I am working on design of custom board with SAME53J19A.
Device package is TQFP64.
My plan was to follow board [SAME54 Xplained Pro] and copy its RMII interconnection between SAME54P20A (128-pin) and Phy KSZ8091.
But I have found there is not available pin PC20 GMAC/GRXDV on 64-pin and 48-pin devices.
Q1) Is this signal necessary for RMII ?
Q2) If it can be omitted - what is then connected to pin_15 of KSZ8091 (signal CRS_DV/PHYAD) ?
Q3) If it can be omitted - what changes need to be made in configuration ?
I would like to use Atmel Start project (for [SAME54 Xplained Pro]) / "LwIP socket api example", on DASHBOARD is module COMMUNICATION_IO where can be selected pins for RMII;
for my 64-pin device is probably necessary to do:
- change GMDC from PC11 (not available) to PA20
- change GMDIO from PC12 (not available) to PA21
- uncheck GRXDV (PC20, not available, not possible to remap)
Would be great if anybody could show an example of 64 or 48-pin microcontroller interconnection to Phy (whatever type) + configuration used.
I am not able to find any other board to copy, there is no guidance in datasheet, no app note, no tutorial..
Any partial comments welcome as well.