Why do we need to set Tools > Programmers in Arduino IDE?

Can anyone explain the role of Tools > Programmer and why/ when we should select one of the various options given such as: AVR ISP, AVR ISP mkii, USB asp etc. And say if i were using the Virtual COM port 6 to burn a sketch into the arduino board, which one of the options should be set by me?

Thanks in advance.

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Priyankar

IF you have a programmer, you use one of those options. If you're simply uploading via a USB cable, you don't need to worry about it. However, if you've purchased an external programmer, such as the AVR-ISP, an stk500, or even if you're uploading via an ArduinoISP, you'll be selecting one of those options and instead of hitting Upload, you'd hit Upload Using Programmer (look under the File menu).

What setting do you use if you are using an external USB-to-TTL FTDI-type cable or adapter?

mojotexas:
What setting do you use if you are using an external USB-to-TTL FTDI-type cable or adapter?

None of them, as then you are uploading via USB serial method and the bootloader code on the board
handles burning the sketch into the flash memory, when you hit the normal upload sketch command.

Lefty

"None of them" is not an option. One will always be selected. Does this mean the IDE will ignore what is selected when I'm not using an external program?

Currently having some problems with "avrdude: stk_500_getsync(): not in sync: resp=0x00" when I try to program the Arduino.

Am I wasting my time selecting different programmers and trying again?

Nick

The selection is ignored if you are not using an AVR ISP Programmer to burn a bootloader or a sketch via the ICSP header.

The message you see when downloading via the serial port (USB) indicates the chip is not responding.
Try a different cable, try the Loopback Test (see programming forum), confirm the chip has a bootloader installed.

Old thread, I know, but maybe someone out there will benefit.
Check that you have the correct COM port selected.
Tools->Serial Port

Yes, you kind of are wasting your time. I know this is really old, but I was having the same problem and solved it with pretty simple logic. What you should do is unplug the Arduino, then shut down the IDE. Start up the IDE again, then plug in the Arduino. Should work.