I need to know IF a Raspberry Pi can drive more than one display at a time,
and if it can, WHERE can I find more info on how to do this?
I want to eventually drive six(6) separate displays. Not to, say, stream a different movie on each one of the 6, but I would like to learn theoretically if I can drive all 6, each with a different software-generated animation at what I expect will be smaller resolution
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I bought a USB stick and put like 700 songs on it, so that I can plug it into my car radio, put it on shuffle and never get tired of listening to the same songs over and over again.
Turns out the car radio stops at (of course) 256 songs, so it will not play the ones with a higher ID than that.
Now I thought it would be cool to have like a Raspberry Pi where I plug the USB stick in, hit a button and the songs on it just get random names. That way the first 256 songs will be different every time I do it.
I already worked with Raspberrys, so I would know how to do that, but I honestly don't want to buy a Raspberry Pi just for that. Is there a smaller, cheaper option to achieve the same? I have an Arduino nano, but that won't work, right?
If you have a smartphone you can use OTG cables. That way you can read your usb stick to your smartphone and make a small script or app for your device to randomise the names
I am creating a simple car dashboard cluster using a Raspberry Pi 4 with a 7in screen and using an 8 channel ADC hat and the GPIO pins for sensor input.
The GPIO pins will be used to read the state of various switches in the car using a step down converter so that when a switch is on 12v from that switch will be converted to 3.3V and send to a GPIO pin so it will be high.
The ADC will be used to read the values of various 5V sensors in the car like oil pressure, coolant temp etc.
The screen is a basic HDMI 7in screen with the Pi mounted behind it and I plan to 3D print a new gauge cluster bezel to fit everything into the stock location. I have a Mausberry power controller so that the Pi will turn on with key on and turn off again with key off. I have modified the Pi so it boots from SSD and starts up pretty quickly.
I have used simple Python programs to read the data from the ADC over i2c and the GPIO pins and output it, no issues there. I have found a nice Javascript based library called Justgage which looks like a great way to display my data in a simple HTML page and have designed my page layout with the various gauges and lights that will eventually have the data read from the ADC or GPIO pins.
What I need some advice on is how best to architect the overall solution, I have all the various parts but need to integrate them. I want to minimise the amount of software running on the Pi so it boots quickly.
At the moment when the Pi boots it auto loads Chromium and opens my page I have created but I need a method to be able to read the i2c and GPIO data and then refresh the elements in the HTML page. The Justgage library supports refreshing the data so that I don't have to refresh the page and would like a method to read the data every second or so and then call the Justgage refresh function.
All the examples of this sort of model I can see online use a webserver running on the Pi but as the screen is directly connected to the Pi I don't actually need a webserver and would like to minimise the amount of software running for reliability and boot times.
Sorry for the long first post and appreciate any guidance. Happy to post the HTML if that would be of any help.
Cheers
Matt.
I'm a developer for different mobile and backend systems and pretty new to network and hardware stuff. I want to build a system/network with 6 cameras placed 100m away in the field, which I want to control with a web interface. I know how to build such interfaces, but I have no clue how to connect the hardware. I thought about the following:
I need 6 cameras(*infos added below) standing side by side with ca. 1.5m space between. These should be connected to a switch, so a 100m wire (USB or LAN, I prefer LAN) goes to a RPI which can setup the web interface controlling the cameras like ".../whatever/camera-slot-ip-or-number".
As I said in the introduction, I have no clue how to start, because actually webcams using USB as a std, but does they provide wake on LAN features? Or is it better to do it with 6 USB-cams and several RPIs?
I hope someone with a better hardware understanding can help me.
Thanks a lot
Specification for the cameras:
HD is not needed, but it should recognize a 0,5cm round hole in a 50x50cm area properly. The distance between camera and object is 7-10m A color image should transmitted, but there only 2 main-colors.
EDIT:
draft 2.0:
Piping USB through a 100m cable is not easily going to work.
Some models of USB cameras can be used with the Raspberry pi, but the performance (speed of taking a picture, and image quality too) are better with the 'native' raspberry pi camera.
The Pi also has a built-in H.264 video encoder, so you can stream live video with relative ease if you want to. A quick and brute way of doing that is to pipe the output from the built-in raspivid application to your own application that then handles flow control and pipes the data further to a socket.
If wifi does nto work for you, then you could pick some other raspberry pi model with an ethernet interface and go that way.
Also, the cost of additional Raspberry Pis (especially the zero w) is so low that the easiest and most cost efficient thing might just be to one raspberry pi camera on 6 raspberry pi's. If connecting them with Wifi works in your application, you can use the Zero W model and then you just need to feed power to them via cable.
Thank you for the updated information. I am pretty much in agreement, I think, with Sami's answer but wanted to add a few more details that are a bit big and unwieldy for a comment.
If you look across the top of your diagram, you have 6 stations at 1.5m intervals, so the width of your diagram is 7.5m. That is easily within wifi range so I am thinking a wifi access point on any of the 6 stations and a 100m Cat 6 Ethernet cable down the length of your diagram to the front-end.
As your processing doesn't sound too involved, you can likely get away with just a Raspberry Pi Zero W and a v2 camera at each station and save a fair bit of money vis-à-vis Raspberry Pi 3B+.
One thing that does concern me is looking for 0.5cm from 7-10m. The lens on the Raspberry Pi camera is pretty wide angle and a 0.5cm hole is going to be awfully small at 10m in a wide angle shot unless at very high resolution. I haven't done the maths, but I think you will be looking for a telephoto lens if such a thing exists... the maths now follows.
The horizontal field of view (FOV) of v2 camera is 62 degrees, so half that is 31 degrees and the camera is 1000cm away. So:
tan(31 degrees) = half the FOV width / 1000
So, at 10m you will get 1200cm of stuff across your image and that will be imaged by 3,280 pixels on the sensor if you shoot at the very highest resolution. So, each pixel in your image will correspond to an area 0.3cm wide whereas you are looking for holes 0.5cm wide - so it will be pretty marginal as to whether you can make it out... maths is subject to revision after a glass of wine later.
I'm trying to get to work a raspberry pi 0 W and a pervasive display eink screen together.
But, every time when the screen refresh, it reboots the pi 0. Software works great on a RPi3 but not on Rpi0w with Raspbian Lite.
Here is the soft : EpaperDisplay
Here is the screen : Screen
There is no log in /var/log/messages, neither in /var/log/syslog. Every time it reboots, it's erasing history, logs ...
If this was a software issue, you would probably see something in the logs (or you'd at least see a kernel panic message on the console in the HDMI output if you have a screen connected there).
If you have nothing in the HDMI screen when the pi crashes, I'd suspect that the display is using more power than your power supply can provide. Try with a PSU with a higher ampere rating.
If a better power supply does not help, it can be that the display sucks too much 3.3v from the raspberry pi than the zero can provide. In that case you should try feeding the display via a separate 3.3v regulator.
I've seen a lot of projects, tutorials and how-to's on the web regarding the Raspberry Pi.
I've just received my first Pi in the mail, and I can't wait to get tinkering with it.
Of course, doing any of these things is going to be a difficult process, however, as my experience with the Pi is next to none, I wondered about the capabilities of what I want to do with my first major project.
I'd like to be able to build an on-board computer for my car. I've seen several projects regarding this, and I've seen some good guides online.
However, none that I have seen will do EVERYTHING that I can think of....
I'm assuming that my 8GB SD card will be limited to only a selection of these specifications, however, here's a list of what I'd like the solution to be capable of, and if anyone knows any reason why this isn't possible, please give me a heads up :)
So...
I'd like a front-end GUI (on a 7" touchscreen monitor) with a menu to navigate the options, which will include
From this menu, I'd like to be able to select (and of course, run) the following:
Media center (I've seen things like XBMC etc.) - I'd like this to be capable of taking over the radio unit and playign mp3's etc (possibly from my iphone!?)
GPS/SatNav - I don't know how possible this is and I assume i'd need a 3G card or something...
Reverse parking camera (stick a webcam in the rear view window) etc (I've seen good tutorials for this)
Connect my phone with a bluetooth thingy(?) so that I can add a USB mic and play the receiver audio through my speakers (acting as a hands free kit)
I'll add more ideas too...
I'm not questioning if each of these individual specifications are possible, I am asking if they are all possible through one solution as a whole, with a GUI to navigate through them?
Thanks for any help.
Cal.
It is all possible, all in one bundle. 8gb is more than enough for everything, it'll only limit your music collection. The only question is: how much work are you able/capable of doing. That will be the limiting factor, not your Pi.
Short answer is yes, all exist and the pi can handle it. But you'll be writing a lot of custom software to make them interoperate.