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My Arduino board is malfunctioning in its bootloading and I thought weather I can overwrite the previous bootloader on the atmega. I mean to ask than can I simply reinstall bootloader on a chip that already has a bootloader installed.

marked as duplicate by Juraj, sempaiscuba, VE7JRO, Greenonline, jose can u c Mar 27 at 15:54

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  • yes. you need an ISP programmer or other Arduino with "Arduino as ISP" sketch. – Juraj Mar 18 at 14:40

Yes you can. A Programmer that is driven from a PC and connects to SCK/MOSI/MISO/Reset/Power/Gnd (the ICSP header on an Uno/Mega), or a Standalone Programmer that can program a bootload program stored on an SD card and connects to the same ICSP pins, is needed to access the bootload memory to load/reload the bootloader.

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