Title: Message
OK, I opened my mouth before I finished my research. I am completly wrong. All three pins are tied to a resistor network effectivly tieing them high. It has been that way from then begining and still is. Oops
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom Haynes
Sent: Friday, August 08, 2003 12:46 AM
To: [EMAIL PROTECTED]
Subject: RE: [smartBridges] MAC fixed at 10M/half no auto negotiate

This was based off of an older (w/ 50' tail) unit using a visual inspection only. If the circuit board is multi-layered then I could be completely wrong. It has already been brought to my attention that the actual circuit diagram of some version of the unit is different than what I noticed.
 
DICTIONARY
ABo = smartBridges airBridge Outdoor
MAC = Media Access Controller, the part that knows how to talk "Ethernet"
duplex = both directions at once
negotiation = a means for two units to decide how to communicate
advertisement = one unit telling anything listening how to communicate with it
ANEG = abbrv. for auto-negotiate
pin = a shiny metal tab sticking out of the squarish hunk of plastic, meant to carry an electrical current
tied high = a signal voltage above ground, in this case 3.3v
tied low = when the pin is grounded
high-z = high impeadance
RF = Radio Frequency
IF = Intermeidate Frequence
issues = problems that are incompletly verbalized or uncommon and look better when called issues
features = bugs that end up actually being usefull
"I am of the opinion" = a long winded way of saying "My guess, 'cause I don't really have a clue"
 
Sorry Folks, I couldn;t help myself :-)
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of phantam
Sent: Friday, August 08, 2003 12:11 AM
To: '[EMAIL PROTECTED]'
Subject: RE: [smartBridges] MAC fixed at 10M/half no auto negotiate

GO TOM! I missed what half of those words meant but hey more power to you, actually in all good sense it does make sense is this in only the older ones or the newer ones as well?

 


From: Tom Haynes [mailto:[EMAIL PROTECTED]
Sent: Thursday, August 07, 2003 2:29 AM
To: Smart Bridges list

 

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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