RTL8211C & RTL8211CL
Datasheet
6. Function Description
6.1. Transmitter
Based on state-of-the-art DSP technology and mixed-mode signal processing technology, the
RTL8211C(L) is capable of operating at 10/100/1000Mbps link speed over standard CAT.5 UTP cable and
CAT.3 UTP cable (10Mbps).
6.1.1. RGMII (1000Mbps) Mode
The RTL8211C(L)’s PCS layer receives data bytes from the MAC through the RGMII interface and
performs the generation of continuous code-groups through 4D-PAM5 coding technology. Then those code
groups are passed through a waveform-shaping filter to minimize EMI effect, and are transmitted onto the
4-pair CAT5 cable at 125MBaud/s through a D/A converter.
6.1.2. RGMII (100Mbps) Mode
The transmitted 4-bit nibbles (TXD[3:0]) from the MAC, clocked at 25MHz (TXC), are converted into 5B
symbol code through 4B/5B coding technology, then through scrambling and serializing, are converted to
125MHz NRZ and NRZI signals. After that, the NRZI signal are passed to the MLT3 encoder, then to the
D/A converter and transmitted onto the media.
6.1.3. RGMII (10Mbps) Mode
The transmit 4-bit nibbles (TXD[3:0]) from the MAC, clocked at 2.5MHz (TXC), are serialized into
10Mbps serial data. Then the 10Mbps serial data is converted into a Manchester-encoded data stream and is
transmitted onto the media by the D/A converter.
6.2. Receiver
6.2.1. RGMII (1000Mbps) Mode
Input signals from the media first pass through the on-chip sophisticated hybrid circuit to subtract the
transmitted signal from the input signal for effective reduction of near-end echo. Afterwards, the received
signal is processed with state-of-the-art technology, such as adaptive equalization, BLW (Baseline
Wander) correction, cross-talk cancellation, echo cancellation, timing recovery, error correction, and
4D-PAM5 decoding. Then, the 8-bit-wide data is recovered and is sent to the RGMII interface at a clock
speed of 125MHz. The Rx MAC retrieves the packet data from the receive RGMII interface and sends it to
the Rx Buffer Manager.
Integrated 10/100/1000 Gigabit Ethernet Transceiver
9
Track ID: JATR-1076-21 Rev. 1.3
ETC [ ETC ]
