, then it sends a message to him on Slack.8
*desolders Ethernet, USB and GPIO rails from Raspberry Pi to decrease height*
(Desoldering that shit from a Pi fucking sucks btw, no idea what solder or pads they use but it's garbage)
*boots up Raspbian to see whether it still works and to set things up*
Oh shit.. I need keyboard and mouse for this :') fuck me I guess... Long live planning ahead. Does there exist a KVM over TCP/IP yet? 😅20
Me, hacking the sunxi kernel to access gpio on my orange pi:
My friend: "oh, a raspberry, are you using python for that?"
Me, looking up from opcode dump: "you can use python for this?"3
This is probably dumb, but I felt genuinely let down when there were no options for facial hair for my female avatar.
I actually waited for a moment, thinking maybe it was just taking a minute to load, but then it hit me :'(5
Coders get yourself a electronics friend and electronic heads get yourself a coder.
I got a friend who studies engineering and really loves it and i do software development with a passion.
And we both love to chill with some drinks every now and then.
The result: We're currently creating a thing which fills you drinks via a button press on your phone.😁
Optional paypal payment for every drink for use at parties of course.(;5
-_- every time I use windows recently, I'm reminded of why I haven't for years... I swear, the simplest things are so freaking hard to do. It's like, windows doesn't support W, but blog post A references program B, which converts Z into Y, and after spending 3 more hours googling I find programs C and D, which convert Y into X, and then X into W. Were you able to follow along? Yeah, neither can I. The logo comes up and I immediately get PTSD and start falling down Alice's rabbit hole only to realize I've just wasted 5 hours of my life...
Unfortunately, ASUS is horrible and refuses to make even the most basic, minimally-functioning Linux drivers, or provide anybody with the resources to do it themselves, and they put everything on GPIO chips capable of frying the laptop!!! I'm so freaking done...
I feel like an adult locked in a child-safe playroom full of baby toys...31
So our new hardware guy who is being managed by our lead embedded developer had the task of designing me an expansion board for my Linux board. The Linux board uses the 40 pin expansion like the raspberry, bananna and orange pi family and as you all know there are many different types of expansion boards for this.
I said at the start come to me and tell me what you want to connect to before deciding which pin you connect to so it is less work for me with Linux board configs and drivers.............
No no no we will sort it all... erm.....
So today they come ask me if they can use an SPI port for GPIO and I am like erm... why there is plenty of GPIO...
It turns out they have been designing the board based on the pin outs of an expansion board and not the actual connector of the Linux board.. I mean seriously WTF!1
Wtf. I tought IPS isnt supposed to burn white into the screen. Fuck. I had Rpi gpio diagram on screen and bg was white. Now i have it burnt into the screen. Fuck. Well i hope 2 hours of colors switching and then white for hour will fix it. Have you had this issue ?1
So I'm taking embedded systems subject in my masters course. They have mixed this subject's content with electrical engineering and I'm a computer science graduate. Everything was perfect until I reached to GPIO board.
Wtf is this shit?
Why it has so many holes and what are they for?
What I'm supposed to do with it?
What is ground? Transistor?
Why I'm connecting to two pins only instead of the 4 pins of a button?
Thanks to pi4j i think i will pass the subject!2
Code your own damn stuff!
I am building a RFID and button controlled music player for kids.
I am using a couple of different modules for that. The one for the input was really laggy. I thought it was so laggy because of the network delay. I tinkered with it a week but it didn't improved. So I just coded my own module which was much easier to do than I thought.
It was a really rewarding to code something yourself in less than a day instead of trying to get something working for a week.
So I was changing some CSS, but the changes weren't showing.
Was it being cached? Nope
Was the selector wrong? Nope
Well it was the right file yeah? Yup
So after like 10min of scratching my head, restarting the server, etc it turns out I was checking prod instead of dev.
This isn't even the first time this has happened 😑
Guys just remember to keep your dev tab and your prod tab away from each other, like way away.8
You want to change the wifi network to which is your embedded device connected?
- The native process is broken
- ESP is in the correct state, but refuse to communicate with anything
- Restore to default doesn't work
- Flashing default firmware doesn't help
- download the whole NodeJS/NPM
- compile two perl binaries
- bump into 2 year old bug, that your Intel wifi won't connect to the ESP SoftAP
- reinstall the Intel driver, just to find out it's still not fixed
- connect the external Atheros wifi adapter
- connect that shit back to the cloud
And just after little under 4 days of fiddling with GPIO pins it finally works and communicates.2
I hate it when you actually buy a template and it turns out things only align when your images and text are a certain length.
Dear designer no, my images are not all 200 x 200. Screw you :)4
Today I made some lights turn on and off with Gpio on my Rpi and some php, really happy and I'm going to work on it cause the landing site is really ugly. Would it be appropriate to add "mechanical engineer" and additional to web developer to my resume now? 😂😂1
I told you guys that I would update you on my PiBM-5150 project. I figured out the hard way that my USB to DB-25 cable wouldn't cut it. Seems it is for printers and no matter how hard I tried it wouldn't work because of the path of the wires. After researching, it is apparent that the GPIO pins on the pi are configured for serial by default but it requires a little voltage change from TTY to RS-232. Rather than do like one of the videos I saw and solder junk to a bread board, I found a serial (rs-232) shield and 9pin output for the pi. Now, both computers are true rs-232 each. Instead of using a modem between them, I bought a null modem cable (crossover of Tx Rx signals) to interface the two machines directly. I'll update this evening to show it hopefully working.
I was having fun with GPIO recently. Now I have an RGB LED flashing in my room when my alarm clock starts ringing.
Android App sending HTTP Request when Alarm has been triggered, php starts a bash script (was too lazy to do it in php). Bash script does its job for 10 seconds.
We're looking to change the domain provider we use to register new client's domains to one that has an API.
So far it looks like it'll either be namecheap or AWS's Route 53.
We're also looking for the same thing with mail inboxes.
Do you have any recommendations / experience with either of these?
I was hoping to find a solution that would provide both the domain registration and the mailboxes with no hosting and accessible via API but I've had no such luck.
(Except for maybe two, but neither looked up to date)10
So you mainlined your phone to the point where UART is working. Amazing right ?
You flash it.
You boot it up and basically nothing happens.
You recheck the adresses and GPIO pins in device tree file. No its all correct.
Then you realize it.
The phone is old and the bootloader has no clue what dts file even is so no luck there. What do you do ?
You append the dts to the kernel image.
Isnt it wonderful that you can make 1 file from 2 and use that as kernel which then takes the dts file and uses it instead of relying on bootloader to do all the shit work for him ? Yeah it is absolutely AMAZING and saves me ton shit lot of time because if it wasnt for this i would be porting U-boot at this point which i really really dont wont to do at this point. Why not ?
Its kinda simple.
When mainlining a phone that doesnt have dts support the bootloader has to set the regulators to the correct values and shit otherwise the phone would die. And the amazing thing is that if i dont specify that regulator in dts it wont be set to anything and it will be at the value bootloader set it to. So its kinda like a safebox for me at this moment.
If i replaced it with uboot (Which i will do once the phone is working on mainline kernel) then the bootloader would not have all the regulators and it will be a shit mess and the phone would most likely die.
Isnt mainlining so much fun ? It IS.3
I have a simple task to do but I want some of you guys' input.
So I need to set up a button that when pressed will cause a video to play on a nearby TV.
- This must happen instantly (or at most with a second or two of delay)
- Video will be "self-hosted" (not on Youtube or something) and will mainly stay the same
- No idea what kind of TV I'll get to work with (might be smart, probably not)
I'm thinking a Raspberry Pi with a button connected to it's GPIO and a static image displayed on the TV when idle. That way I can also manage/maintain it remotely via SSH and it should be reliable enough but on the other hand this could be an overkill...
Post your 2 cents please and thank you :)2
Does anyone know a single-board computer like e.g. the raspberry pi that features a physical on-board audio input as well as an output?
I know that GPIO-header-boards like e.g. the hifiberry or WolframAudio (which seems somewhat deprecated by now) exist. I could probably also alternate to an USB-soundcard, but I'm curious whether someone might know a more compact solution.5
FUCK MY LIFE WHY CANT A RASPI BOOT FROM USB??! I'VE BEEN WORKING ON A PROJECT FOR IT FOR THE LAST WEEK, SPENT NIGHTS LEARNING ELECTRONIC BASICS AND GUESS WHAT? THAT FUCKING RASPIAN ON MY MICRO SD CARD IS NOT BOOTING. AND I CANT REINSTALL IT BECAUSE I HAVENT GOT AN FUCKING ADAPTER FOR THIS SHIT. I HAVENT BEEN USING A MICRO SD FOR YEARS.
AND NOW I CANT TEST MY PROGRAM BECAUSE I NEED THE RASPIS GPIO PINS :(6
I am a young dev trying my hands around in different stuff.
So I would appreciate any criticism or comments that would allow me to Learn more :) or good practices I can follow.
Here is one project where I tried to create a structured frameworkish way to write mqtt processors.
Mqtt processors are standalone apps that process mqtt requests that has to be acted upon (like add sensor data to db sent from sensor node, read from db, turn some gpio on or off if the app is on some embedded device like raspi ) etc.
This project creates a structure where you can just focus on writing subscribed topic listeners in a clean neat way. (Hopefully)6
There was a small exhibition in our school. I made a retropie arcade with the ability to play them physically with gpio.
Another one streamed video from a android phone over wifi.
He won the competition.4
Ideas I've had over the years that could pan out and be useful:
SMS-DB: Stands for SMS-Data Burst. Used to allow those with low cell signal or no data plan to transfer data between a phone and some client via the standard SMS text space. Would be slow, but would act kinda like dial-up over SMS (as mobile lines are compressed on all service levels, even LTE, so traditional dial-up wouldn't work!) I have a general idea on how packets would be laid out, but that's about it so far...
everything2PNG: Allows one to transpose any file's data into a PNG with a 3 byte per pixel (full color RGB), which allows for a "compression" of sorts (about 91, 93% on preliminary tests) AND allowing further, more efficient compression of the resulting file. (Plus... it's just kinda cool to see files transposed as PNGs.) I actually have a simple transposer to go to PNG, but can't yet go back. Large files (around 600MB) use upwards of 4GB with efficient paging and other optimizations via NumPy so far, so it's not *viable* yet, but it's coming along nicely.
RPi-GPIO Interconnection Bus: A master/slave or round robin method to allow for Raspberry Pis to communicate using GPIO, which can help free up network bandwidth in RPi cloud computing clusters. At most, this'd allow for 4 bits used for pushing to the GPIO "bus", and 4 bits used for pulling from the "bus". 8 pins total are usually unused minimum, so either 3 or 4 pins for upload, 3 or 4 for download, and potentially 1 or 2 for commands, general non-data communication, etc. I made a version of this concept using Round Robin for a client, but it was horribly slow. (I also don't have distribution rights for the code, so i'm working from scratch.) Definitely doable.
Im thinking about getting a raspberry pi 3 or an odroid-c2.
(Specs at the end)
Its to host a simple php server and maybe a gitlab server, both for personal use.
Should I go with the better performance or the better community support?
System-on-chip used : Amlogic S905
CPU: 1.5 GHz 64-bit quad-core ARM Cortex-A53
Memory: 2 GB LPDDR3 RAM at 912 MHz
Storage: MicroSDHC slot, eMMC module socket
Graphics: Mali-450 MP3
Connectivity: 4× USB 2.0, micro-USB OTG, HDMI 2.0, Gigabit Ethernet (8P8C), Infrared, 40× GPIO ports
SoC: Broadcom BCM2837
CPU: 4× ARM Cortex-A53, 1.2GHz
GPU: Broadcom VideoCore IV
RAM: 1GB LPDDR2 (900 MHz)
Networking: 10/100 Ethernet, 2.4GHz 802.11n wireless
Bluetooth: Bluetooth 4.1 Classic, Bluetooth Low Energy
GPIO: 40-pin header, populated
Ports: HDMI, 3.5mm analogue audio-video jack, 4× USB 2.0, Ethernet, Camera Serial Interface (CSI), Display Serial Interface (DSI)10
I've gotta create a bidirectional communication protocol to link 2-3 RPis over GPIO. I have between 4-5 pins for TX and 45 for RX, so each directional bus is that wide.
Even better, I have to assume 4 bit bus length unless told otherwise, since 4 to 6 pins on the GPIO are usually used for serial/UART, COM and/or 1-pin communications (for use to get a console, not to throw data down.)
The best part?
Needs to be a Python library.
i wanna die6
"Google Voice Kit - Install this image on your RPi 3B+ (or Zero depending on the kit version), pop this Hat on the GPIO pins, and press the button! It's that easy!!!"
how did this happen google
Rant! The reason. Software engineers have to take test just to get a job. Is cause there are to many hacks out there.
Me. Did you read the schematic did you see the gpio that enables the JTAG needs to be asserted to debug.
THING 1: What's JTAG debugging
THING 2: No just debug using the software.
Me: enable the JTAG or it won't work
Face palm I am so tired of helping people. We just hired who where supposedly real engineers
In every other profession there are standards. You don't see any self taught surgeons.13
I was doing stuff in my room, when I slipped on my hand and landed on my knees. I look up, and I see my Raspberry Pi's GPIO pins puncturing my hand.
Fast-forward couple of hours, I decided to post a picture of it (it wasn't bleeding or anything) on Twitter. 2 seconds pass, and my account got suspended.
I have 2 simcards: one for calls, one for unlimited data.
Twitter is trying to call me to verify the account, but I have my data phone number in the profile.
Wasted 3 hrs on this today:
-Wanted to control pi gpio pins from php web server
-shell_exec(gpio write x x) wasnt working for me
-made a python script for gpio toggling which i wanted to execute with shell_exec
-still not working. Changed permissions, changed code , did everything possible SO MANY TIMES!
-Turns out if i had added a '-g' in the gpio write command..it would have worked in the first place!
Sophomore year starting soon so I'm looking for new project (s) to complete in parallel with the studies.
Some are more design-y and some more backend-y but I recently started getting better at designing so :)
1) Learn some fragment shader stuff. I've always been messing around with graphics and have a game on steam, so I think that's a good idea to be paired with signal processing.
2) Reactive web services. Preferably with spring-boot or vert.x but
3) I would also like to dive into golang (and make some reactive thing with it)
4) WebAssembly seems nice... But I got some concerns
5) exercise making wireframes -> CSS (with some js)
6) I've never really done any real backed work with nodejs, except serving and aot compiling js, or doing gulp tasks
7) Implementing a whole project, or a fraction of it as serverless on aws
* I'm definitely going to use a couple very simple services to make a docker swarm with load balancing, etc, just because I know how everything works but got no practical knowledge
8) Design an esports jersey for the university department I'm in (shouldn't take long)
So what do you guys think? Recommendations are welcome :)
P.S. last year in review:
> A webapp running on a raspberry pi powering a reflex testing game on gpio (java/spring-boot , codename: buttonmasher)
> small Elastic search cluster to monitor some random university servers through kibana dashboards
> laser tracking on wall of *any* colour and variable light conditions via a webcam (opencv) , controlling the mouse pointer, whether you run it against a projector or any wall
> Various random Photoshop stuff
Using Sudo to run a node script that interacts with GPIO pins on Ubuntu (Minnowboard). The permissions suck.