RTL8306SD/RTL8306SDM
Datasheet
7.1.1.3
Port4 (5th Port) and Port5 (6th MAC) Status Configuration
The RTL8306SD/RTL8306SDM supports flexible methods to configure Port4 (5th Port) and
MAC5 (6th MAC) NWAY/Force mode, 10Mbps/100Mbps, Full/Half duplex, and Enable/Disable Flow
control.
• When MAC4 (5th MAC) is in MAC mode MII, PHY mode MII, or RMII mode, these operating
abilities can be configured by strapping pins (P4ANEG, P4SPD, P4DUP, and P4FLCTRL) upon reset
according to application.
• When MAC5 (6th MAC) is needed in system applications, the operating abilities should be
configured by writing the register after setting the correct DUALMII/RMII operating mode.
• When MAC5 is enabled, the default status is: Not linked, 100Mbps, Full duplex, flow control enabled.
7.1.2.
Port0, 1, 2, 3 Status Configuration
The 4 ports are separated into 2 groups (GroupX/GroupY) for flexible port configuration using strapping
pins upon reset. The SetGroup pin is used to select the port numbers for GroupX and GroupY.
• SetGroup=1: GroupX = Port0; GroupY = Ports 1, 2, and 3.
• SetGroup=0: GroupX = Ports 0 and 1; GroupY = Ports 2 and 3).
Each group has four pins for selecting initial port status upon reset (ANEG/Force, 100/10, Full/Half,
Enable/Disable Flow Control). Upon reset, in addition to using strapping pins, the
RTL8306SD/RTL8306SDM can be configured via an EEPROM, or read/write operation by a CPU via
the MDC/MDIO interface.
7.1.3.
Flow Control
The RTL8306SD/RTL8306SDM supports IEEE 802.3x full duplex flow control, force mode full duplex
flow control, and optional half duplex back pressure.
7.1.3.1
IEEE 802.3x Full Duplex Flow Control
For UTP with auto-negotiation ability (GxANeg/GyANeg/P4Aneg set to 1), the pause ability (Reg.4.10)
of full duplex flow control is enabled by pins GxEnFC/GyEnFC/P4EnFC on a group basis upon reset, or
internal registers via SMI on a per-port basis after reset. For UTP with auto-negotiation ability,
IEEE 802.3x flow control’s ability is auto-negotiated between the remote device and the
RTL8306SD/RTL8306SDM. If the auto-negotiation result of the IEEE 802.3x pause ability is ‘Enabled’
(Reg.4.10: 1 and Reg.5.10: 1), the full duplex 802.3x flow control function is enabled. Otherwise, the full
duplex IEEE 802.3x flow control function is disabled.
6-Port 10/100Mbps Single-Chip Dual MII/RMII Switch Controller
35
Track ID: JATR-1076-21 Rev. 1.1
REALTEK [ Realtek Semiconductor Corp. ]
