Marshall Amplification CV630-IP - Maintenance and System Information

CV630-IP RS-232 Command Set
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17.11 Payload length
Stores the number of bytes (1 to 16) of data is stored on the payload.
Example: when the payload length is 16 bytes.
Byte 2:00h
Byte 3:10h
17.12 Sequence number
The controller stores the sequence number that is added every time a message is
sent. If the sequence number reaches the limit, next values will be 0. The peripheral
device saves the sequence number in the message from the controller, and stores
the sequence number of the received message corresponding to the message sent
to the controller.
17.13 Payload
Depending on the payload type, the following are stored.
VISCA command
Stores the packet of the VISCA command.
VISCA inquiry
Stores the packet of VISCA message.
VISCA reply
Stores the reply for the command or inquiry (Acknowledge message,
completion message, or error message).
VISCA device setting command
Stores the packet of the VISCA device setting command.
Control command
The following are stored on the payload division of the control command.
Controlled reply
The following are stored on the payload division of the reply for the control
command.
17.14 Delivery confirmation
VISCA over IP uses UDP as a communications protocol of the transport layer. Delivery
of messages is not guaranteed for the UDP communication. Delivery confirmation
and retransmission should be performed on the application.
When the controller sends a message to the peripheral device, wait until a reply for
the message is received before sending the next message. You can confirm delivery
of messages by managing the time-out waiting for a reply message sent.
If time out occurs on the controller, loss of one of the following message is considered:
Command
Acknowledge message
Completion message for command
Inquiry
Reply message for the inquiry
Error message
Inquiry of the VISCA device setting command
Reply message of the VISCA device setting command.