The DP83869HM supports two types of Bridge Modes to translate data between two MAC interface types. The two types are:
- RGMII-to-SGMII mode
- SGMII-to-RGMII mode
The naming convention implies MAC-to-PHY and the functionality of the DP83869HM changes depending on which mode is selected. More information can be found in the Bridge Modes section of the data sheet.
The purpose of this FAQ is to clarify a misleading register setting in the data sheet. The DP83869HM has several different operating modes which can be configured by adjusting the OPMODE. This can be adjusted by writing to Register 0x1DF.
When using Bridge Mode, the OPMODE should be configured as 0x3. Bit 6 of Reg 0x1DF determine which type of bridge mode you go into. The bit description of bit 6 in SNLS614C is flipped. The correct table is listed below. This means that:
- Reg 0x1DF = 0x0043
- configures the DP83869HM into RGMII-to-SGMII Bridge
- Reg 0x1DF = 0x0003
- configures the DP83869HM into SGMII-to-RGMII Bridge
| Bit | Field | Type | Reset | Description |
| 15-9 | RESERVED | R | 0h | Reserved |
| 8-7 | RESERVED | R | 0h | Reserved |
| 6 | BRIDGE_MODE_RGMII_MAC | R/W | 1h |
0h = SGMII to RGMII Bridge 1h = RGMII to SGMII Bridge |
| 5 | RGMII_MII_SEL | R/W | 0h | |
| 4 | RESERVED | R | 0h | Reserved |
| 3 | RESERVED | R | 0h | Reserved |
| 2-0 | CFG_OPMODE | R/W | 0h |
Operation Mode 0h = RGMII to Copper 1h = RGMII to 1000Base-X 2h = RGMII to 100Base-FX 3h = RGMII to SGMII 4h = 1000Base-T to 1000Base-X 5h = 100Base-TX to 100Base-FX 6h = SGMII to Copper 7h = Reserved |