We have two DP83848H with separate I/O except they share a common MDC/MDIO. Unfortunately, neither have pulling/strapping resistors on the PHYAD pins, thus at power-on they have the same address.
The datasheet states the address is set after hardware reset RESET_N is pulsed low for > 1uS.
Can the address be set by holding RESET_N low, then driving the address onto the RXD pins, releasing RESET_N and putting the RXD pins back to receive mode.
The reset timing diagram 8.2.2 does not state the hold-time necessary for PHYAD after reset is deasserted.
We are concerned the PHYAD pins will transition to output drivers before we have returned the RXD pins to inputs, thus both will be driving at the same time.
1. Is the hold-time available
2. Has anybody had success programming the PHYAD this way?
Thank you, Roland