SNLS614A September 2018 – December 2018 DP83869HM
PRODUCTION DATA.
Far-end (Reverse) Loopback is a special test mode to allow testing the PHY from the link-partner side. In this mode, data that is received from the link partner passes through the PHY's receiver is looped back at the MAC interface and is transmitted back to the link partner. While in Reverse Loopback mode, all data signals that come from the MAC are ignored. Through register configuration, data can also be transmitted onto the MAC Interface.
The availability of Loopback depends on the operational mode of the PHY. The Link Status in these loopback modes is also affected by the operational mode. Table 4 lists out the exceptions where Loopbacks are not available.
OP MODE | LOOPBACK | EXCEPTION |
---|---|---|
Copper | PCS | 10M |
Fiber | MII | 100M |
PCS | 100M | |
Analog | 100M, 1000M | |
SGMII to RGMII | PCS | 10M, 100M, 1000M |
Digital | 10M, 100M, 1000M | |
Analog | 10M, 100M, 1000M | |
External | 10M, 100M, 1000M | |
RGMII to SGMII | PCS | 10M, 100M, 1000M |
External | 10M, 100M, 1000M | |
Media Convertor | MII | 100M, 1000M |
Analog | 100M on Fiber Interface | |
External | 100M on Fiber Interface | |
100M, 1000M on Copper Interface |