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Topic: Nano - Only upload once (Read 172 times) previous topic - next topic


Hi, I have a Nano and have installed the CH340 software and can upload Blink to it.

But, that's the last time I can upload until I reboot the computer with the Nano connected. Then I can upload just once again.

I tried with two other nanos and this does not happen, they upload as many times as I like.

I am reluctant to throw the errant one in the trash as it does upload once every boot, so, I could use it on a project. But, I would like to be able to upload more than once per session if it is possible to fix this issue.




Real Nano has FTDI chip for USB, so you apparently have a clone of some kind.

Check the fuse settings being used, maybe they are incorrect and prevent further uploads.

Or, get a Programmer, and upload via the SPI pins and not the USB interface.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.


CR, thanks, but you obviously think I know much more than I actually do. The first upload works using the CH340 drivers. I have tried using the FTDI drivers instead of the CH340. The FTDI would not install. Win8.1 said "found no suitable drivers." I went back to FTDI and got an older version, same answer.

I have done a lot of searching and tried many things including swapping cables before asking here. Just tried the loop back test and got nothing at all. Used puTTY and Serial Monitor. Typed and nothing came back.

So, fuses? What, where and how?

I will look for instructions for using SPI pins and programmer.


A Nano with a CH340 chip is fine. It may not be the original but the CH340 chipset is perfectly fine.

I don't think it's a Arduino problem but a computer /IDE problem. Which Arduino IDE do you use? Wat is the exact error message?

 If you just disconnect the USB cable after a program, can you upload a sketch again?

Btw, make the upgrade to Windows 10. Whole lot of improvement.
Use fricking code tags!!!!


Sep 23, 2015, 01:04 am Last Edit: Sep 23, 2015, 01:06 am by WaitSome
Hell will be freezing over before I allow msoft to scrape my digital life with win10. Have you really read the Privacy and EULA contents?

OK, thanks for the suggestions, and I think you are correct. It is not an Arduino problem directly as I tried using another PC with win7-pro. Same thing but this time I got an error message that said "Com5 port access is denied."

The error I get with win8.1, is "avrdude: stk500_recv(): programmer is not responding"

It seems that after a reboot, the port is available, but after the first upload, windows is denying further access to that port. The Arduino IDE (1.6.5) is still showing the port as available, so it doesn't know about it, hence the attempt to upload and resultant error.

BUT, having said that, I can use puTTY on that same port and it handles a loop back fine, so it seems it may be something with the way the Arduino is trying to access the port the second time around.

All just guessing, but would really appreciate some help here.


You can just turn off like all the privacy crap ;) It's not the default ofcourse, but you can just turn off a lot of check boxes.

Before programming the IDE does not show if the COM port is availeble or not. It just lists the ports. Which driver have you installed? http://www.wch.cn/download/CH341SER_EXE.html is the link to the driver (v3.4).

So, after programming the Arduino once you can putty to the port and do the loop back test?

And if you unplug and re-plug the Arduino, can you program once again?

And can you try IDE 1.6.4?
Use fricking code tags!!!!


Thanks for the continued help, but the **only** way it will upload is right after a reboot of the PC. Then it is single shot affair again.

But, moving along, I installed the un-signed USBasp programmer drivers and burned the boot loader again. The IDE showed "Burn complete," but still could not upload.

I tried using the USBasp and can upload as often as I like so it looks like something has fried in the Nano. Now that I have the USBasp drivers installed I can just use that when I need to.

It might be worth noting that this Nano was my first one and it has been working fine for several weeks. The two recent Nanos are showing the same version of the CH340-G chip on the underside. So, it looks to be a Nano issue, but at least the USBasp works, so will live with that. I should never expect too much for 7-bucks. :)

Thanks for trying to help.


Mm, yeay, then possibly you fried the CH340 on that board if the other two boards work fine fine and have the same chip.
Use fricking code tags!!!!


This is an interesting thread and the reported problem is bizarre.  I've had a couple CH340G Nanos with cold solder joints and some parts eventually fell off.  I wonder if your board has a problem like that which has not yet revealed itself with a physically apparent problem.  On my boards I touched up the joints with a very pointy conical tip soldering iron while holding the part (resistor, cap, chip, etc.) in place firmly with a toothpick. 



It is a weird issue. It could be a dry joint, I had checked that first off as I had to solder a header to it when it arrived. Knowing it was a 7-buck item, a trip through the reflow oven was almost mandatory. :)

But, I can live with the USBasp approach as IDE 1.6.5 has a key combo for using it, so not that much of an issue. I guess not everyone has a USBasp though. But for 6-bucks even that is not so onerous. Plus, of course, one could use another Arduino as the ISP programmer too.

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