Control Marshall CV-620 camera (rs232)

Damian

Hi all! I am trying to integrate to an AMX system (NX2200) a Marshall CV610-BK2 camera. The connection port is serial. Already configure the dip switch of the camera and check that the communication parameters (9600, N, 8.1) and the cable pin are correct. I try to receive some answer from the camera but it does not answer absolutely anything.
I only receive an answer when I unplug the camera's power and plug it back in (it automatically sends it when it restarts)

• "String From [5001: 4: 1] - [$ 908 $ FF]" (I can not find that answer anywhere in the control protocol manual)

I tried sending a lot of diferent strings, but nothing works

SEND_STRING dvCAMPUBLICO,"$80,$01,$04,$00,$02,$FF"
SEND_STRING dvCAMPUBLICO,"$80,$01,$04,$00,$02,$FF,$0D"
SEND_STRING dvCAMPUBLICO,"$80,$01,$04,$00,$02,$FF,$0D,$0A"
SEND_STRING dvCAMPUBLICO,"$81,$01,$04,$00,$02,$FF"
SEND_STRING dvCAMPUBLICO,"$82,$01,$04,$00,$02,$FF"
SEND_STRING dvCAMPUBLICO,"$80,$01,$04,$07,$02,$FF,$0D,$0A"
SEND_STRING dvCAMPUBLICO,"$0D,$80,$01,$04,$07,$02,$FF,$0D,$0A"
and more combinations...

Someone succeeded with these cameras, can you tell me something to keep in mind?
Thank you in advance