How to connect to multiple wifi networks using Python? - connection

In my project I want to implement an acces control system using Python. I have a Spycam which is connected to a Raspberry Pi 4 using wifi protocol. I want to insert in my system an arduino which also communicates with the Raspberry on wifi protocol.
I am using this code to connect to the camera(Simplest way to connect WiFi python), but how can I manage that my Raspberry could connect to both at the same time?

You can use the Arduino IDE. There is sample code that you can use to run an arduino in client mode.
PLease give more infos about the arduino and its function.

Configure the Raspbi as host and connect the cam and arduino as clients.

Related

ESP32 as main controller and ESP8266 as client

I am making a project in which I want to use ESP32 as the main controller and ESP8266 as client(for collecting data from the sensors).
I want to use the MQTT protocol and send all the data to the Ubidots platform as shown in the attached diagram.
ESP32 and ESP8266 will be connected to Mobile Hotspot.
My question is whether ESP32 as the main controller will work in station mode and ESP8266 in AP mode or opposite? Or in which they can work? (It is a kind of basic question)
Because I have to specify the mode in the code in Arduino IDE.
Like this I want my system to work
According to what you described, you're right. The station would be the ESP32, and your APs the multiple ESP8266 configured; the ESP32 will serve you as a gateway and the ESP8266 as nodes.
This guide can serve as a reference for your project. The only thing you must replace is the WiFi library required by the ESP8266 along with the necessary configurations.
Once you have established the communication between the devices, you can refer to this guide to send your data from your ESP32 to Ubidots over MQTT.

How to connect rfid reader to raspberry pi using wifi?

I am working on a tracking project.
I want to connect several rfid reader(any reader HF,UHF) to Raspberry pi using wifi. is it possible?
It depends of your reader and its capabilities.
Usually readers have Ethernet port but does not support wifi by their own.
So your first task is to connect reader to pc using Ethernet cable and make it work as you like.
Then you need to make your program work on raspberry pi.
Finally you can plug your reader to wifi router. Connect Pi to the same network using wifi dongle and here you go, you have wireless reader.

Real-time data from Raspberry Pi to iPhone

I recently have not much experiance about working with a raspberry.
I need to send real-time data from my Raspberry Pi 2 Model B to an iPhone. The Raspberry will get the internet connection via UMTS stick.
I thought about a websocket but I didn't find any information what websocket would be the best and how to config it.
So is there anyone who already has a solution about it?
Thank you!
WebSocket requires a WebSocket (WS) server or a webserver that understands the WebSocket protocol as defined by the IETF. So for a RPi to talk directly to your iPhone, one of the devices has to have a WS server... which is not likely.
There are a couple of possible alternatives (there are certainly others). You could send data from the RPi to an external server that hosts a WS-capable server which then forwards that data to your iPhone, either thru a native app or a web browser. The data is logically transmitted between the two devices, but physically sent using an external service to coordinate the two. Visit http://goo.gl/Utg0dU to see data exchanged between an RPi and an iPhone using web messaging (src available).
Another possible alternative is to use Bluetooth to send data directly from the RPi to the iPhone. Being a Java dude, I know you can run a JVM on the RPI and I know there's a Java bluetooth API, and obviously the iPhone supports bluetooth, so its definitely do-able with a JVM. A quick Google shows plenty of support for bluetooth on the RPi with other languages. So you're good with this approach too.
If the Raspberry Pi is connected to the Internet with a public IP Address (I guess it doesn't since it uses UMTS) then you can setup a TCP Listener where the iPhone will connect to. If it doesn't and you can do Port Forwarding (I guess you can't) then you can forward the TCP port to the Raspberry Pi. The above examples also work with an HTTP server.
If the iPhone is near the Raspberry Pi and you're writing an app for the iPhone you can use a Bluetooth transceiver on the Pi to communicate.
If you can't do any of this you may need a third server with a public IP where both devices will connect to and the server will relay all connections from one device to the other.
In general, it would help if you could describe a little bit better what you want to achieve and the network topology involved so we can provide more specific answers.

Redpark's L2-NET not able to connect using Redsocket SDK

I have purchased two Redpark's L2-NET cables and tried to test the basic connectivity using the examples provided in RedSocket SDK but its not able to connect.Can someone help me in understanding the exact process to establish a successful communication between my ipad/iphone and Ethernet port using Lightening to Ethernet cable.
The reason is my iPad IP&subnet and my machine IP&subnet are not matching.

Wired connection from iPhone to Raspberry Pi

I would like to build an application on my iPhone that connects to my raspberry Pi. Because these are going to be in close proximity (next to each other), I'd like to use the wired connection (lightning port to USB) to communicate. Is this possible or must I use wireless technologies? My assumption is that wired would be better as it ensures a connection and would be faster, however, I am open to be corrected.
This is related to a hobbyist project where I want to access a raspberry pi sensor on my iphone. The sensor (and Pi) will be next to the iphone. I'm building a custom weird case to combine them.
Any thoughts much appreciated.
Thanks
Iain
For communication with peripheral devices (Raspberry Pi for example) you have several alternatives.
UART via 30-pin or lightning connector (MFi needed)
USB via 30-pin or lightning connector (MFi needed)
Quick start: Microchip's development kits. This module can prolong communication to RPi or you can try to implement the Accessory stack (and communication with authentification chip) to RPi itself.
FSK or similar modulated-audio communication via audio-jack (no MFi needed)
You would have to implement hardware FSK modem on the RPi side and a software one on the iOS side. It is a bit tricky but by no means impossible.
Of course you could implement software modem on the RPi side, too. But since RPi doesn't have audio input you would have to use an USB audio card or something. Or complicate your life trying to sample an analog pin fast enough.
User not really Jake made a quite impressive list of links on this topic here on SO.
Bluetooth as an External Accessory (MFi needed)
Quick start: RN-41/42-APL
Easy to use Bluetooth stack. Communication with authentification chip is handled by the BT module. Note that when communicating with iOS devices data troughput is not much better than when using BLE modules.
Bluetooth as a BLE module (no MFi needed)
Data troughput not much worse then the old BT. Implementing the communication might be a bit more tricky code-wise. This module seems interesting.
WiFi communication (no MFi needed)
WiFi might be a good choice. But for your device and iOS device to be able to find eachother you will need either static IP (for the server device) or minimal Zeroconf (Bonjour) implementation.
When using WiFi you can go either with infrastructure network (using external Access Point) or you could go with AdHoc (created by your device). Later seems promising but be careful - iOS7 & AdHoc network don't seem to work well together yet.
With WiFi you have many modules to choose from. A simpler to use would be a module like RN-XV WiFly Module. TCP stack is already implemented in the module - you can use simple UART communication. I'm not sure how to implement Zeroconf on this one.
Or there are raw WiFi modules like MRF24WG0MA/MB. They are stable and reliable and they can be used on home-etched PCB. Downside for RPi user would be that you would almost certainly need an PIC24 or something between the RPi and MRF24W. Microchip provides free TCP/IP stack for their microcontrollers and this stack includes Zeroconf.
And the easiest way: you could simply use a WiFi dongle (with RPi) for communication. Zeroconf should be easy enough to implement on the RPi - and it's not even needed at the begining if you are ok with assigning static IP to the RPi (if it acts as a server).
This is not possible without signing up for apples MFI program. You have to pay and sign a bunch of NDA's.
https://developer.apple.com/programs/mfi/
You can use other methods, like bluetooth and connection over the audio port.
While #RokJarc's answer is pretty complete, I've also had success with both wired (lightning to usb) and wireless connections using iOS's personal hotspot. Here are the steps:
For wired, on the Pi, install ipheth-utils:
sudo apt-get install ipheth-utils
And add an eth1 network interface by editing /etc/network/interfaces to include:
allow-hotplug eth1
iface eth1 inet manual
For wireless, make sure /etc/network/interfaces has a wireless network entry such as:
allow-hotplug wlan0
iface wlan0 inet manual
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
If you are using wpa_supplicant and add a network entry for the iPhone's hotspot in /etc/wpa_supplicant/wpa_supplicant.conf:
network={
ssid="Banana Phone"
psk="ring ring ring"
key_mgmt=WPA-PSK
id_str="banana"
priority=3
}
The ssid should be the name of the phone from Settings -> General -> About -> Name and the password should come from the personal hotspot screen.
Now start the personal hotspot on your phone. The pi should automatically connect when connected by a usb to lighting cable or using wifi. After connecting, the pi should be assigned an ip somewhere in 172.20.10.x. You can run ifconfig on the pi to figure out which one. (I believe that you should be able to define a static ip here but haven't messed around with that yet)
From there, you can connect another computer to the hotspot and ssh into the pi using the 172.20.10.x ip or even ssh directly from the phone.
In my personal testing, latency over lightning is consistently low and I've used this on both a Raspberry Pi Two and Raspberry Pi Zero for streaming realtime mjpeg video from two cameras to a VR headset. In this scheme, the network is a fairly small source of the 100ms or so latency. The experience is not Vive quality of course, but it is still usable and the iPhone + Pi combo provides lots of fun hacking opportunities
It's possible to do this with Mfi.You can run usbmuxd service on your Raspberry Pi. The usbmuxd will transfer the USB data into socket packets. Your iOS App also need to implement the same protocol to rx/tx the data from/to your Raspberry Pi.
David House has already made this work. https://github.com/davidahouse/PiTalk

Resources