Setting the W550io in to sleep or Low power mode


I have the W550io board connected to an ESP8266 device using the ESP8266 arduino library. it is functioning normally, and I can send and receive packets. I am using this W550io libary created by Wiznet

I would like to turn off or reduce the power consumption of the W550io board as much as possible. After the W550io is put into low power mode I will not need to wake it up until the entire system is power cycled.

Q1) How do I force the Wiznet W550io to use 10mb connection instead of 100mb? As described here
Q2) How do I force the Wiznet W550io into using low power mode or shut off the PHY?


I have tried the following code snippet to turn off the Phy, but the LEDs are still illuminated and consuming power.
This code snippet came from this post Power down PHY from Arduino Mega

This did not work.

int readback = W5100.getPHYCFGR(); Serial.print("readback of the phys: "); Serial.println(readback); W5100.setPHYCFGR(0b10110000);