So I was curious if this is possible at all. Currently i have a program running in a micro controller (digi rabbit) that reads SPI data from a chip. I also have TCP/IP protocol set in this program so it sends the SPI data to the server. Microcontroller is programmed in C. Server is in java. I convert SPI data into string and send it over, the server reads the raw data.
But i wanted to know if there is a way that I can read the data from Ethernet port. So what i want is one end of cat 5 cable on micro controller and the other on Ethernet port of the computer. Just for testing purposes that micro controller port and everything is installed properly, before i turn on the server. I am not that experienced with networking. So if anyone can point to a blog, or any tips that would be great. My question is how would i go about it?
Thank You
What you want to do is called raw Ethernet. Of course this can be done.
On the microcontroller side you need to follow its Ethernet controller datasheet to send out and receive packets. On the PC side this is a bit more complicated and depends on the OS that is running on the PC. On Windows you can use the WinPcap driver to send and receive raw Ethernet packets.
Be aware, that both Ethernet controllers, the one on the PC and the one on the microcontroller, filter all incoming packets that do not contain the receivers MAC address or any multicast/broadcast address. For a simple check the broadcast address (all address bits are 1) will do.
Also note, that the OS on your PC will transmit all kind of packets as soon as the link is established. So you may use a unique protocol identifier in the type field of your raw Ethernet frame. Check Wikipedia's article about Ethernet frames. Btw. don't get confused. You only need to send MAC-adresses, Ethertype and the payload. Everything else, like the CRC, preamble etc., is added by the Ethernet controller automatically.
Related
My question is regarding an ESP8266 board and the ESP-touch technology.
ESP-touch uses the length field of a UDP package to broadcast wifi ID and PW through a device (like a smartphone) to the chip (like in my case ESP 8266).
I want to turn this around, more specifically:
I want the ESP8266 chip to broadcast UDP packets with some sort of identifier-number in the length field of the UDP packet, without beeing connected to any wifi connection. Then these UDP packets are recieved by an app on a smartphone so the identifier-number can be extracted and used on the smartphone.
I am relatively new to this topic and do not know if this can work.
When I try to find any information online they all say that the first step is to connect the chip to a wifi. But I don't want that. The smartphone and the chip don't know each other and are not connected in any way. So I want this type of "broadcasting" so that the smartphone can recieve the package without really beeing connected to the chip.
I guess there must be some way to make it function like I explained above, but I can't find a way how this can work.
I don't need the chip to send UDP packets explicitely, it can be any type of package. I took UDP packet as an example because there is already the ESP-touch technology which is more or less similar.
The important thing is that the package that I send has a field where I can put some identifier-number in (not encrypted), which can then be recieved by another device like a smartphone where this identifier-number is extracted.
For clarification: I don't need to use ESP touch or anything related to that. I only stated this technology as an example. I just want to achieve the behavior stated above and in the picture! :)
This is an example picture how I want it to work:
No, it's not possible to send any packages without being connected to the network. ESP-touch or TI Smart Config or similar technologies utilize Monitor mode. As the name suggests, in this mode one can listen for packages, but can't send them.
ESPNOW provides data flow between ESP devices without connections via router. It is another feature of the Espressive API. There are tutorials for ESP8266 and ESP32...
https://randomnerdtutorials.com/esp-now-esp8266-nodemcu-arduino-ide/ .. https://www.instructables.com/ESP32-With-ESP-Now-Protocol/
I'm doing a security analysis project on an IoT device that uses an unencrypted BLE connection (with ATT protocol) and I want to spoof an individual BLE packet with the source address of an already connected device. Is there some tool or API that would allow me to do this easily? I've already tried gatttool and spooftooph but they seem to be connection based and don't allow you to send out single packets with modified fields (as far as I could tell).
You will need some hardware where you can access the radio peripheral directly. What you basically need to do is to find or write a ble sniffer firmware, with the modification that it at a given moment sends a packet on the connection it is currently listening to. But note that the signal strength must be stronger than the original device's signal so it doesn't interfere.
The only open source project I'm aware of is Ubertooth. You will also be able to do this with an nRF52 but then you need to write your own sniffer firmware since Nordic Semiconductor's is closed source.
I can't comment on Emils reply yet, < 50 rep:
Nordic Semis nRF Sniffer v2 needs only the nRF52DK and wireshark to work as a general BLE sniffer. At 40$ it's not that expensive. I know for a fact they will release a new dongle soon that will sell for ~10-15 bucks if you can wait a a month or two.
I am developing a logic core to perform data transfer between a FPGA and a PC over ethernet, using a LAN8710 PHY on my FPGA board.
I've achieved to transfer some UDP data packets from the FPGA to the PC. It's a simple core that complies with the PHY transfer requirements. It builds the UDP package and transfer it to the PC.
To check the reception on the PC, I am using Wireshark and as said above, I receive the packets correctly. I've checked the reception with a simple UDP receiver written by myself.
But, I've noticed that I only receive these packets when Wireshark is running on the PC. I mean, if Wireshark is ON, my application receives the packets too, and the counter of received packets of the following picture increases. (This picture is not mine, just one from the internet)
http://i.stack.imgur.com/wsChT.gif
If I close Wireshark, the PC stops receiving packets and the counter of received packets stops. My application stops receiving too.
Although novice on networking topics, I suspect that this issue is related to PC-side. Seems like Wireshark is "opening/closing" the ethernet communication channel, or something like that. Does anyone knows about this issue?
To build a functional core to transfer data between a PC and the FPGA, I've developed a core to transfer and receive UDP packets. Next step will be ARP implementation (to let the PC identify my FPGA board, as I understand). What protocols are necessary to perform full-duplex data transfer between this 2 devices?
Thank you very much in advance,
migue.
Check whether you are able to get appropriate receive interrupt at ethernet driver level on PC-side for a single transmitted packet by FPGA. If you do not get the receive interrupt, check on the transmit side(FPGA) for appropriate transmit interrupts for packet that is being transmitted. This should mostly help you in cornering the issue.
As far as i know, wireshark is just a packet analyzer/sniffer. However, if wireshark is suspected, one option could be to try with alternate packet sniffer to rule out if any such scenario is happening.
A handy tool for determining problems in network and also for determining the network statistics shall be netstat. netstat -sp udp shall list down the statistics only for UDP. There are many other parameters that can be used with netstat for diagnosis.
After many months I solved it, I post to help someone stucked in the same point.
Finally I figured out that Wireshark uses a tool to access the network link layer of the computer. This tool allows Wireshark to sniff all incoming and outgoing packets at a specified network device. To do this, the first step is to OPEN the network device, and that's why my program only worked if Wireshark was open.
Regards.
I have 16 Arduinos that are in very tight spaces and hard to get to when I need to reprogram them with my FTDI cable. I would like to have or create some sort of centralized place where I can connect my FTDI cable, make some sort of selection (switch of some sort), which will then connect the pins my cable is on to the selected arduino.
Does anyone have any thoughts on how this can be accomplished? I've toyed with transistors, but that takes a lot of them and didn't quite work.
Are there any premade solutions that are out there that I have yet to find?
Thanks very much!
Here is a thought! TCP to Serial.
Sound complicated.
Not really.
Note from AVRDUDE's manual the following
For programmers that attach to a serial port using some kind of higher
level protocol (as opposed to bit-bang style programmers), port can be
specified as net:host:port. In this case, instead of trying to open a
local device, a TCP network connection to (TCP) port on host is
established. The remote endpoint is assumed to be a terminal or
console server that connects the network stream to a local serial port
where the actual programmer has been attached to. The port is assumed
to be properly configured, for example using a transparent 8-bit data
connection without parity at 115200 Baud for a STK500.
With this, One could place your Arduino's behind your choice of TCP to Serial Server. Which is available in several forms. Cisco has a gang TS (but that is expensive, unless used). lantronix (and others have single end point devices. But then for Linux, there is "Net2Ser" which can serve up all your ttyS (aka Serial/COM ports).
With the later you could use a raspberry or TP-Link TL-WR703N (
In the latest IDE 1.5.6r2 add one entry for each TCP-to-Serial Port to ./Arduino/hardware/arduino/avr/programmers.txt file. While replacing the IP and Port with corresponding values.
TCP2001.name=TCP 2001
TCP2001.communication=serial
TCP2001.protocol=stk500v1
TCP2001.program.protocol=stk500v1
TCP2001.program.tool=avrdude
TCP2001.program.extra_params=-Pnet:192.168.1.100:2001
TCP2002.name=TCP 2002
TCP2002.communication=serial
TCP2002.protocol=stk500v1
TCP2002.program.protocol=stk500v1
TCP2002.program.tool=avrdude
TCP2002.program.extra_params=-Pnet:192.168.1.100:2002
...
Additionally change "protocol" to "upload.protocol" the following line in ./Arduino/hardware/arduino/avr/platform.txt
tools.avrdude.program.pattern="{cmd.path}" "-C{config.path}" {program.verbose} -p{build.mcu} -c{protocol} {program.extra_params} "-Uflash:w:{build.path}/{build.project_name}.hex:i"
to
tools.avrdude.program.pattern="{cmd.path}" "-C{config.path}" {program.verbose} -p{build.mcu} -c{upload.protocol} {program.extra_params} "-Uflash:w:{build.path}/{build.project_name}.hex:i"
With this you can use "Upload Using Programmer" with the selected programmer to send over TCP, rather then use the Upload.
That all said, it will only work on Linux.
avrdude: ser_open(): network connects are currently notimplemented for Win32 environments
I have a simple xbee network operating where there are a bunch of slaves operating remotely and all talking to one master, who is connected to the server computer. That works no problem.
The slaves all send their ID as part of the packet and I'd like to have the master deliberately send an Ack after a delay. I'm trying to figure out how to do this efficiently and it seems that the only plausible way that doesn't involve reprogramming the master before each Ack is to send the Ack to all slaves and have them ignore the packet if it's not meant for them.
That solution is ok - I just can't figure out the command to use to do this. Is there some sort of Serial sendAll command? All of the devices are on the same ATID.
Typically in this situation, you would configure the master in API mode so you would get "Receive Explicit" frames with source addressing information, and could send with the "Transmit Explicit" frame type, and include addressing information in your frames.
If you use AT mode (transparent serial mode), then you're stuck having to change the DH and DL parameters on your coordinator every time you want to change who you send to. You should avoid using broadcast packets, since each one results in lots of network traffic (IIRC, each router will send the broadcast packet three times).
I do not know of a good XBee library on the Arduino, but it might be possible to port Digi's Open Source ANSI C XBee Host Library to that platform.