So, i found this instruction and tried to follow it: https://www.instructables.com/How-to-Restore-the-Arduino-UNO-R3-ATmega16U2-Firmw/
I completed every step, until the last step: burn bootloader
Here the error message:
avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: Expected signature for ATmega16U2 is 1E 94 89
Double check chip, or use -F to override this check.
So yeah i don't know to fix this, please help, i'm very appreciate it, thanks guys
You're not talking to the 16u2, but rather the 328p (the chip you normally program).
Youre on the wrong 6-pin ISP header.
Is there no other 6-pin ISP header? In that case, are you sure it is an uno or faithful clone, as opposed to a "clone" with some other dedicated usb-serial adapter chip? Those cant be reprogrammed like that. (They also arent very prone to problems with the usb serial chip - it's pretty easy to burn out the 16u2 theough electrical abuse, while I dont think I have ever managed to trash a ch340...)
Why do you desire to do this, anyway? What is it doing wrong?
ok so the main reason i do this is because i want to make an adruino auto-play the game for me so that i can avoid all tedious part (like farming). But to do this first i need to put my board into DFU mode, then use Flip to upload hex file to the board. But i can't, after perform the pin reset, in device manager an "Unknown Device" category didn't show up. This is the main problem, at first i thought maybe the reason is because i bought a counterfeit board (my first 2 board is counterfeit, i don't know it), but after i bought an Elegoo uno r3 from official seller on amazon (link: https://www.amazon.com/dp/B01EWOE0UU/ref=nav_timeline_asin?_encoding=UTF8&psc=1), it still didn't solve the problem, so after some research on internet, i deicide to upgrade my board firmware with this file: Arduino-COMBINED-dfu-usbserial-atmega16u2-Uno-Rev3.
Here's how i do it, i use one counterfeit adruino uno r3 i bought before to make it become ISP (it had bootloader because i can upload AdruinoIsp to it), then the target board is an elegoo uno r3, but i didn't wire it like the picture in the first link, instead i wired it like this (picture in attachments).
Before i did this I also tried to upload hex file to my board without enter DFU mode like in this link How to upload HEX files to Arduino Uno - Microcontrollers - Arduino Forum, here is my command: C:\PROGRA~2\Arduino\hardware\tools\avr/bin/avrdude –CC:\PROGRA~2\Arduino\hardware\tools\avr/etc/avrdude.conf-v -patmega328p -carduino -PCOM6 -b115200 -D -Uflash:w: C:\Users\HP\Desktop\2020/DaySkipper.hex:i
But it didn't work, error picture in attachment.
I also tried some software like Xloader. It didn't work too.
Hope you guys can see what i did wrong
As DrAzzy indicated, you're trying to program the 328P and not the TTL-TO-USB chip.
Do you see the little 6 pin header (2x3 pins) next to the reset button on the target board in your image? That is where you need to connect the wires to program the 16U2 (including the reset).
Note that I have never done this exercise, I would rather use a board with native USB that can be used as a HID; think Arduino Leonardo or Micro or SparkFun ProMicro; there are others.
