I managed to send data from an iphone to an xbee wifi module using an infrastructure setup with the asyncudpsocket framework from github. (iphone->modem->xbee on helicopter) Had some serious delay problems with this so I thougt about creating an ad-hoc, point-to-point connection. Now with some fiddling the xbee module shows up on the iphone's hotspot list and can connect to it. But now what? Should it work with the same application as it did during the infrastructure setup (it doesn't at the moment) or there's something else I need to do first? Any help is appreciated.
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I've been tasked with figuring out how to get a mobile app to communicate with an MCU then in turn control a stepper motor. Right now I'm trying to get the WiFi module (ESP8266-01) and MCU (NUCLEO-F030R8) to play nice with each other. The catch is I have little to no experience and no education in this field. The closest experience I have is simple Arduino sketches from years ago (IE photo-resistor values driving a stepper motor) and making desktop applications with C#. I am using STM32CubeIDE but if there's a better option I can switch to that.
What I would very much like help on is send and receive simple data between a smartphone and the MCU via the WiFi module. I've read through documentation and other questions but still don't exactly know where to start.
I understand this is probably a large topic in its own right and a short blurb on the internet won't do it (and undoubtedly its multiple subcategories) justice. But I might as well ask.
Sorry if this is too much and thank you in advance.
This project would involve making the following connections.
The UART connection between STM32 and ESP8266.
The WiFi connection between ESP8266 and the mobile.
The application layer protocol between ESP8266 and the application running on the mobile.
For 1, you can actually program the ESP8266 using Arduino IDE and simply connect the UART TX/RX pins of ESP8266 with RX/TX pins of STM32 respectively. You can create a test project in which ESP8266 sends data to STM32 over UART to verify this connection.
For 2, you need to consider the wifi network mode i.e identify whether the wifi connection is going to be ad-hoc (mobile connects to ESP8266 directly) or in infrastructure mode (mobile and ESP8266 connected via a shared access point). You can configure the ESP8266 in both modes. You just have to program the SSID and password of the Wifi network in the ESP8266 (in case of ad-hoc, it is the SSID of the network advertised by ESP8266 and in the infrastructure mode, it is the SSID of the common AP). This wifi functionality is also easily programmable in Arduino IDE for ESP8266.
Finally, once the physical connection has been established between the ESP8266 and mobile device, you need an application-level protocol to connect the application running on the mobile with the ESP8266. You can either use socket connection between ESP8266 and mobile application or use a higher-level communication protocol for IoT devices like MQTT, which is also available in the Arduino IDE.
Final connection diagram could be something like this:
application -> mqtt msgs -> wifi packets -> esp8266 recv pkts -> parse mqtt msgs -> forward data to STM32 over UART
I need to communicate my app with 2 devices. A restriction is that I can't use a server but all iOS devices will be in one Wi-Fi network. What options do I have? How I can send a message to another copy of my app running on another device?
I dont know whether its a correct approach or not but as you cannot use server,so the approach i can think of is we can create a socket connection using TCP/IP or UDP(based on reliability) for data exchange.
I dont think you can communicate between 2 devices running the same application without having some kind of server application in-between.
Even if you could find the other device over the WIFI I dont think you can tell if the other device is running the app or not.
I think you may be referring to MultipeerConnectivity
The Multipeer Connectivity framework provides support for discovering
services provided by nearby iOS devices using infrastructure Wi-Fi
networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks and
subsequently communicating with those services by sending
message-based data, streaming data, and resources (such as files).
Source: https://developer.apple.com/library/ios/documentation/MultipeerConnectivity/Reference/MultipeerConnectivityFramework/
Apple Sample:
https://developer.apple.com/library/ios/samplecode/MultipeerGroupChat/Introduction/Intro.html
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.
How do apps like Apple's "Remote" app control mac applications and send data?
is this via php with exec() commands or some other method? and how would I do it in c?
Also, how fast is this rate of transfer (can I use it to send real-time data like streaming video or audio?)
thanks to anyone who cares to enlighten me on this issue :-)
Apps generally communicate using a TCP/IP based protocol and the wireless LAN connection (the iPhone also has Bluetooth). In the case of the Remote app the communication is via with the Digital Audio Control Protocol. iTunes implements DACP so the Remote app can control it. Other common protocols are HTTP and FTP. There are classes in the iPhone SDK to connect to noth HTTP and FTP servers. There is also the Cocoa HTTP Server project which allows the iPhone to act as a HTTP server.
iPhone apps can also use Bonjour/mDNS/zeroconfig (they're different names for the same technology) so that the user doesn't have to be concerned with configuring IP address'.
The data transfer rate of the wireless connection is faster enough to stream video.
many of these remote applications work by installing client software on the computer and establishing a network connection. In the case of Apple's remote software, the client software is built into the networking capabilities of iTunes. You must authenticate using your iTunes sign in and be on local wifi.
The third party app "intelliremote" works very similarly only has it's own client software to install and can work across a WAN with proper port forwarding enabled on your network.
I haven't encountered any realtime streaming options as most of these utilities are designed to pass control messages and meta-info on media files.
I am looking to develop an iPhone application that will require point-to-point WiFi communications on an iPhone. I would like to use the WiFi interface and have the application stream between the phone and a WiFi device. Does anyone have some experience with this? Is it even possible? I know there is a discovery application but I am looking for something a little more robust.
As far as I know (as the SDK stands now), the only thing available is communication over the existing network connection. The SDK doesn't allow for setting up wireless network connections, or creating ad-hoc networks. I believe the only way to join or create wifi networks is through the settings app.