The Google H1 Fritz Chip.

Edit: Step-by-step replication instructions for the skeptical experimenter.

This article is a review of what I have been able to discover regarding the Google H1, aka Cr50, aka the “G Chip”, found in all Chromebooks of recent manufacture, including the Asus C101PA, my current candidate for a full delousing attempt.
To my knowledge, there has been no [...]

The secret of the “Debug Accessory Mode” Adapter.

The exact internals of Google’s proprietary “Suzy-Q” debugging device are, at the time of this writing, unknown.
However, I have found how to make an apparently-compatible device:

We connect the USB-C “business end” into a Asus C101PA machine; the USB-B end into a reasonable Linux PC, where we then:

echo 18d1 5014 > /sys/bus/usb-serial/drivers/generic/new_id

…and /dev/ttyUSB0 … 5 , [...]

Posted in: Cold Air, Hardware, NonLoper, SoftwareSucks by Stanislav No Comments

Open Problem: “Debug Accessory Mode” on the Asus C101PA

Edit #2: Aaaand it’s solved:

echo 18d1 5014 > /sys/bus/usb-serial/drivers/generic/new_id

triggers creation of /dev/ttyUSB0 … 5 , several of which spew console log…
Example spew on boot. (Looks like RK’s UART..?)

Edit: apparently they’re USB lines! When connected as D-/D+ through a USB B-connector, to a Linux box, we get a device that enumerates with this descriptor.

The Asus C101PA [...]

Open Problem: Forcing MaskROM Mode on the Asus C101PA

The Asus C101PA is based on a Rockchip RK3399. These have a “maskrom mode”, where if the SPI EEPROM is disabled, the chip will attempt to boot from other devices: first, NAND flash, then microSD, and then finally a USB debug mode where you can attach a A-A cable and use the rkflashtool utility to [...]