IXF1104
5.4.2Timing Specifics
The IXF1104 RGMII complies with RGMII Rev1.2a requirements. Table 27 provides the timing specifics.
5.4.3TX_ER and RX_ER Coding
To reduce interface power, the transmit error condition (TX_ER) and the receive error condition (RX_ER) are encoded on the RGMII interface to minimize transitions during normal network operation (refer to Table 28 on page 96 for the encoding method). Table 27 provides signal definitions for RGMII.
Table 27. RGMII Signal Definitions
IXF1104 | RGMII |
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Standard | Source | Description | ||
Signal | ||||
Signal |
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TXC_0:3 | TXC | MAC | Depending on speed, the transmit reference clock is 125 MHz, 25 MHz, | |
or 2.5 MHz +/– 50ppm. | ||||
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TD[3:0]_n | TD<3:0> | MAC | Contains register bits 3:0 on the rising edge of TXC and register bits 7:4 | |
on the falling edge of TXC. | ||||
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TX_EN | TX_CTL | MAC | TXEN is on the leading edge of TXC. | |
TX_EN xor TX_ER is on the falling edge of TXC. | ||||
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RXC_0:3 | RXC | PHY | Continuous reference clock is 125 MHz, 25 MHz, or 2.5 MHz +/– 50 | |
ppm. | ||||
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RD[3:0]_n | RD<3:0> | PHY | Contains register bits 3:0 on the leading edge of RXC and register bits | |
7:4 on the trailing edge of RXC. | ||||
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RX_DV | RX_CTL | PHY | RX_DV is on the leading edge of RXC. | |
RX_DV or RXERR is the falling edge of RXC. | ||||
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The value of RGMII_TX_ER and RGMII_TX_EN are valid at the rising edge of the clock while TX_ER is presented on the falling edge of the clock. RX_ER coding behaves in the same way (see Table 28, Figure 19, and Figure 20).
Table 28. TX_ER and RX_ER Coding Description
Condition |
| Description | |
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Receiving valid frame, | RX_DV = true |
| RX_ER = false |
no errors | Logic High on rising edge of RXC |
| Logic High on the falling edge of RXC |
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Receiving valid frame, | RX_DV = true |
| RX_ER = true |
with errors | Logic High on rising edge of RXC |
| Logic Low on the falling edge of RXC |
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Receiving invalid frame | RX_DV = false |
| RX_ER = false |
(or no frame) | Logic Low on rising edge of RXC |
| Logic Low on the falling edge of RXC |
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Transmitting valid frame, | TX_EN = true |
| TX_ER =false |
no errors | Logic High on rising edge of TXC |
| Logic High on the falling edge of TXC |
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Transmitting valid frame | TX_EN = true |
| TX_ER = true |
with errors | Logic High on rising edge of TXC |
| Logic Low on the falling edge of TXC |
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Transmitting invalid | TX_EN = false |
| TX_ER = false |
frame (or no frame) | Logic Low on rising edge of TXC |
| Logic low on the falling edge of TXC |
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NOTE: Refer to Figure 19 for TX_CTL behavior, and Figure 20 for RX_CTL behavior. | |||
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96 | Datasheet |
Document Number: 278757
Revision Number: 007
Revision Date: March 25, 2004
