Making ADB Persistent on Moxee K779HSDL

By default, enabling ADB via /sbin/usb/compositions/902D n is volatile and resets on reboot. Here’s how to make it stick.

Prerequisites

• Moxee K779HSDL with ADB currently enabled
• Or: telnet shell via ./installer util orbic-shell --admin-password 'PASSWORD'

One-liner

adb shell "echo 9 > /usrdata/mode.cfg"

That’s it. Reboot to verify: adb reboot, wait ~30 seconds, then adb devices.

What this does

The Moxee’s boot USB composition script (/sbin/usb/compositions/PRJ_SLT779_9025) reads /usrdata/mode.cfg to select the USB mode. The default value is 3 (RNDIS only, product ID 0xF626).

Setting it to 9 gives:

• RNDIS (USB network)
• DIAG (Qualcomm diagnostic interface)
• Serial (AT commands)
• ADB

Product ID changes from 0xF626 to 0xF622. ADB runs as root.

/usrdata is a persistent read-write partition, so this survives reboots.

To revert

adb shell "echo 3 > /usrdata/mode.cfg"
adb reboot

Notes

• If the device boots from USB power only (poweronreason=USB), the boot script disables USB entirely regardless of mode.cfg. This is normal – just power cycle the device off USB.
• There is also a /usrdata/mode_tmp.cfg that takes priority over mode.cfg but is deleted after one boot. Useful for one-shot mode changes.