SNLS779A July 2025 – November 2025 DP83TC815-Q1
PRODUCTION DATA
The SMI function of the DP83TC815-Q1 supports read or write access to the extended register set using registers REGCR (0x0D) and ADDAR (0x0E) and the MDIO Manageable Device (MMD) indirect method defined in IEEE 802.3ah Draft for Clause 22 for accessing the Clause 45 extended register set.
Registers with addresses above 0x001F require indirect access. For indirect access, a sequence of register writes must be followed. The MMD value defines the Device Address (DEVAD) of the register set. The DEVAD must be configured in the register 0x000D (REGCR) bits [4:0] for indirect access
The DP83TC815-Q1 supports 3 MMD device addresses:
| MMD REGISTER SPACE | REGISTER ADDRESS SETTING |
|---|---|
| MMD1F | 0x000 - 0x0DF0 |
| MMD1 | 0x1000 - 0x1836 |
| MMD3 | 0x3000 - 0x3001 |
The following sections describe how to perform operations on the extended register set using register REGCR and ADDAR. The descriptions use the device address for MMD1F register accesses (DEVAD[4:0] = 11111).