>Have you tried holding down the power button?
20-25 seconds, when no leds, other than charge, forces complete shutdown
I call it "extra long press" , when you put wrong uSD card in for other SBC
--edit--
for rkdeveloptool, all bootable devices MUST be removed, includes emmc
20-25 seconds, when no leds, other than charge, forces complete shutdown
I call it "extra long press" , when you put wrong uSD card in for other SBC
--edit--
for rkdeveloptool, all bootable devices MUST be removed, includes emmc