Help getting the URI right

Setup redhat 9
Printer on 3 port  print server connected parrallel to server
Print server at 192.168.0.13
Printer is an EPSON color 900
cups-config --version
1.1.17


Walking thru the cups config http interface I have a selection of
examples for possible URI schemes:
    file:/path/to/filename.prn
    http://hostname:631/ipp/
    http://hostname:631/ipp/port1
    ipp://hostname/ipp/
    ipp://hostname/ipp/port1
    lpd://hostname/queue
    socket://hostname
    socket://hostname:9100
        
Print is named EP in the cups config interface.

To use either ipp or http protocol  what should my URI look like?

Using: Device URI: http://192.168.0.13:631/ipp/lp1

Doesn't throw any errors and leaves this in the access log... but
doesn't print.
 
localhost - root [15/Sep/2003:23:17:46 -0500] "GET 
/admin/?op=stop-printer&printer_name=EP HTTP/1.1" 200 1530
localhost - root [15/Sep/2003:23:17:57 -0500] "GET /cups.css HTTP/1.1" 304 0
localhost - root [15/Sep/2003:23:18:00 -0500] "GET 
/printers/EP?op=print-test-page HTTP/1.1" 200 0
localhost - - [15/Sep/2003:23:18:00 -0500] "POST /printers/EP HTTP/1.1" 200 
14975
localhost - root [15/Sep/2003:23:18:00 -0500] "GET /cups.css HTTP/1.1" 304 0
localhost - root [15/Sep/2003:23:18:00 -0500] "GET 
/printers/EP?op=print-test-page HTTP/1.1" 200 1529