Cant find serial port for arduino / Blynk

Good day everyone, I have built an arduino sketch with blynk an a UNO configured for serial connection and it works fine on my computer. I sent a copy to a friend in Malaysia and, after selecting the right server (thank you again Pete) the sketch works fine. I have now delivered an identical copy to a friend in UK. He is running Windows 10 but unfortunately after plugging the arduino into a USB port of his laptop, the device does not appear under Ports (COM & LPT). Interestingly “USB2.0-Serial” appears under “other devices” and this disappears when the arduino is disconnected. Under Ports (COM & LPT) there is just "Multiport Communications Port (COM3)
When I connect an identical sketch into my computer under Ports (COM & LPT) I have USB - SERIAL CH340 (COM9) which is my arduino UNO (copy)
I have connected another copy of this sketch on UNO to my laptop and it appears (with the port number) fine under Ports (COM & LPT).
Thinking about this this is probably a Windows problem but I was hoping that someone here might suggest what we could try to see the device under the ports field. We have tried going to device manager then view then hidden devices but that dosen’t help. Has anyone else had this problem and if so can anyone please suggest what we could do to try and get the port number for the project so we can edit and run the script. My friend has tried connecting this to a different laptop and has the same issue.

Your friend needs to install a driver so that his PC recognises the CH340 TTL to USB chip and creates the virtual port when the Uno is plugged-in.


Good morning Pete, Thanks for your guidance once again. We have followed the appropriate application note on the site and now see the device as port 4 under Ports (COM & LPT), which we are delighted about !. The .bat file has been amended to reflect that the device is plugged into port 4 but, unfortunately when we plug the UNO into the computer using the serial port and run the script we get the following error:
…lectern files\com2tcptcp.exe" ’ is not recognized as an internal or external command, operable programme or batch file.
Reconnection in 3 s…
Do you recognise this error message, can you suggest what might be causing this error ?
With best regards, Charlie

Well, as I explained in this post…

the com2tcp.exe file is created, if it doesn’t already exist, by re-naming the com2tcp.bin file. For this to work, the com2tcp.bin file needs to exist in the same folder as the script batch file that is being executed.
In addition, the user executing the batch file needs to have permissions to create executables in that folder, which may require the batch file to be ‘run as administrator’ by right-clicking on it.

BTW, why are you still using this horrible serial batch file method rather than a NodeMCU with wifi manager?


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Good day again. I now have 2 more friends to who I have supplied identical devices containing Arduino UNO clones and the same sketch and they both have the same problem. They are both running Windows 10 and have tried to install the VCP driver as described in the Application note AN 396 from the site. They have both tried selecting the “setup executable” link and it says that the files are installed but the device isnt shown under Ports (COM & LPT). They have tried downloading the files, extracting the files then, from the device manager, going to the device that is shown in “other devices”, right clicking then select file to update etc and it wont install. Are we trying to install the right drivers here ?.
Pete, believe me I wish I had had an extra week or so to get the node MCU option working. My problem was that I was so far down the line with these 8 copies of this device that it was too late to turn back. I have got some 12E nde MCU examples and a breakout board together with some 5v to 3.3v converters to work on after this weekend. This serial option is proving frustrating !

I don’t think so.

I doubt very much if these are required. I’ve only had one situation that needed them and that was when using an RFID reader.
What is it that your project does, and what peripherals are you using with it?


[quote=“PeteKnight, post:2, topic:49740”]
driver so that his PC recognises the CH340 TTL to USB chip and creates the virtual port when the Uno is plugged-in
[/quote]. Hi Pete … do you know where we can find this driver please ? Cher’s