W5500 PHY Operation Mode Select - Hardware vs Software

My understanding is that the PHY operation mode can be set by either PMODE2 - PMODE0 (pin #43 - #45) or the software
* @ingroup DATA_TYPE
* It configures PHY configuration when CW_SET PHYCONF or CW_GET_PHYCONF in W5500,
* and it indicates the real PHY status configured by HW or SW in all WIZCHIP. \n
* Valid only in W5500.
typedef struct wiz_PhyConf_t
uint8_t by; ///< set by @ref PHY_CONFBY_HW or @ref PHY_CONFBY_SW
uint8_t mode; ///< set by @ref PHY_MODE_MANUAL or @ref PHY_MODE_AUTONEGO
uint8_t speed; ///< set by @ref PHY_SPEED_10 or @ref PHY_SPEED_100
uint8_t duplex; ///< set by @ref PHY_DUPLEX_HALF @ref PHY_DUPLEX_FULL
//uint8_t power; ///< set by @ref PHY_POWER_NORM or @ref PHY_POWER_DOWN
//uint8_t link; ///< Valid only in CW_GET_PHYSTATUS. set by @ref PHY_LINK_ON or PHY_DUPLEX_OFF
} wiz_PhyConf;

Since the software can override the hardware, why do we even have these PMODEx pins at the first place? Is there anything the hardware can do but the software can’t?

Hi acpie360

The two methods are simply the difference between software and hardware.

thank you