Port missing on Windows 7

pauloscheidegger · July 22, 2020, 8:16pm

Hi folks,

After some years away from Arduinos I decided to get back. Last time I was using a Windows XP laptop but now I have a Win 7 one, and it seems I've forgotten how to connect the board.

I had done a lot of things following many forum suggestions but didn't got luck (I'm rather outdated at 68...) and hope to find some help here.

When I open Tools the Port option is disabled no matter whether Nano 328 board is connected or not. Device Manager (COM & LPT) shows just un Unknown Device in both cases.

As additional info, as soon as I connect the board, green power on Led shines. red LED labeled "L" flashes briefly, about half second later red LED "TX" also blinks once and it stays with only green LED on.

Message displayed is:

Arduino: 1.8.13 (Windows 7), Board: "Arduino Nano, ATmega328P"

Sketch uses 924 bytes (3%) of program storage space. Maximum is 30720 bytes.

Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.

avrdude: ser_open(): can't open device "\.\COM5": The system cannot find the file specified.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

If I plug my cellphone in that very same USB port, Device Manager stay the same, but Tools>Port is enabled to "COM5". Of course this is of no value to upload any sketch, but it may help you to diagnose my problem.

I tried to update the driver on Device Manager with those under Program Files (x86)>Arduino>drivers but it reports unable to install.

What am I doing wrong?

sterretje · July 23, 2020, 5:38am

Unknown device indicates that you need to install the drivers. Clone Nanos often ship with the CH340 TTL-to-USB converter; identify the chip on your board (not the 328P).

If it's the CH340, you can download the driver from the Chinese website and next run the executable (no Nano connected); on success it will tell you something like "successfully pre-installed".

Ballscrewbob · July 23, 2020, 12:44pm

@pauloscheidegger

Other post/duplicate DELETED
Please do NOT cross post / duplicate as it wastes peoples time and efforts to have more than one post for a single topic.

Continued cross posting could result in a time out from the forum.

Could you also take a few moments to Learn How To Use The Forum.
It will help you get the best out of the forum in the future.
Other general help and troubleshooting advice can be found here.

pauloscheidegger · July 23, 2020, 7:23pm

Sorry for duplicated post, my fault. I'll try to learn how to edit previous post.

When I connect the other Arduino I have (UNO clone) it opens another serial port labeled USB-SERIAL CH340 (COM9). This one works as expected, if it only had all its LEDs on board it would be fine, but at least it talks back to the monitor.

Does it mean I already have CH340 driver installed? I asked because I found an old mini A cable wich I used to connect a GPS but it don't uploaded the sketch to Nano at the other port (COM7) either. Somewhere I found a suggestion to download CH340 driver and update the driver of non functioning port to it. Should I need to update the other port too?

I also tried to find a brand new mini A USB cable but it is rather rare today. I only found some that are not OTG. Does this matter?

sterretje · July 24, 2020, 6:10am

You only have to install a driver once. If it works for your clone Uno with CH340, it should also work for a Nano with the CH340.

In your posts, your throwing COM ports around like there is no tomorrow On the other hand, you stated that the tools->port is greyed out so how could you possibly change from COM5 to COM7? I'm confused.

but it don't uploaded the sketch to Nano at the other port (COM7) either

Please be accurate and provide the details. So you managed to change the COM port? What is the error that you get (the same or different); post it here.

Lastly, for Nanos you have the option to select different processors; once your connection is sorted, try the options under tools->processor (you probably need the old boot loader option).

pauloscheidegger · July 24, 2020, 5:09pm

Thank you much for your help, sterretje!

Your reply left me still more confused since I did though it should have worked for both boards.

My Windows 7 laptop has two USB ports, one on right side and one at back panel. Depending on the port I plug each board it shows a different COMM port on Device Manager as shown below:
Nano on side USB: Prolific USB-to-Serial Comm Port (COM10)
Nano on back USB: Prolific USB-to-Serial Comm Port (COM7)
UNO on side USB: USB-SERIAL CH340 (COM9)
UNO on back USB: USB-SERIAL CH340 (COM3)
In each condition IDE Tools>Port show corresponding COM as above.

The only cable I have with a mini-A connector for the Nano is one that came with an old GPS device I used to plug to my laptop. It has a circuit in the middle and I'm afraid this may be the culprit. It pops the Prolific Comm Port even without Nano attached to the other end.
I also have an USB to mini-A adapter which I tried with Nano board in both USB ports, but IDE Tools>Port stay grayed out and nothing appears at Device Manager. Does the cable needs to be OTG type? If so, could I just jump pin 4 to ground at the Nano board? (I wasn't able to find a suitable OTG cable with mini-A connector).

COM5 only appears at IDE if I connect my cellphone to whatever USB port. Device Manager doesn't show this COM5 but there is always an Unknown device showing there. Hope this clarifies the multiple COMs issue.

It's worth to notice that UNO board appears to work ok. It has a red power LED instead of a green one and it lacks all other 3 LEDS, but at least it is communicating with Serial Monitor. I'll focus on Nano board because it is the only one that fits my proto board and besides it has all 4 LEDs as expected.

Regarding inability to upload sketches to Nano, IDE compiles them, stays for quite a while trying to upload and show this message (verbose upload only since it compiled ok), follows both processor options:

---standard bootloader---
Arduino: 1.8.13 (Windows 7), Board: "Arduino Nano, ATmega328P"

Sketch uses 924 bytes (3%) of program storage space. Maximum is 30720 bytes.

Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.

C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude -CC:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf -v -patmega328p -carduino -PCOM7 -b115200 -D -Uflash:w:C:\Users\PAULO\AppData\Local\Temp\arduino_build_482589/Blink.ino.hex:i

avrdude: Version 6.3-20190619

System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"

Using Port : COM7

Using Programmer : arduino

Overriding Baud Rate : 115200

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x90

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x90

avrdude done. Thank you.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

---old bootloader---
Arduino: 1.8.13 (Windows 7), Board: "Arduino Nano, ATmega328P (Old Bootloader)"

Sketch uses 924 bytes (3%) of program storage space. Maximum is 30720 bytes.

Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.

C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude -CC:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf -v -patmega328p -carduino -PCOM7 -b57600 -D -Uflash:w:C:\Users\PAULO\AppData\Local\Temp\arduino_build_482589/Blink.ino.hex:i

avrdude: Version 6.3-20190619

System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"

Using Port : COM7

Using Programmer : arduino

Overriding Baud Rate : 57600

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xe8

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xe8

avrdude done. Thank you.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

Well, I think this is all I've tried. I hope to have included everything, but please let me know if there is any other info I can provide.
Once again, thank you very much for your help and patience.

pauloscheidegger · July 24, 2020, 5:22pm

Just a correction to my previous post: I misunderstood Nano connector type, it is mini-B not mini-A as I posted.

OTG mini-B cable is difficult to find here.

Sorry by my confusion.

sterretje · July 25, 2020, 1:25pm

Based on the avrdude output, the ports now show in the IDE.

Nano on side USB: Prolific USB-to-Serial Comm Port (COM10)
Nano on back USB: Prolific USB-to-Serial Comm Port (COM7)
UNO on side USB: USB-SERIAL CH340 (COM9)
UNO on back USB: USB-SERIAL CH340 (COM3)

OK, so the Nano uses a Prolific USB-to-TTL adapter. If there is no yellow triangle around it, I think that it's also correctly recognised and driver installed.

Your Nano might have a 168P instead of a 328P; did you try the 168P option?

I found one article and one video about a driver problem, but it was for Windows 10, not Windows 7; just in case, google for prolific usb to ttl

I'm basically out of options after that. You can try to do a search for the VID/PID in combination with the Windows7 keyword; it might show up some known issues.

pauloscheidegger · July 25, 2020, 3:53pm

Thanks for your reply, I'll try the options you suggested and report back.

Regarding the USB-miniB cable, does it need to be OTG or standard is ok?

sterretje · July 25, 2020, 4:03pm

I use standard cables.

Ballscrewbob · July 25, 2020, 6:09pm

That would be both POWER and DATA STANDARD USB cables as OTG cables are variation on USB that depends on the device you are connecting to, to support OTG protocols.

pauloscheidegger · August 4, 2020, 6:48pm

I found the problem: my Nano board was bad. I got a new one and this works exactly as expected!

Thank you all for your help!

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Port missing on Windows 7

Message displayed is:

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions. This report would have more information with "Show verbose output during compilation" option enabled in File -> Preferences.

Related topics

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.