DP83867IS: Method for preventing packet loss when IFG<12Bytes

Part Number: DP83867IS

Hi,

1.Could you tell me how the internal behavior of PHY changes depending on the setting value (0x5/0x4/0x3) of VTM_CFG (address 0x 0053)?

2.Could you tell me the conditions and cases where using 0x3 is recommended?

The background of this question is as follows.

When a product equipped with DP83867 is connected to an external Ethernet SW, packet loss occurs. When I changed the setting value of VTM_CFG (address 0x0053) from 0x5 to 0x4, which is a countermeasure for IFG<12 bytes, packet loss was improved. On the other hand, when I changed from 0x4 to 0x3, the symptom became worse. In the future, I would like to proceed with 0x4, so I would like to check the characteristics of each setting value.

https://www.ti.com/lit/an/snla246d/snla246d.pdf?ts=1789074981510

Best Regards,

Nishie