What setting do I need to use GS-LPD for network printing?

To enable network printing, set /etc/printcap as follows:
When using LP7700, set:
LP7700:\
:rm=192.168.1.1:\ <- IP Address
:sh:\
:if=/usr/local/bin/filter7700:\
:sd=/var/spool/lpd/LP7700:\
:mx#0:

For your information, when your printer is connected locally (with either parallel or USB), you must set /etc/printcap as follows:
LP7700:\
:lp=/dev/lp0:\
:sh:\
:if=/usr/local/bin/filter7700:\
:sd=/var/spool/lpd/LP7700:\
:mx#0: