It's preferred to use a IP reservation on the router for ALL devices connected to the 655 router.
Thanks FurryNuts. Actually for historical reasons, the older computers on the network including WHS NAS machines have fixed IPs. Of course, the DIR-655 doesn't do "Reservation" on fixed IPs because that would be redundant. On more recent addons to the network, I typically set them up as "Auto" and then reservere the IP on the DIR-655. I'm hesitant to change the fixed IP machines to the same model because they operate on a different physical branch of the network, and can on occaision find themselves working independently.
BTW: I'd already applied the other recommendations
But this printer was setup using the WPS "pin" method and ended up visible from the PCs but missing from the Mac. But I found a solution:
Using the free
Fing DOS network discovery program on the PC, I found the IP address, Mac address and exact Hostname of the printer. I then set the an IP Reservation on the DIR-655 entering those parameters. And it worked! The Mac woke the printer and now prints.
Odd thing: on the Network\Settings page, the IP reservations shows the printer name and correct IP, but on the Setup\Wireless page the IP is still 0.0.0.0.
But it does work. I'll see if it sticks over the next few days and report back if it doesn't.