MISO pin during RST


#1

I’m using a Wiz550io v1.1. I share the SPI bus with an EEPROM. The Wiz550io seems to be pulling down the MISO line when the RSTn line is low. This is preventing communication with the EEPROM. Has anyone else experienced this?

I wanted to keep the wiz550io in reset until the user settings were loaded from the EEPROM. Then release the Wiz550io from reset.


#2

Hi bpowers.

The MISO of WIZ550io is connected with internal MCU.

When WIZ550io’s reset is set low, MCU is reset.

Therefore, while Reset is low, the state of MISO is expected to be low.

But you do not have to worry about this.

When you are communicating with the EEPROM, you do not need to reset WIZ550io.

WIZ550io’s CS pin should be set High to communicate with EEPROM.

Scott