System LED

[stephen fleming]

I am curious about what the purpose of the LED next to the charge LED on the board is. On the pin-out diagram of the expansion connector it is identified as System LED.

[tllim]

I am curious about what the purpose of the LED next to the charge LED on the board is. On the pin-out diagram of the expansion connector it is identified as System LED.

This LED is software programmable, and no dedicate assigned function.

[Andrew2]

I am curious about what the purpose of the LED next to the charge LED on the board is. On the pin-out diagram of the expansion connector it is identified as System LED.

This LED is software programmable, and no dedicate assigned function.

Please consider telling us to which pin it is connected, then using longsleep's minimal Ubuntu image, define it in the .dts file and then put something like 

Code:

(echo heartbeat >/sys/class/leds/green_led/trigger ; sleep 60 ; echo none >/sys/class/leds/green_led/trigger) &

in /etc/rc.local. This way you could provide a small 'DOA-or-not.img' every user can use to see whether the board boots at least or not.

[stephen fleming]

I am curious about what the purpose of the LED next to the charge LED on the board is. On the pin-out diagram of the expansion connector it is identified as System LED.

This LED is software programmable, and no dedicate assigned function.

Please consider telling us to which pin it is connected, then using longsleep's minimal Ubuntu image, define it in the .dts file and then put something like 

Code:

(echo heartbeat >/sys/class/leds/green_led/trigger ; sleep 60 ; echo none >/sys/class/leds/green_led/trigger) &

in /etc/rc.local. This way you could provide a small 'DOA-or-not.img' every user can use to see whether the board boots at least or not.

According to the schematic diagram, the user programmable LED is controlled by PL7 on the A64 CPU.

[longsleep]

Where should this LED be located? I am not seeing it, maybe i am blind. Can you post a picture where it is marked?

Also PL7 is used by s_jtag0@0 in the device tree. Can you provide a link, hint where you see that in the docs?

[Andrew2]

Maybe that's the culprit (leds need to be connected to EXP connector): 

[longsleep]

Mhm ok, but where is the actual LED? Especially "purpose of the LED next to the charge LED on the board" . I can't see it - Please mark eg. in https://www.stdin.xyz/media/arm-board-party-1.jpg

[stephen fleming]

Mhm ok, but where is the actual LED? Especially "purpose of the LED next to the charge LED on the board" . I can't see it - Please mark eg. in https://www.stdin.xyz/media/arm-board-party-1.jpg

                                                                                                                                  ^
                                                                                                      
The LED in question is located right next to the charge LED(marked Chgled) and is just called LED on the board and System LED on the expansion connector pin out sheet.

[longsleep]

                                                                                                                                                                                                               
The LED in question is located right next to the charge LED(marked Chgled) and is just called LED on the board and System LED on the expansion connector pin out sheet.

No LED that i can see. I suppose you mean the (unused) PINs at the very bottom.

[stephen fleming]

                                                                                                                                                                                                               
The LED in question is located right next to the charge LED(marked Chgled) and is just called LED on the board and System LED on the expansion connector pin out sheet.

No LED that i can see. I suppose you mean the (unused) PINs at the very bottom.

Yes, the software programmable and charge LEDs are optional  and are not installed on the board. When my board arrives, I plan on wiring up the LEDs and the power and reset switches.