I plan to extend the range of my Wifi with my Notebook. - My question to this, is it possible to build a wireless repeater with only one NIC? or do I really need at least two NICs, one for being logged in and receiving the packets and the other for extending the WiFi/Signal. - Actually, what I wanna do is, using my laptop as a WiFi-Repeater, but only with the built-in NIC, no second one.
I've searched the net already but found nothing about the functionality of a WiFi-Repeater and if they have two NICs integrated.
Hope you guys can enlight me ;)
EDIT(added schemes):
Possibility A
Possibility B
What can be achieved with an AP capable Chip/Firmware, for instance, the Ath9k.
You can't turn laptop's WiFi into range extender, since I believe it requires a special WiFi chip firmware and a special configuration of antenna(s).
However, you might try to look on the internet if WiFi chip you have supports AP mode in firmware (not all manufacturers provides that), and if yes, you can set up the access point with the same SSID. In this case your WiFi clients will roam from one AP to another. Of course, this kind of setup requires Ethernet cable attached to your laptop.
Related
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 want to make a network camera, stm32 through the camera to collect images, and then sent to the server through the WIFI module. As 1 second need to transfer a lot of data, so I would like to use the USB interface wifi module program to achieve. Or what better solution to achieve.
Thank you!
I think that you have no idea how the USB works.
You have a couple solutions.
Use a wifi module with SPI interface.
Use a SOC like CC3200.L
Use ESPxxxx module or similar (RTL8710)
You can of course try to use STM with host usb interface, but you will have to implement the USB host stack + driver for USB wifi module + network stack (eg TCP/IP stack). But it is quite complicated as the STM ones are not very good, there are some better paid ones - but expensive. USB host is not easy to implement.
If you want to go along the "networking over USB" path on STM32 (and I'm assuming you're not planning to buy any commercial drivers) it's going to be rough for you.
When it comes to USB, vast majority of the WiFi dongle drivers are proprietary and unless you're on an operating system such as Windows or Linux you're out of luck, unless you want to for the reverse engineering or porting at least parts of the drivers from Linux. With the USB you can think of using the USB-ECM (ethernet over USB) class, but two things here. One - ST doesn't provide any free implementations of this class so you're down do searching for it or implementing it yourself. After a bit of googling I've found one instance of this on githbu, although I havent tested it myself. Second thing - this is no longer wireless as you'll need to be connected to some kind of host providing internet connection, at which point it's probably better to not use USB-ECM and networking at all and just send data using a class that can be implemented easily (USB-CDC or USB-HID). I'm a bit worried about the throughput here.
You can also try to find WiFi modules that are connected over other interface. Generally those modules are connected over UART, some over SPI. This way, integrating it with the TCP/IP stack will also be up to you, at least when it comes to implementing the WiFi module protocol (most likely AT-commands) and implementing network interface so that the stack can "talk" to it. In this approach, I'm almost sure that you'll lack the throughput required for your application.
Personally I'd strongly suggest trying Ethernet if that's an option for you. It's going to be highest bandwidth (which you're going to need), plus it's most "out of the box". There's multiple projects implementing various applications using a free LWIP stack over this interface, including examples generated by ST's CubeMX.
There are free projects/examples of wol (wake on LAN) for iOS?
I've found this one [openwol][1] but it's old and has no signs of recents updates.
Also I've been digging on it and it's not working as expected, the main purpose of it is wake a computer but it's not working. I've spent some time on it and still no work.
Maybe there are other examples or someone else may join on me and solve/update this code to work?
Wake-on-LAN generally doesn't work for machines on wireless networks, as the wireless hardware is typically powered down when the machine is off or asleep -- it's usually only supported for wired Ethernet. As such, wake-on-LAN is unlikely to give acceptable results on an iOS device, as it'll only work for some specific network configurations (i.e, networks where the wireless segment is bridged to a wired segment that the target system is connected to).
I'm looking to connect my iPhone to an RS-232 serial device via Bluetooth. Has anyone implemented this successfully and can offer advice on hardware to use? It's kind of tricky because of the need for the Apple Authentication Processor with the device. The best potential device I've found is this guy but it only comes in an embedded package, its serial port interface is just logic-level UART rather than line-level RS-232, and I can't find a supplier with it in stock.
Any thoughts would be appreciated.
I'm considering just using WiFi to serial instead, but please ignore that possibility for the purposes of this question.
most of the question was answered by yourself already.
Basically you have 5 (+2) choices.
Join the MFi program. This might be hard to impossible if you are not part of a at least mid-size company.
Buy the OEM Bluetooth Module. I'm not sure if this is even allowed by the apple policies.
Use WiFi. Keep in mind that you want to use a wifi chipset that can act as at least ad-hoc access point. Those chipsets are quite expensive, and you have to think of a way to join existing networks (customers don't want to leave their home network to use your product). This will add a lot of cost to the BOM of your device.
Jailbreak might be an option. I never tried to use accessories with a jailbreak, so I don't know if it's possible to use bluetooth without authentication.
Work with a company that is member of the MFi program.
(Maybe an option, and depending of the speed you want to have via RS232: Eventually you can convert the audio output of the head-phone jack to RS232 levels and vice versa)
(Not really an option: develop for Android and do whatever you want)
If you jailbreak your device, you can use BTstack.org (disclaimer: I'm the author of BTstack) to connect to a Bluetooth device that supports the Serial Port Profile. You can get Bluetooth Modules that implement SPP and provide UART level output. As David R. above points out, you then need a UART to RS232 converter, e.g. the MAX232.
Ok. Another option. There are one or two companies that sell RS232 cables for iOS, eg. Skywire here: http://www.southernstars.com/products/skywire/index.html
Then, you could uses a Bluetooth RS232 extender, which consists of a RS232-to-SPP and a SPP-to-RS232 pair. Ugly, but within Apple's rules.
Well. It seems like my answer could be something you didnt ask for.
But the guy you referred to is the answer. Buy his product and you are good to go, all you need is a MAX232 chip. Converts logic level UART to RS232.
the diffrence high + voltage low zero voltage is converted to high +~10volts low -~10volts.
I use the MAX232 chip with my microprocessor, that uses logic level USART to communicate over RS232.
There is a lot of tutorials out there explaining how to hook things up.
This product works: https://serialio.com/product/bluetooth-serial-adapter/bluesnap-smart-bluetooth-40-ble-rs232-adapter
The only downside is that the adapter requires power.
It should be possibly I would think to create something in the middle that accept the bluetooth commands and convert them to serial, similar to what this does with TCP connections: https://www.npmjs.com/package/stellar-socks
I need a product to simulate network latency for testing mobile applications (in particular iphone and android). I plan to set up a wifi router connected to a linux box, and write a number of scripts to approximate different types of connectivity issues.
So far, I've taken a cursory look at Netem and ns-2 (or its offspring ns-3). Netem looks very easy to deploy and configure, but they both look like they'll require some in-depth investigation.
Does anyone have positive/negative experiences with either of those solutions that they could share? Or maybe used a different solution for this problem?
If anyone comes here looking for tips, I've found a solution that seems to work well.
Ubuntu comes with Netem installed, so I went ahead and just made use of that. Basically, I got a computer with two ethernet ports, forwarded one to the other and applied Netem latency settings to the connection. Then I attached a wireless router to one, and LAN to the other. Netem lets me play with all kinds of latency and packet loss settings.
Btw, I also tried to use a few different laptops and set the internal wireless card up as an ad-hoc wireless router. I got it working for the most part, but finding a laptop with an internal wireless card that plays nice with ad-hoc in Linux is tricky at best... can't recommend it.