Hello,
Although the Segger J-Link OB firmware for the micro:bit v2 works very well for J-link uploads/debugging, the firmware does not handle states of the Power & USB activity LEDs and the Reset/Power Button correctly.
The Power LED, USB Activity LED, and the micro:bit v2 Reset/Power button are connected to the NXP KL27Z USB interface chip.
The J-Link OB firmware should add support for the original functionality of the Power/USB activity LEDs and the Reset/Power Button. It would be greatly appreciated. Thank you.
The tables below detail the differences.
With the original software (OutOfBoxExperience code) on the micro:bit v2 & CMSIS-DAP, the Power off (push & hold power button) causes the Power LED to blink and the USB activity stays ON (if connected to PC USB) and the micro:bit v2 shuts down. If power button is pressed again, micro:bit v2 resets and continues to run the loaded program.
With the original software (OutOfBoxExperience code) on the micro:bit v2 & Segger J-Link OB, the Power off (push & hold power button) causes the Power LED to be OFF and the USB activity stays ON (if connected to PC USB). However, the micro:bit v2 does not shutdown.
In addition, if the micro:bit v2 is connected to a battery, the USB activity LED blinks rapidly. This is quite annoying. Also, in the instance, the Power LED stays off.
Although the Segger J-Link OB firmware for the micro:bit v2 works very well for J-link uploads/debugging, the firmware does not handle states of the Power & USB activity LEDs and the Reset/Power Button correctly.
The Power LED, USB Activity LED, and the micro:bit v2 Reset/Power button are connected to the NXP KL27Z USB interface chip.
The J-Link OB firmware should add support for the original functionality of the Power/USB activity LEDs and the Reset/Power Button. It would be greatly appreciated. Thank you.
The tables below detail the differences.
| NXP KL27Z | micro:bit v2 connected to | Power LED (red) | USB activity LED (orange) |
| CMSIS-DAP | Mac/PC via USB | ON | ON |
| CMSIS-DAP | Power pack via USB | ON | OFF |
| CMSIS-DAP | Battery | ON | OFF |
With the original software (OutOfBoxExperience code) on the micro:bit v2 & CMSIS-DAP, the Power off (push & hold power button) causes the Power LED to blink and the USB activity stays ON (if connected to PC USB) and the micro:bit v2 shuts down. If power button is pressed again, micro:bit v2 resets and continues to run the loaded program.
| NXP KL27Z | micro:bit v2 connected to | Power LED (red) | USB activity LED (orange) |
| Segger J-Link OB | Mac/PC via USB | OFF | ON (initially blinks) |
| Segger J-Link OB | Power pack via USB | OFF | Blinks rapidly |
| Segger J-Link OB | Battery | OFF | Blinks rapidly |
With the original software (OutOfBoxExperience code) on the micro:bit v2 & Segger J-Link OB, the Power off (push & hold power button) causes the Power LED to be OFF and the USB activity stays ON (if connected to PC USB). However, the micro:bit v2 does not shutdown.
In addition, if the micro:bit v2 is connected to a battery, the USB activity LED blinks rapidly. This is quite annoying. Also, in the instance, the Power LED stays off.