JAJSLL2B April 2021 – November 2021 DP83561-SP
PRODUCTION DATA
In some applications, the orientation of the cable connector can require Copper PMD traces to cross over each other. This complicates the board layout. The DP83561-SP can resolve this issue by implementing mirroring of the ports inside the device. Normal and Mirror modes offer flexibility to mount the RJ45 connector on either the top or bottom layer without any undesired cross-overs of differential signals, as shown in Figure 7-10.
In 10/100 operation, the mapping of the port mirroring is shown in Table 7-2. When using mirror mode in 100-Mbps mode, TI recommends that the user read register 0xA1 and write the same value in register 0xA0. The steps are as follows:
MDI MODE | MIRROR PORT CONFIGURATION |
---|---|
MDI | A → D |
B → C | |
MDIX | A → D |
B → C |
In Gigabit operation, the mapping of the port mirroring is:
MDI MODE | MIRROR PORT CONFIGURATION |
---|---|
MDI or MDIX | A → D |
B → C | |
C → B | |
D → A |
Mirror mode can be enabled through strap or through register configuration using the Port Mirror Enable bit in the CFG4 register (address 0x0031). In Mirror mode, the polarity of the signals is also reversed.
Table 7-4 shows which pin/channel corresponds to which signal line in normal and mirror mode.
DP83561-SP | Normal Mode | Mirror Mode | |||||
---|---|---|---|---|---|---|---|
Pin | Channel | 1000 M Mode | 100M MDI Mode | 100M MDIX Mode | 1000 M Mode | 100M MDI Mode | 100M MDIX Mode |
1 | A | Td_P_A (+) | Td_P_A ( Tx+) | Td_P_A ( Rx+) | Td_M_D(-) | ||
2 | A | Td_M_A (-) | Td_M_A ( Tx-) | Td_M_A (Rx-) | Td_P_D(+) | ||
4 | B | Td_P_B(+) | Td_P_B ( Rx+) | Td_P_B ( Tx+) | Td_M_C (-) | ||
5 | B | Td_M_B (-) | Td_M_B (Rx-) | Td_M_B ( Tx-) | Td_P_C(+) | ||
7 | C | Td_P_C(+) | Td_M_B (-) | Td_M_B (Rx-) | Td_M_A ( Tx-) | ||
8 | C | Td_M_C (-) | Td_P_B(+) | Td_P_B ( Rx+) | Td_P_A ( Tx+) | ||
10 | D | Td_P_D(+) | Td_M_A (-) | Td_M_A ( Tx-) | Td_M_B (Rx-) | ||
11 | D | Td_M_D(-) | Td_P_A (+) | Td_P_A ( Tx+) | Td_P_B ( Rx+) |