CV620-IP / CV620-NDI RS-232 Command Set
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Pic. 1 Packet structure
Note:
Pic. 1 shows the packet structure, while Pic.2 shows the actual waveform. Data flow will take place
with the LSB first.
Pic. 2 Actual waveform for 1 byte
21. Communication method of VISCA over IP
21.1 Communication Method
VISCA over IP can process the VISCA communication between the controllers and peripheral
devices using the messages that can be identified on the LAN, and sends/receives them.
Because of this, VISCA over IP is not concerned about the contents of the communication
between the controllers and peripheral devices. However, the VISCA communication sequence is
different, depending on the types, as follows.
21.2 VISCA command
This is a command from the controller to the peripheral device. When the peripheral device receives
this command, Acknowledge is returned. After completing command processing, a completion
notice is returned. This command uses the socket of VISCA. The order of completion notices may be
changed if the multiple commands are sent to the same peripheral device.
21.3 VISCA inquiry
This is an inquiry from the controller to the peripheral device. When the peripheral device receives
this type of command, the reply for the inquiry is returned. This command does not use the socket of
VISCA. The order of the replies is not changed if a multiple commands are sent.
21.4 VISCA reply
This is an Acknowledge, completion notice, reply, or error reply from the peripheral device to the
controller. The classification for sending messages from the peripheral device to the controller is
common.
21.5 VISCA device setting command
This is the device setting command from the controller to the peripheral device. When the peripheral
device receives this classifications command, the peripheral device performs the function depend on
the command.
21.6 Address
Sets the address of the peripheral device, and does not return a reply to the controller. While using
VISCA over IP, the address command is not sent from the controller because a Network Change
command from the peripheral device that triggers sending command is not issued.
21.7 IF_Clear
Sends the reply message to the controller after clearing, without using VISCA socket.
21.8 CAM_VerslonInq
Sends the reply message to the controller, without using VISCA socket.
21.9 Format
These are the specifications of the message header (8 bytes) and payload (1 to 16 bytes).
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