SNLS647G december 2019 – july 2023 DP83826E , DP83826I
PRODUCTION DATA
MII Loopback is the shallowest loop through the PHY. It is a useful test mode to validate communications between the MAC and the PHY. When in MII Loopback, data transmitted from a connected MAC on the TX path is internally looped back in the DP83826 to the RX pins where it can be checked by the MAC.
MII Loopback is enabled by setting bit[14] in the BMCR and bit[2] in BISCR.