Assume two applications running on a RPi 4B, each one using a screen (connected to the HDMI ports).
Requirements:
Both applications are started at boot time.
Each application must use a specific screen (something like a screen for engine information and the other for GPS mapping).
The RPi is dedicated to running these applications.
How does one go about this? I found information on how to start an application during boot, but nothing about associating application X to display Y...
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I am currently building an app that controls a single actuator and a LED strip. The controller for the actuator and LED strip is based on an ESP32.
On the ESP32 I have used the <ESPAsyncWebServer.h>, <ESPAsyncWiFiManager.h> to set up and connect the ESP to the local wireless network. In the app I would like to send some commands to the ESP like http://<ESP32_IP>/led_set?level=<level> and
http://<ESP32_IP>/act_open and so on, this shouldn't be an issue.
Normally I would set up mDNS on the ESP and in the Flutter app, however several of the ESP controllers are already shipped to the customers. So I am looking for another way to identify the ESP.
At the moment I have used the ping_discover_network library and the ESP shows up fine on port 80. I am however not able to separate the ESP from the other devices that shows up on port 80.
Do any of you have any suggestions?
Thank you in advance
You don't have many good options. If you only want to identify a few devices which have slipped through your fingers without mDNS, you can use their MAC address as a filter. If you happen to know their individual MAC addresses, then that should be quite painless. Otherwise you'd have to look for devices with MAC OUI (first 3 bytes, usually) ranges allocated to Espressif. Espressif has several OUI ranges, but if your devices were from a single batch of ESP32 module of the same type, they'll be using the same OUI so it should be quite easy to figure out.
E.g. a batch of modules I have all start with 40:F5:20:...
Of course, if a third party installs their (unrelated) ESP32 module into the same network, you'll have a chance of identifying those as well, but such is life.
This is obviously a stop-gap measure. Make sure further devices go out of door with some identification (mDNS or otherwise).
I have written a PyQt Application that runs on my Raspberry Pi. Now I want to take it a step further and access the Application from other devices while it is running on my Pi. The Application has to be interactable, see the images.
I imagine I would have to setup the Pi as a Server (There's tutorials on the Pi website), but how do I actually access the GUI then? It's supposed to be like a remote connection but just through a web browser without installing third party software on my device.
you are thinking of pyqt as a presentation layer. it is not that.
you would have to rewrite your app as a client-server app, separating the logic from the presentation.
google for "client server programming model" for some idea's
good luck
I am new with this Pi device and just got an Pi 3 Model B. I would like to make a small project with it by turning it to become a dashboard to display some data which get from the server. To do this I have a server running on my laptop which will provide the data. Then I create an html page to draw the dashboard, I draw using highcharts tool. Finally I display the result on the Pi (connected with a monitor using HDMI cabel) by just using its web browser and access to the html page and then the result will be displayed on the monitor.
But what I realise at the end is that I just use the web browser of the Raspberry Pi to display the dashboard and this was not dealing much with the programming of the Raspberry Pi. Therefore I would like to ask that is there any other ways to program with the Pi so that it can connect with the server, get the result and then display the result in a chart as a dashboard. This sound better than my solution as using the Pi as a programming tool instead of displaying tool.
Thank you so much
I've received a project from someone that includes an Arduino (Uno) board with some sensors and lights with an USB cable and a documented protocol for communicating with this board through a COM port. It works fine with some existing code, but I need to port the whole project to a Windows RT environment using an ARM processor and including the Metro interface for the application. And it's going to be completely rewritten...
First of all, my Windows RT device does have an USB port so it can connect to the board. But the challenge is to communicate with the board to read out the sensors and manipulate the lights and I happen to have problems finding some useful libraries, tutorials or other information about how to make these work together.
This project works fine with other Windows versions, though. I just need something specific for Windows RT/ARM/Metro.
Currently it is not possible to do this on Windows RT, and here is an explanation why. As a work around I am using a standard full screen WPF application in combination with the Surface SDK for touch enable UI components. The obvious disadvantage here is that you cannot publish the app to the store.
I think that we should actually try it on a real machine instead of the rt. The surface rt is basically for documents and the internet.
You'd be better off trying all of this with a Toshiba 2032.
A PDA from about 2003.
Am I missing something glaringly obvious or is there no way to debug an iOS app which uses an external accessory that's connected via the 30-pin dock without using a bucket load of logs etc. I want to be able to use things such as breakpoints and Instruments.
Is there a way to remote debug perhaps, over Wi-Fi, Bluetooth?
Note: Yes, I asked this very recently and I deleted it because I thought I found the answer.. but the answer was only Instruments has support over Wi-Fi.. not Xcode debugging. So the question still remains...
And so...: Given that I've had no real luck finding the answer, and no one has given me an answer as yet - I take it that it is a big fat NO. :(
Makes me wonder are we just expected to magically guess where bugs occur, or log the crap out of everything while wearing out our dock connectors by continuously moving it back and forth between the device and accessory?
Time to file a bug report I guess.
At CES today, I talked to a developer from Wahoo Fitness that makes an ANT+ accessory for iPhone. They had this same problem, but found a solution.
They found a pass-through dock extender that has a mini-USB port. They used the mini-USB port for debugging while the accessory was connected.
The product they were using is http://www.cablejive.com/products/dockStubz.html
This blog talks about remote debugging iOS with a dock accessory attached
You could connect the external accessory to another iOS device (not the one tethered to the Mac running the Xcode debugger). Then tunnel all your EA framework messages from the accessory connected device to the device running the app being debugged over a pair of wifi sockets. Look at the code for tunneling accelerometer messages from a device to the iOS Simulator (a common trick for debugging game code on the Simulator) for one example of how this could be done.
After further researching, and having seen that people had to do sending strings over Wi-Fi to get around this, I'm concluding the answer is no.
I have filed a bug request for this.
In the mean time, it seems like the Wi-Fi logging, and on-device text logging will be the way to go for now.
Here's my understanding for why just the USB protocol works for some external accessories and doesn't for other external accessories. Looks like a fundamental problem, without an arbitrator, two masters can't talk to a single slave over USB, a serial Master/Slave protocol. So XCode is one master, the iPhone is the slave device. If the external accessory is a master too, one won't be able to connect the iPhone (Xcode slave) to the second master (the external accessory).
Probably the Wahoo Key for iPhone" is a slave device and that's why the dockStubz solution works for such an external accessory.
I have tested the dockStubz. It doesn't work for my external accessory. As suspected, the USB protocol can't be used to have two Master devices controlling a single slave device. Trying to hook up a Mac (Master) (via the mini USB ) & an external accessory (Master) (via the 30 pin connector) to the iPhone 4 (Slave) causes the iPhone to go in loop of connect & re-connect.
Following looks promising too, though expensive: digi.com/support/kbase/kbaseresultdetl.jsp?id=485.
Has any one tried to use USB to Ethernet connectors and use a router to route requests from two masters (XCode & External Accessory) to the slave (iPhone)? I am off to Best Buy to purchase USB to Ethernet cables and hook all three on to my IP router. Will report if it works.
This is what will be needed :
http://www.bestbuy.com/site/IOGEAR+-+USB+Ethernet+Extender/9614781.p?id=1218131339965&skuId=9614781&st=USB%20to%20Ethernet&cp=1&lp=1
http://www.frys.com/product/6103339
So connect XCode mac using the male end into the USB slot of your computer. . Use a ethernet cable to connect this to a router.
Connect the iPhone to the female part of the IO gear connector. Connect it to the router via ethernet cable.
Connect the external accessory with the male connector (Sabrent USB to Fast Ethernet Network Adapter.) Connect it to router.
I am still researching if this will work. Just ordered the parts. Will get it by Friday & will report back then.
Update:
The IOGear male end draws too much current when connected to router. Also, the female end can't charge iPhone when connected to the router even when 5V USB current supplied.
So tried to directly connect the iPhone to the USB slot of the router (used for printers). It does charge the iPhone. Also used USB to Fast Ethernet Network Adapter (BestBuy had one to connect Wii via USB) to connect the Mac to the router. It did connect to internet but couldn't find the iPhone. In the router client list I don't see any login entires for the iPhone. So this experiment was a failure unless someone have other pointers.