RTL8201E(L)
Datasheet
8.1.3. Interrupt (RTL8201EL-VB Only)
Whenever there is a status change on the media that the RTL8201EL-VB detected, the RTL8201EL-VB
will drive the interrupt pin (INTB) low to issue an interrupt event. The MAC senses the status change and
accesses the registers through the MDC/MDIO interface in response.
Once these status registers have been read by MAC through the MDC/MDIO, the INTB is de-asserted.
The RTL8201EL-VB interrupt function removes the need for continuous polling through the
MDC/MDIO management interface.
8.2. Auto-Negotiation and Parallel Detection
The RTL8201E(L) supports IEEE 802.3u clause 28 Auto-negotiation for operation with other transceivers
supporting auto-negotiation. The RTL8201E(L) can auto-detect the link partner’s abilities and determine
the highest speed/duplex configuration possible between the two devices. If the link partner does not
support auto-negotiation, then the RTL8201E(L) will enable half duplex mode and enter parallel
detection mode. The RTL8201E(L) will default to transmitting FLP (Fast Link Pulse) and wait for the
link partner to respond. If the RTL8201E(L) receives a FLP, then the auto-negotiation process will go on.
If it receives NLP (Normal Link Pulse), then the RTL8201E(L) will change to 10Mbps and half duplex
mode. If it receives a 100Mbps IDLE pattern, it will change to 100Mbps and half duplex mode.
8.2.1. Setting the Medium Type and Interface Mode to MAC
Table 24. Setting the Medium Type and Interface Mode to MAC
FXEN
COL/SNI
RXDV
Operation Mode
H
H
H
L
L
L
L
L
H
L
L
H
L
H
X
L
Fiber Mode and MII Mode.
Fiber Mode and RMII Mode.
Fiber Mode and SNI Mode.
UTP Mode and MII Mode.
UTP Mode and RMII Mode.
UTP Mode and SNI Mode.
H
X
8.3. Flow Control Support
The RTL8201E(L) supports flow control indications. The MAC can program the MII register to indicate
to the PHY that flow control is supported. When the MAC supports the Flow Control mechanism, setting
bit 10 of the ANAR register using the MDC/MDIO SNI interface, then the RTL8201E(L) will add the
ability to its NWay ability. If the Link partner also supports Flow Control, then the RTL8201E(L) can
recognize the Link partner’s NWay ability by examining bit 10 of ANLPAR (register 5).
Single-Chip/Port 10/100 Fast Ethernet PHYceiver
with Auto MDIX
20
Track ID: JATR-1076-21 Rev. 1.3
REALTEK [ Realtek Semiconductor Corp. ]
