Alcorn Mcbride Digital Video Machine 4, User Manual

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Ethernet Control 31
UDP Message Layer
The control source sends UDP Packets to the DVM4. A UDP Packet contains
information about the packet source (IP Address, Port number) as well as
definable user data. The user data contains the entire DVM4 Control Message
including all AMINet specific bytes. These packets should be sent to the
broadcast IP Address (0xFFFFFF) or the specific DVM4 address with UDP port
number 2639.
Control Message Response
The unit will normally send back a response to each Control Message it
receives. The user data in these responses exactly match those in the Pioneer /
AMI control command descriptions. For example, you’ll receive an “R”
contained when you send a “PL” contained in the AMINet wrapper. The
responses are sent to the IP Address and UDP Port number found in the UDP
packet that contained the original Control Message. As with the Addressable
serial protocol, any Control Message sent to the wildcard unit ID (127) will not
receive any response. This practice avoids any potential confusion at the source
of the Control Message due to many responses to the same message.
A Software Developer’s Kit with C Source Code implementing this protocol is
available on our website at
http://www.alcorn.com/support .