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One solution for AVRDUDE/STK500 and Port Issues (don't know why it worked). - Avrdude, stk500, Bootloader issues - Arduino Forum
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One solution for AVRDUDE/STK500 and Port Issues (don't know why it worked). - Avrdude, stk500, Bootloader issues - Arduino Forum
STK500: A Great Way to Program Microcontrollers
arduino uno - avrdude: stk500_recv(): programmer is not responding + avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x47 - Arduino Stack Exchange