Hello
You fail to mention which operating system you are using. I use Mac OSX and Debian Linux so my answer is from that background. You also do not mention which version of iPad and IOS version of the iPad you are using.
I have some questions.
Have you downloaded the online manual for the printer?
Are you printing directly from the iPad to the printer or is the printer connected to your computer and the computer sharing the printer?
Does the iPad see the printer?
When you select the Printer Option on the iPad, is the name of the pritner shown next to the "Printer" prompt.
If it is not shown are you able to select it?
if you are not able to select it, that may be an indication that the printer and the iPad are on different networks.
Are you able to connect to the internet with the iPad? If you are that is further indication that the printer and the iPad are on different networks. What is the IP Address assigned to the iPad? I assume that it is a DHCP assigned address.
It is difficult to give a good answer because you have provided so little information to go on. Basically, i think you have a mismatch between DHCP assigned IP addresss. The Comcast Router box is probably the DHCP Server for both WIFI and Ethernet. You need to reset the printer's network settings so it receives a new DHCP assigned IP address which is in the same IP pool as the IP address assigned to the iPad.
on the Printer do the following.
make sure there is paper in the printer
make sure the printer is turned on
press the maintenance button repeatedly until the LED displays what looks like an upsidedown Capital U.
press the color button or the black button and the printer should start printing the network setting.
Once that has printed look at the line:
IP Address XXX.XXX.XXX.XXX
Default Gateway XXX.XXX.XXX.XXX
the default gateway should be the same gateway shown in the iPad.
the IP address should be in the same IP Pool as the iPad.
If all else fails download the manual and read it.
