88E1111 Datasheet, PDF (61/252 Pages) List of Unclassifed Manufacturers – Integrated 10/100/1000 Ultra Gigabit Ethernet Transceiver

Functional Description
88E1111 Device Modes of Operation
2.3.2 Modes of Operation for Fiber Media
Figure 18 displays the MAC interfaces for fiber modes of operation.
Figure 18: MAC to Fiber Connection
MAC
MAC Interfaces:
- GMII
- RGMII
88E1111
Device
S_IN+/-
S_OUT+/-
SD+/-
Fiber
Transceiver
Fiber Cable
- 1000 BASE-LX
- 1000 BASE-SX
1000BASE-X
Serial
Interface
There are two modes of fiber operation. Table 27 shows the mode to select digital interfaces connecting to fiber
media.
Table 27: Mode Selection for MAC Interfaces for Fiber Media
HWCFG_ MODE[3:0]
0111
0011
Description
GMII to Fiber
RGMII to Fiber
2.3.2.1 GMII to Fiber Mode
The GMII to fiber mode is selected by setting the HWCFG_MODE bits to ’0111’. When GMII is connected to the
MAC and the serial interface is connected to a fiber transceiver, only the 1000 Mbps mode is active.
On the transmit and receive sides, data is converted and sent to and from the serial interface. This mode supports
1000BASE-X Auto-Negotiation.
2.3.2.2 RGMII to Fiber Mode
The RGMII to fiber mode is selected by setting the HWCFG_MODE bits to ’0011’. In RGMII to fiber mode, 1000
Mbps Auto-Negotiation is used.
2.3.3 GMII/MII to SGMII and RGMII to SGMII Mode
The 88E1111 device supports both GMII/MII to SGMII mode and RGMII to SGMII mode. GMII/MII to SGMII mode
is selected by setting the HWCFG_MODE bits to ’1110’, and RGMII to SGMII mode is selected by setting the
HWCFG_MODE bits to ’0110’. The GMII/MII and RGMII to SGMII mode supports all three speeds (10/100/1000).
The SGMII behaves as if it were the SGMII on the MAC side of the interface.
In the case of Auto-Negotiation enable, the SGMII Auto-Negotiation information (speed, duplex and link) received
from the PHY is used to determine the mode of operation. The speed and duplex of GMII/MII and RGMII will be
adjusted accordingly when SGMII Auto-Negotiation is completed. In GMII/MII and RGMII to SGMII modes, link is
defined to be up and the corresponding speed LED will be active when Auto-Negotiation is complete and the PHY
SGMII partner’s link is up. In RGMII to SGMII mode this link up condition will be shown in the in-band status.
In the case of Auto-Negotiation disable, the speed and duplex is determined by Register 20.5:4 for speed and
Register 0_1_8 for duplex. (20.5:4 = 00 selects 10 Mbps, 01 selects 100 Mbps, 10 selects 1000 Mbps.) In GMII/
MII and RGMII to SGMII modes, the link is defined to be up when valid idles are received.
The transmit and receive FIFOs are enabled in both modes. S_CLK± is enabled by default.
Copyright © 2004 Marvell
November 19, 2004, Advance
CONFIDENTIAL
Document Classification: Proprietary Information
Doc. No. MV-S100649-00, Rev. E
Page 61