DP83867IR: DP83867 strap configuration

Yu Lan

Part Number: DP83867IR

For the PHY IC DP83867, when I do the strap configuration.

The datasheet shows that the default code of pin RX_CTRL is [00], which belongs to MODE1 and indicates enable the Auto-negotiation.

From datasheet, The MODE3 also enables the Auto-negotiation.

So, if I want to enable the Auto-negotiation, MODE1 and MODE3 are both OK, right?

But I found the strap configuration of RX_CTRL pin in TI demo board SK-64B_SCH is MODE3.

It confused me, why did they choose the MODE3 instead of MODE1?

Are there some other reasons？

11 months ago

0 Melissa Chang 11 months ago

TI__Expert 8435 points

Hi Yu,

Strap modes 1 and 2 are not applicable for RX_DV/RX_CTRL. The RX_DV/RX_CTRL strap must be configured for strap mode 3 or strap mode 4. If the RX_CTRL pin cannot be strapped to mode 3 or mode 4, bit[7] of Configuration Register 4 (address 0x0031) must be cleared to 0. Autoneg Disable should always be set to 0 when using gigabit Ethernet.

Best regards,

Melissa

0 Yu Lan 11 months ago in reply to Melissa Chang

Prodigy 20 points

Would you please tell me where I can find this requirements---"Strap modes 1 and 2 are not applicable for RX_DV/RX_CTRL. The RX_DV/RX_CTRL strap must be configured for strap mode 3 or strap mode 4. "