Flashing via a programmer is safer than USB for "dead" boards.
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Plug the USB into the board and power it on. The standby light should blink rapidly, indicating the update is in progress. until the blinking stops. Flashing via a programmer is safer than USB
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USB Programmer. This board usually requires a direct ISP connection or removing the SPI Flash IC (usually an 8-pin chip like the 25Q32 or 25Q64) to flash the software.