RTL8208B-LF/RTL8208BF-LF
Datasheet
7.8. Power Saving and Power Down Mode
7.8.1. Power Saving Mode
The RTL8208B(F)-LF implements power saving mode on a per-port basis. A port automatically enters
power saving mode ten seconds after the cable is disconnected from it. Once a port enters power saving
mode, it transmits normal link pulses only on its TXOP/TXON pins and continues to monitor the
RXIP/RXIN pins to detect incoming signals, which might be the 100Base-TX MLT-3 idle pattern,
10Base-T link pulses, or Auto-Negotiation’s FLP (Fast Link Pulse). After it detects an incoming signal, it
wakes up from power saving mode and operates in normal mode according to the result of the connection.
Power saving mode is not supported when in 100FX operation.
7.8.2. Reg0.11 Power Down Mode
The RTL8208B(F)-LF implements power- down mode on a per-port basis. Setting MII Reg.0.11 forces
the corresponding port of the RTL8208B(F)-LF to enter power down mode. This disables all
transmit/receive functions on that port.
7.9. LED Configuration
7.9.1. Serial LEDs
The RTL8208B(F)-LF supports serial LED status streams for LED display. The forms of LED status
streams, shown below, are controlled by LEDMODE[1:0] pins, which are latched upon reset. All LED
statuses are represented as active-low, except Link/Act in Bi-color LED mode, whose polarity depends on
Spd status.
Table 30. Serial LED Mode
LEDMODE[1:0]
Mode
3-bit serial stream
2-bit serial stream
3-bit for Bi-color LED Col/Fulldup, Link/Act, Spd
1-bit serial stream Link/Act/Spd
Output Sequences
Col/Fulldup, Link/Act, Spd
Spd, Link/Act
00
01
10
11
Single-Chip Octal 10/100-TX/FX PHY Transceiver
38
Track ID: JATR-1076-21 Rev. 1.3
REALTEK [ Realtek Semiconductor Corp. ]
