RTL8211C & RTL8211CL
Datasheet
MDC
z
z
MDIO(MAC)
z
z
0 0 0 0 0 0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
Write
(OP
Code)
PHY Address
0x01
Reg. Address
0x00 (BMCR)
Turn
Around
Reg. Data
0x1340
Idle
Start
Idle
Figure 5. Typical MDC/MDIO Write Timing
6.6. Auto-Negotiation
Auto-Negotiation is a mechanism to determine the fastest connection between two link partners. For copper
media applications, it was introduced in IEEE 802.3u for Ethernet and Fast Ethernet, and then in
IEEE 802.3ab to address extended functions for Gigabit Ethernet. It performs the following:
• Auto-Negotiation Priority Resolution
• Auto-Negotiation Master/Slave Resolution
• Auto-Negotiation PAUSE/ASYMMETRIC PAUSE Resolution
• Crossover Detection & Auto-Correction Resolution
Upon de-assertion of a hardware reset, the RTL8211C(L) can be configured to have auto-negotiation
enabled, or be forced to operate in 10Base-T, 100Base-TX, or 1000Base-T mode via the CONFIG pins (see
section 6.3 Hardware Configuration, page 10). If the RTL8211C(L) is configured to operate only in
1000Base-T mode, then auto-negotiation is still enabled with only 1000Base-T mode advertised.
The auto-negotiation process is initiated automatically upon any of the following:
• Power-up
• Hardware reset
• Software reset (register 0.15)
• Restart auto-negotiation (register 0.9)
• Transition from power down to power up (register 0.11)
• Entering the link fail state
Integrated 10/100/1000 Gigabit Ethernet Transceiver
13
Track ID: JATR-1076-21 Rev. 1.3
ETC [ ETC ]
