Take the 2-minute tour ×
Raspberry Pi Stack Exchange is a question and answer site for users and developers of hardware and software for Raspberry Pi. It's 100% free, no registration required.

There are 5 status LEDs on the Raspberry Pi board. While I can guess what the POWER LED signifies (the power being attached), I am not sure about other four.

So, what do OK, FDX, LNK and 10M signify?

share|improve this question
    
Explained here. –  ACarter Jul 1 '12 at 15:48
    
possible duplicate of How do I control the system LEDs using my software? –  Tibor Jul 1 '12 at 17:32
1  
Yes it's duplicate answer - but the question is asked so differently that it's worth keeping. –  Maria Zverina Jul 1 '12 at 20:23
    
No, it is not a duplicate. The linked question asks how to control the LEDs, while this asks what do they mean. Very closely related, but no duplicate. –  That Brazilian Guy Feb 27 at 2:04
add comment

2 Answers

up vote 17 down vote accepted

According to http://elinux.org/RPi_Hardware

Rev. 1.9 Boards

  • D5(Green) - OK - SDCard Access (via GPIO16)
  • D6(Red) - PWR - 3.3 V Power
  • D7(Green) - FDX - Full Duplex (LAN) (Model B)
  • D8(Green) - LNK - Link/Activity (LAN) (Model B)
  • D9(Yellow) - 10M - 10/100Mbit (LAN) (Model B)

Rev.2.0 Boards label the LEDS as

  • ACT
  • PWR
  • FDX
  • LNK
  • 100
share|improve this answer
1  
Update: according to that page, on Rev2.0 boards, the first led is "labelled as 'OK' on Rev1.0 boards and 'ACT' on Rev2.0 boards". –  Blaisorblade Jan 12 '13 at 17:27
add comment

The Raspberry Pi boards have either two or five LEDs on a corner of the board.

They are as follow:

enter image description here

  • ACT (or OK on the older Revision 1 boards): green, blinks on SD card access, off otherwise
  • PWR: red when powered on.

The following LEDs exist only on Model B boards:

  • FDX: green when Full Duplex ethernet is active
  • LNK: green when ethernet is connected, blinks on data transfer
  • 100 (or 10M on on the older Revision 1 boards): orange, indicates 100Mbps ethernet

Sources: adafruit, elinux

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.