Software Developer’s Manual 167
Ethernet Interface
Table 8-5. Internal Serdes Mode1 Auto-Negotiation Skipped
TXCW.ANE = 0b

8.6.4 Internal PHY Mode Control Bit Resolution

Tables 8-6, 8-7, 8-8, and 8-9 list how Auto-Negotiation affects control bits in the Ethernet
Controller.
Refer to IEEE 802.3z, clause 37 for information related duplex and flow control link resolution per
the 802.3z Auto-Negotiation method. The Ethernet controller fully complies to the specified
resolution functions.
Table 8-6. GMII/MII Mode – PHY Speed Indication
CTRL.FRCSPD = CTRL.ASDE = CTRL.FRCDPLX = 0b
1. TBI for the 82544GC/EI.
Control Bit Effect on Control Bits
CTRL.FD Duplex is set by software for the desired mode of operation
CTRL.SLU Set by software
CTRL.RFCE Set by software for the desired mode of operation
CTRL.TFCE Set by software for the desired mode of operation
CTRL.SPEED No impact; speed always 1000 Mb/s in Internal SerDesa mode
STATUS.FD Reflects the value of CTRL.FD
STATUS.LU Reflects CTRL.SLU and internal link indication
STATUS.SPEED Internal SerDesa Mode is always 1000 Mb/s; fixed at 10b
a. TBI for the 82544GC/EI.
Control Bit Effect on Control Bits
CTRL.FD Duplex is set per internal signal after link up assertion by PHY.
CTRL.SLU Software should set to allow PHY to control.
CTRL.RFCE Must be set by software after reading flow control resolution from MII
registers.
CTRL.TFCE Must be set by software after reading flow control resolution from MII
registers.
CTRL.SPEED Ignored; no impact on speed.
STATUS.FD Reflects the value of CTRL.FD as above.
STATUS.LU Reflects link status and SLU set.
STATUS.SPEED Speed status bits reflect speed resolved from speed indication inputs from
PHY.