SPI flash programming on board.

SPI -Serial Peripheral Interface ISP- In System Programming When power the flash with 3.3v use a good power source. Do not use usb-TTL as your 3.3v power source. A DIY power source is shown to provide 3.3v and 460mA current. ... https://www.youtube.com/watch?v=GzXhWTfYMpk