Appendix A: Technical Specifications
84
Table 14 lists the RJ-45 pin signals for the two 10/100/1000-Base-T ports
on the AT-8550GB switch when the ports are operating at 1000 Mbps.
4 Unused Unused
5 Unused Unused
6 RX- and Vport-2 TX- and Vport-2
7 Unused Unused
8 Unused Unused
1. Vport-1 can be positive (+) or negative (-), depend-
ing on the requirements of the powered device con-
nected to a port.
2. Vport-2 can be positive (+) or negative (-), depend-
ing on the requirements of the powered device con-
nected to a port. If Vport-1 is positive, then Vport-2
will be negative. If Vport-1 is negative, then Vport-2
will be positive.
Table 14. MDI and MDI-X Pin Signals (1000Base-T)
MDI Configuration MDI-X Configuration
Pinout Pair Pinout Pair
1 Pair 1 + 1 Pair 2 +
2 Pair 1 - 2 Pair 2 -
3 Pair 2 + 3 Pair 1 +
4 Pair 3 + 4 Pair 4 +
5 Pair 3 - 5 Pair 4 -
6 Pair 2 - 6 Pair 1 -
7 Pair 4 + 7 Pair 3 +
8 Pair 4 - 8 Pair 3 -
Table 13. 10/100Base-T Port MDI/MDI-X Pin Signals with PoE
Pin MDI Signal MDI-X Signal