I have microcontroller pic16f887 and serial ethernet board. When start browser i have problem - the message is this site can't be reached and i can show the content in browser. What may be the problem???? I use HTTPServerExample
http://www.mikroe.com/add-on-boards/communication/serial-ethernet/
Is the IP address configured correct? Wireshark is a very nice tool you can run on your PC to track the TCP/IP traffic and try to detect what goes wrong.
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I am developing embedded microcontroller hardware using a Texas Instruments Starter Kit. I am writing the firmware for the Ethernet link between my microcontroller and x86 Windows desktop.
I have written my own Ethernet driver for the microcontroller and my own protocol driver. So I have absolute FULL control over what data is being transmitted to and from the microcontroller. Up until now, I have managed to write ARP, IP, and ICMP drivers.
I use Wireshark on Windows closely to monitor all data frames going in and out. Now when Wireshark is capturing, "ping" from the console works correctly, but when I stop capturing on Wireshark, my ping fails with "Destination host unreachable." I check the logs on my microcontroller; I see Windows is sending ARP requests, and the microcontroller is replying to them correctly. But the network driver in Windows is filtering them away. So no ICMP requests are being sent. When I check the MAC table using "arp" from the console, my microcontroller is in the list while capturing but not when not capturing its not in the list.
What could be the problem, and how can I debug this problem? Are there any tools/apps for Windows that give statistics on dropped/filtered packets?
I found the problem, there was a punny padding missing in my ICMP echo reply. I did a side by side comparision between a working ping with my wifi router vs my microcontroller on wireshark and found this difference. I thought it wasn't such a big deal, apparently not.
Although what has it got to do with wireshark capturing, I have no clue.
Currently I have a server, that communicates with a projector through a RS232. The server opens a com port when the projector is connected. The same happens to any PC when a certain type of device is connected through the USB (lets say an Arduino for example). What I want to do it basically replace the projector with a PC/Arduino/Raspberry without the server noticing anything. That would mean the server will recognise the connected PC and open a COM port for it. What do I need to do on the PC so that it automatically opens a com port on the server? I guess there is something very basic that any printer, Arduino, projector etc does, that computers recognise it as a "com port device".
P.S. Doesn't matter the OS on the PC, I just need to make it work and then implement w/e I need to do with the established communication over the port.
P.S.2 I've searched a lot about it, but probabl I am doing it wrong, because I didn't find my type of question anywhere.
COM ports are basically hardware that is detected by the system. Let's say, if an Arduino is connected to a PC, it has its onboard USB to TTL converter which can be found in the device manager(if using windows). Similar USB to TTL converters are there in the market like CP2102, PL2303 which acts like a COM port even if no device is connected further to it. it may be possible that the program you are using(as you referred server) may be sending some data over the serial port and verifying the hardware.
What you need to do to replace it is, first of all, find the baud rate at which the communication is going on, then, listen over the serial lines which machine is sending which message in the sequence(there must be a handshake as I mentioned earlier), if a complicated algorithm is not used by the device, you can simply mimic the device by sending same messages over serial.
I bought an ESP12F (esp8266 series). My code a led blinker and works my old ESP12E.
After I uploaded via my COM6 port and started the code on ESP12F then the windows COM6 port disapeared from my device manager :(
The port apeared when I disconnect the USBtoSerial (CH340 based) device from my ESP12F. (The code not relevant able to empty too)
I can't use the ESP12F serial port. :(
What can I do?
Thanks, Gabor
The code not relevant
The COM port works and appear only if the ESP12 GPIO0 connected to GND and after reset.
I found the solution and the main problem. So the esp8266 consume bigger than the USBtoSerial adapter capacity. You need an external 3.3V power source (or battery).
Thanks.
I have gone through several links online but I have not found any appropriate solution to it. I am wondering if there is a way to connect an Arduino with WiFi without using any shield or any other external hardware. My laptop is connected to WiFi and the arduino board is connected to the laptop with an USB cable. I want to access/run the data for the Arduino using WiFi. Is there a way to do it?
Hope my query makes a sense.
Thanks.
Let's restate your question for clarity - you want to share the laptop's Internet connection (e.g. via WiFi) with the Arduino connected to the laptop with a USB cable, with no additional hardware?
Assuming I restated it correctly, the Arduino's USB connection provides a virtual "serial port" for communication. This means you can use an "IP over serial" solution for Internet access. One such common and widely supported solution is PPP.
However, programing the Arduino with IP over PPP stack requires significant amount of memory and is probably an overkill for whatever it is you're trying to do.
You're probably better off designing a custom-tailored protocol for the serial communication between the Arduino and a small gateway program you can program and run on the laptop.
If you're bent on a complex solution that provides full Internet access to the Arduino, the steps to achieve what you're after are:
Program the Arduino with a TCP/IP over PPP protocol stack, running on the serial port. You'll probably need an Arduino MEGA.
Setup the laptop to be a PPP endpoint on the Arduino's serial port. For a Windows machine you can refer to this page for information on how to do that.
Once the PPP link is up, you can setup the laptop's OS to share Internet access to the PPP link.
I've been trying to test a FT201XQ USB-I2C breakout board: UMFT201XB-01, so I can connect it to a master device such as an Arduino and sniff what that device is sending through I2C.
To see the output of the slave device I have successfully configured a Virtual COM PORT by installing the D2XX drivers provided by ftdchip.com. I can open the serial port through puTTY and everything seems fine in that regard.
Then, i've loaded the "master_writer" example on my Arduino, which sends 1 byte at a time to an address (0x22 is specified in the UM201XB-01 datasheet as the default address).
Nothing seems to happen in the COM port that i've earlier opened. Do I need to configure/program the FTDI device in some way? In that case, how can I do it, in a general way?
UMFT201XB-01 board http://www.ftdichip.com/Support/Documents/DataSheets/Modules/DS_UMFT201_220_230XB.pdf
Thank you in advance, and sorry if this is a "noob" question : P