Telycam 20X NDI, Руководство пользователя

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NDI
®
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Name Value Description
RESET 0x01 Resets the sequence number to 0.
The value that was set as the
sequence number is ignored.
ERROR 0x0Fyy yy=01:Abnormality in the
sequence number.
yy=02:Abnormality in the
message(message type).

Controlled reply
The following data is saved in return command payload of control command.
Message Value Description
ACK 0x01 Reply for RESET.
Delivery confirmation
VISCA over IP uses UDP as transmission communication protocol, UDP communication message
transmission is not stable, it is necessary to confirm delivery and resent in application.
Generally, when controller sends a command to peripheral equipment, controller will wait for the return
message then send the next command, we can detect and confirm if the peripheral equipment receive the
commands from return message’s lag time. If controller shows it is overtime, it is regarded as error transmission.
If controller shows it is overtime, resend the commands to check peripheral’s status, resent command
sequence number is same as last command, the following chart list the received message and status after resending
the commands.
Lost message Recelved message
for retransmission
Status after
retransmission
Correspondence after retransmission
Command ACK message Command is performed by
retransmission.
Continue processing.
Completion message
For the command
ERROR(Abnormality in the
sequence number.)
Command has been
performed.
If only the ACK message is
lost, the completion message
returns.
If the result by the completion message is needed,
retransmit by updating the sequence number.
Completion message
for the command
ERROR(Abnormality in the
sequence number.)
Command has been
performed.
If the result by the completion message is needed,
retransmit by updating the sequence number.
Inquiry Reply message Inquiry is performed by
retransmission.
Continue processing.
Reply message for the
inquiry
ERROR(Abnormality in the
sequence number.)
Inquiry has been performed. If the result by the reply message is needed, retransmit
by updating the sequence number.
Error message Error message Command is not performed.
If the error cause eliminates,
normal reply is return(ACK,
reply message)
Eliminate the error cause. If normal reply returns,
continue processing.
Inquiry of the VISCA
device setting
command
Reply message of the
VISCA device setting
command
Inquiry has been performed
by retransmission.
Continue processing.
Reply message of the
VISCA device setting
command
ERROR(Abnormality in the
sequence number.)
Inquiry has been performed. If the result by the reply message is needed, retransmit
by updating the sequence number.