Title: Message
I was researching componants on an older ABo and noticed that the pins on the Media Access Controller that control speed, duplex and negotiation were all unconnected. When these three pins (11, 40 and 42) are low the MAC is forced in to 10Mb mode half duplex and auto-negotiation advertisement is turned off. I would think that ANEG (pin 40) should be tied high so that the  device pluged in to it would not have to rely on a fall back feature to guess at the speed? Should pins 11 an 42 be tied low instead of being left open? I assume that being left open allows them to be influenced by RF and IF noise as well as static to the point where the MAC can't decide if they are HI or LOW or thinks they are hi due to the HIGH-Z state they are in. I am of the opinion that some of the ethernet related issues are causes by this HIGH-Z state.

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