3. MaskRom mode

See startup mode for an introduction startup mode

MasRrom mode is the last line of defense against device being bricked. Forced entry MaskRom involved hardware operation, have certain risk, so only in the situation that deivce failed entering the Loader mode, you can try MaskRom mode.

Please read carefully and operate carefully!

The operation steps are as follows:

  1. Disconnect all power supplies.

  2. Connect the device and host PC with Type-C data cable.

  3. Hold down the Maskrom button

  4. Connect DC power

  5. Wait a few seconds, release the button.

_images/maskrom_test_points.jpg

Where is the Maskrom button?Find in the Interface Definition

When the board has NOR flash at the same time, if EMMC is empty and there are burned files in NOR flash, it is necessary to short circuit the D0 and GND test points near NOR flash to enter Maskrom mode. And now we have to refer to the chapter “Switching Upgrade Storage” for upgrade

_images/maskrom_test_points_flash.jpg

At this point, the device should go into MaskRom mode.

_images/maskrom_zh.png