Intel PCI User Manual

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284
Software Developer’s Manual
Register Descriptions
Table 13-59. RXCW Register Bit Description
Field
Bit(s)
Initial 
Value
Description
RxConfigWord
15:0
X
Data received during Auto-Negotiation process.
When performing hardware Auto-Negotiation 
(TXCW.ANE = 1b), the “AN link partner ability base page 
register” is recorded in the RxConfigWord.
When TXCW.ANE is clear, then this register is used by 
software to perform software based Auto-Negotiation. In 
that capacity, RxConfigWord records the raw values 
returned from the Auto-Negotiation process.
Reserved
25:16
0b
Reserved
Reads as 0b.
Should be written with 0b for future compatibility.
RxConfigNoCarrier
26
0b
Carrier Sense Indication
0b = Ethernet controller not receiving idle characters 
(Carrier sense is true)
1b = Ethernet controller receiving idle characters (Carrier 
sense is false)
Hardware sets RxConfigNoCarrier when it is receiving idle 
characters (and when receiving link configuration 
information or port status).
Software can use this bit to determine that idles have been 
seen prior to exiting the link start-up procedure.
82544GC/EI only:
Valid only in software Auto-Negotiation mode 
(TXCW.ANE = 0b).
RxConfigInvalid
27
0b
Invalid Symbol during configuration process
0b = Have not received an invalid symbol during Auto-
Negotiation process.
1b = Have received an invalid symbol during Auto-
Negotiation process (bit is LH).
If the Ethernet controller detects an invalid symbol at any 
time, it sets the RxConfigInvalid bit. The bit is latched high 
until read by software. Software is expected to restart the 
configuration process when the Ethernet controller receives 
an invalid symbol at any time during the Auto-Negotiation 
process.
82544GC/EI only:
Valid only in software Auto-Negotiation mode 
(TXCW.ANE = 0b).
RxConfigChange
28
0b
Change to the RxConfigWord indication
0b = RxConfigWord has changed since last read.
1b = RxConfig is unchanged since last read (LH)
Indicates that the Ethernet controller interface has seen a 
change to the RxConfigWord. This bit is latched high until 
read by software.
82544GC/EI only:
Valid only in software Auto-Negotiation mode 
(TXCW.ANE = 0b).