STM32F4XX HAL ETH initial LAN8720A bug

[liu yong]

Posted on August 08, 2017 at 09:43

My hardware is F429 + LAN8720A, firmware is STM32Cube_FW_F4_V1.16.0

when power up, everything is ok,  PHY_BCR = 0x3100, phy link up, at this time I just reset f429, 

PHY_B

C

R = 0x2100, PHY link failed, and the two leds are off.Here are some codes in the HAL driver:

My question is after reset we should set the BCR, but the HAL driver reset the BCR, then just wait link up, is that right?

[liu yong]

Posted on August 08, 2017 at 09:57

F429 reset pin and LAN8720A  reset pin use the same reset signal. I use the HAL_NVIC_SystemReset() to soft reset F429.

Now I add HAL_ETH_WritePHYRegister(heth, PHY_BCR, PHY_AUTONEGOTIATION) after  HAL_Delay(PHY_RESET_DELAY);