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Altera_Forum
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18 years ago

Configuring triple speed ethernet MAC with National DP83848 PHY in MII interface

Hi I am trying to make a design with a triple speed ethernet MAC from Altera work. I am using a National DP83848 PHY and the small 10/100 version of the MAC. I have attached a snapshot of my sc...
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Altera_Forum
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15 years ago

After contacting support for the board manufacturer and National Semi support, we're returning our board for replacement, suspecting defective DP83865DVH devices.

Board manufacturer support said this was a "known problem" and are reworking boards to resolve. Temporary work around was to force the negotiated speed to 100 Mbps or below. Didn't work for us. One device showed a negotiated speed of 100 Mbps but still didn't work in the tx direction. The other device stayed at 1 Gbps (though it was never connected to anything capable of 1 Gbps) and showed no signs of life. Both devices were very hot to the touch from the first time they were configured.

National Semi support said getting very hot in a few seconds means a faulty DP83865DVH part or possibly a board problem -- should return to board mfgr.

Also, here's a thread on another forum where defective DP83865 devices are discussed:

listsDOTgnuDOTorg/archive/html/discuss-gnuradio/2010-04/msg00603.html