Windows Loader 4.9.7 - Activate Win 7, Server, Vista, XP.zip
Marion Loyd
Each time that I try to upload any code. I have tried three different windows cpus and three different serial cables. Doesn't seem to help. I have looked around the forum for answers, but nothing... The weird thing is in the drop down menu Tools --> Port I can see the "COM" show up when the arduino is connected, but it doesn't say "Com X Arduino Uno" like most of my other boards do. What can I try?
You can use it as an "Arduino as ISP" programmer to do a "Burn Bootloader" operation on the non-working boards. This might possibly put them into a condition where you can upload to them. If you would like to give it a try, you can follow this tutorial:
It doesn't make any sense. It just uploaded a fairly complex code (no idea why) but now it won't upload again. It is almost like the first time you connect it to a "new" usb port and select it in the tools port drop down menu it will upload and then it won't upload any more....
Hello, I have seen the same behavior on several recent batches of Nano Clones as well
Uploads once, never again
Have been using similar clones for years without issue, The old ones used CH340G driver and "old" bootloader. The new ones use "new" bootloader, but only work once. Occasionally I have had them upload a second time after connecting/disconnecting multiple times but no rhyme or reason to it.
Normally you need to do a hardware reset of the microcontroller to activate the bootloader, then start an upload before the bootloader times out and starts the user application. However, after burning bootloader the bootloader is perpetually activated so no reset is necessary, meaning the first upload will work with or without a reset. The board may be in that perpetual bootloader state when shipped by the manufacturer. I haven't actually seen this reported before for a manufactured board with built-in USB adapter chip (it has always been DIY circuits or Pro Minis), but it's certainly possible the manufacturer messed up the reset circuit.
The auto reset circuit (for an example, see these "minimal setup" schematics) is the DTR pin of the USB-TTL serial chip connected to the reset pin of the ATmega2560 via a 0.1 uF capacitor. In combination with the pullup resistor on that pin, it generates a reset pulse when the serial connection is opened.
To test this, you could see whether uploads work after a manual reset. The tricky thing is that when you press the "Upload" button in the Arduino IDE, it first compiles your sketch before starting the actual upload. If you reset the microcontroller immediately after pushing the button, the bootloader will have timed out by the time the upload actually starts. The way to get the timing right is:
While that did not work, you got me thinking. I have a MAX485 chip connected to the hardware serial port and when I popped out that socketed chip it uploaded fine. Earlier i had programed the Nano before i connected it to the rest of the circuit.
Thank You for the quick response
The one that I got to work is still hit or miss with uploading. Sometimes it does fine... other times I get errors. I haven't had a chance, but I will try the suggested solution above and report back if it works for mine. Thanks @in0
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