The following is a Screen Script associated as the "While Showing" Script for a Video Display. It rotates between 3 cameras. It uses a local tag file with screen tag named count.
SETVAL "count=%PLUS 1"
if {[GETVAL count] > 60} then {
SETVAL "page=%LOOPPLUS 1"
switch [GETVAL page] \
"1" {GOTO URL=vdo:camviewlc#ip=210.128.176.51} \
"2" {GOTO URL=vdo:atoplc#ip=67.94.27.161&port=0} \
"3" {GOTO URL=vdo:atoplc#ip=202.178.230.25&port=0} \
"default" {GOTO URL=vdo:atoplc#ip=202.178.230.25&port=0}
SETVAL count=0
}