I have try update with Core firmware (bundled in particle cli) after a unsuccessful flash on build.particle.io . My Core can only connect to computer via DFU mode, but the LED’s turn off after exiting DFU mode. Computer cannot detect Core USB . I have tried github spark11 version and deep update …

Particle Core's led go blank or breathing white after Update firmware

KennyL May 20, 2015, 12:49pm 8

Ok, it works with following combination.

spark_9 core_firmware + ./particle flash --usb tinker.