Supermicro H8DGi-F LED (JF1) LED Wiring?

dglatting

Honorable
Jul 20, 2012
5
0
10,510
The H8DGi-F MB had a front panel connector pin out show below. I can find no electrical specifications about the LEDs, such as: is the cathode switched to ground by the pin on the connector and the anode connected to, well, what?

Can someone point me to a clue how to wire this MB to a set of LEDs?


Figure 2-3. JF1: Front Control Panel Header (JF1)

20 19
Ground No Connection
Key Key
Power LED 3.3V
HDD LED FP UID Switch/3.3VSB
NIC1 (Link) LED NIC1 (Activity) LED
NIC2 (Link) LED NIC2 (Activity) LED
OH/Fan Fail/PWR Fail/UID LED Blue_LED_Cathode (UID)/5V SB
Power Fail LED 3.3V
Ground Reset Button
Ground Power Button
 
This got reformatted somewhere. Hope this is cleaner


Figure 2-3. JF1: Front Control Panel Header (JF1)

20 -- 19
Ground -- No Connection
Key -- Key
Power LED -- 3.3V
HDD LED -- FP UID Switch/3.3VSB
NIC1 (Link) LED -- NIC1 (Activity) LED
NIC2 (Link) LED -- NIC2 (Activity) LED
OH/Fan Fail/PWR Fail/UID LED -- Blue_LED_Cathode (UID)/5V SB
Power Fail LED -- 3.3V
Ground -- Reset Button
Ground -- Power Button[/quotemsg]
 


Lets see if I understand this correctly, I should wire the cathodes to ground -- together, and the anode goes to the LED connection (e.g., "NIC1 (Activity) LED")?

TIA
 
I would be wary of using the ground for the led cathod especially for the hdd and power/standby leds as they sometimes switch the ground wires for signalling instead of the positive wires, in some rare cases some motherboards use a floating ground setup for the leds which if connected incorrectly can cause damage to the board and/or leds.
As for getting the anode and cathode mixed up on the leds nothing bad will happen.
 
I was able to find a cable from Supermicro that brought JF1 to individual LEDs and switches. It would have been helpful if Supermicro described the connections, not necessarily in electrical terms though that would have been useful, in terms of Anode here, Cathode there.

I still have questions about the connector because it looks like Ethernet has link /active/ (i.e., something is connected) and link /activity/ LEDs but the cable bridges them; meaning the LEDs are normally on but flash off to show activity.