Alcorn Mcbride Digital Video Machine HD, Руководство пользователя

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Ethernet Control 51
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0x01 + 0x04 + 0x35 + 0x35 + 0x40 + 0x52 + 0x4A + 0x0D = 0x158.
The Checksum in this example is 0x158, but because it is greater than 0xF9, the
two byte Checksum is preceded by 0xFF.
UDP Message Layer
The control source sends UDP Packets to the Information Station. 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 UDP Control
Message including all AMINet specific bytes. These packets should be sent to
the broadcast IP Address (255.255.255.255) or the unit’ s IP address (if you need
to control one particular unit a network of many) with UDP port number 2639.
Control Message Response
The Information Station 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 Serial control command descriptions but will have the added
AMINet wrapper like a Control Message. For example, you’ ll receive an “ R”
contained in the AMINet wrapper 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.