2 Replies Latest reply on Nov 11, 2009 7:35 AM by RLM

    Is there 82574L LED_ON and LED_OFF errata ?

    Green Belt

      We switched from using the 82573L to the 82574L but the LED_ON LED Mode option doesn't work the same in the 82574L as in the 82573L even though the docs appear to be identical.

      In the 82574L LED_ON doesn't turn on the LED until, say, I set the "invert" bit also.


      I see code changes in the Linux drivers to support the 82574L use the invert trick to turn on the LED. Is there a published errata about this, that I've been unable to find, or has others just had the same observations and implemented a work around ?


      Should I consider the LED_ON not working the same as in the 82573L a set feature of the chip and not expect it to change or should I implement the work around defensively for the the day it works correctly i.e. use the invert bit with the LED_OFF mode ?

        • Re: Is there 82574L LED_ON and LED_OFF errata ?
          Green Belt

          The 82574's blink bit in the LEDCTL register has some challenges when
          there is no link, therefore software needs to manually turn on and
          off the LED using a timer to make it blink to identify the adapter.

          Also the 82574Ls LED_ON mode suffers from the same challenges when there is a lack of link, that's why we needed to add the workaround to properly turn on the LED.  With NO link, the LED Invert bit needs to be set to turn the LED on in the 82574L.


          We are working on documenting this, so please check later in the year for a new revision of the datasheet and/or the spec update depending on where it lands. 


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            • Re: Is there 82574L LED_ON and LED_OFF errata ?
              Green Belt


              Then to confirm my sanity or lack thereof, the 82573L works as currently documented and the 82574L doesn't in regard to blink and LED_ON ?


              I understood from the 82573L & 82574L docs that blink doesn't work when using the "invert" option but I assume you are saying in addition the 82574L even without the invert being set requires a link to operate ?


              So by using the invert to turn on the LED and manually blinking a LED set to the LED_OFF mode the 82573L and 82574L can be handled the same way ?