SNLS614A September 2018 – December 2018 DP83869HM
In media convertor mode, DP83869HM will translate data between copper and fiber interface for 1000M and 100M speeds. Media convertor mode can be activated through the straps. The DP83869HM supports Managed Media Convertor mode.
In Managed mode, Media Convertor can still be activated via straps but register configuration option are also used. When Media Convertor Mode is enabled then bit  of register 0x01EC should be set to 0. Enhanced features like changing LED configuration, Capabilities programming broadcasted in Auto-Neg etc may need configuration and are supported through register programming. Register access to the PHY is retained. This provides additional flexibility to use other features supported by the PHY.
1000BASE-X link needs monitoring in the rare case that link is not established. It is recommended to use the application note DP83869 1000Base-X Link Detection(SNLA305) for identifying 1000Base-X link. This monitoring is not needed in 100M media convertor mode.
Copper interface will support auto-negotiation, but the user will have to ensure that the speed negotiated on the copper side matches the speed fixed on the fiber side. In cases of speed mismatch between copper and fiber, interface data transmission will not be successful.
The DP83869HM also supports Link Loss Pass Through in 100M mode. In a network containing two media convertors where the link is dropped on one end of the system, a link loss indication is passed through all the way to the far end. The Link Loss Pass-Through is enabled or disabled through straps. An example is shown in Figure 27.