Second Ethernet TX_EN on i.MX7 using RMII interface

The Colibri data sheet says the TXEN signal from the iMX7 to the PHY is the ALT3 function of the EPDC_GDRL ball. Yet the i.MX 7D reference manual from NXP/Freescale doesn’t define an ALT3 function on that pin. There’s also no ALT3 definition for that pin in the device tree bindings. It appears that the correct connection is to EPDC_GDRL ALT2. Is this correct? Is the Colibri data sheet in error, or is there something else we’re missing?

Hi @systemix,

Thank you for sharing the details.
We will recheck the details and make the correction in the datasheet if required.
I will keep you updated on the issue.

Thank you again.

Best Regards,
Satyan Raj

Thank you for reporting that inconsistency. Our datasheet was based on an older pin muxing table from NXP. In this table, the TXEN was listed as dedicated function on ALT3 of the EPDC_GDRL pin. They removed that in later versions. We will update our datasheet as well as the Pinout Designer Database in the next revision.