Having trouble getting link up on Ethernet with esp32 MCU

Thread Starter


Joined Nov 14, 2021
Hello all,

I have an issue regarding ethernet with esp32, So i have got designed a hardware with esp32 and dp83848 phy for ethernet connection. The problem is i dont get Link Up from phy. I am running esp32 example code PHY reset pin is 32. this is log output from board, it just stops at Ethernet started,

V (2958) tcpip_adapter: check: local, if=2 fn=0x400e24d8


V (2958) tcpip_adapter: call api in lwip: ret=0x0, give sem[0m

V (2958) tcpip_adapter: check: remote, if=2 fn=0x400e24d8


D (2968) event: running post ETH_EVENT:0 with handler 0x400d3a84 on loop 0x3ffb4f7c[0m

[0;32mI (2978) eth_example: Ethernet Started[0m
I checked the communication between phy and esp32, this sounds good, as i tried to read phy register and below was output, i had used cyclone TCP example code for this., so this conclude phy and esp32 are communicating,

Initializing DP83848...

PHY reg: 00: 0x3100

PHY reg: 01: 0x7849

PHY reg: 02: 0x2000

PHY reg: 03: 0x5C90 (this is phy address)

PHY reg: 04: 0x01E1

PHY reg: 05: 0x0000

PHY reg: 06: 0x0004

PHY reg: 07: 0x2001

PHY reg: 08: 0x0000

PHY reg: 09: 0x0000

PHY reg: 10: 0x0000

PHY reg: 11: 0x0000

PHY reg: 12: 0x0000

PHY reg: 13: 0x0000

PHY reg: 14: 0x0000

PHY reg: 15: 0x0000

PHY reg: 16: 0x0000

PHY reg: 17: 0x0000

PHY reg: 18: 0x0000

PHY reg: 19: 0x0000

PHY reg: 20: 0x0000

PHY reg: 21: 0x0000

PHY reg: 22: 0x0100

PHY reg: 23: 0x0021

PHY reg: 24: 0x0000

PHY reg: 25: 0x8021

PHY reg: 26: 0x0904

PHY reg: 27: 0x0000

PHY reg: 28: 0x0000

PHY reg: 29: 0x6011

PHY reg: 30: 0x003F

PHY reg: 31: 0x0000
so now i have to check between RJ45 jack and PHY, i actually dont understand what is the issue, but i am sure its between phy and RJ45 jack,

i have tried the connection with router and PC directly, also tried using different LAN cable, but didnt work

this is datasheet of RJ45 jack

Here's Schema :
So any help regarding this will be grateful, if any more information is needed kindly tell me.