Philips BDS4621-27 - Manual (Page 51)

Packet Type
The Packet Type (ePacketType) is a BYTE in length
number that defines the type of data in the packet.
The following entries are valid packet typess:
Packet Type Name Packet Type Number Description
pt_INVALID 0 Invalid Packet Type
RESERVED 1 RESERVED
pt_EVENT 2 Host can send any event defined in
Philips PDP software.
pt_OPERATION 3 Host can send any operation defined in
Philips PDP software.
Table 6: Packet Types
Packet Payload Size
The Packet Payload Size (nPacketSize) is a BYTE
that defines the size of the Payload portion of
the packet. If the packet contains only header
information, this is zero.Therefore, the total byte
count of any packet = nPacketSize plus 7 (since
the Packet Header is seven bytes long).
Packet Checksum (CRC)
Each packet is CRC’ed using the tables later in
this document.This number is the CRC value for
the complete packet including the Packet Header
and Packet Payload.The CRC is calculated with
the nCRCPacket value initialized to zero.
1.1.3. Packet Payload Definition
Event Packet Type
The Event packet is used by the host system to
send virtual events (such as Zoom, Source, Auto
Adjust, etc.) to the target system. Packet payload
size is 6 bytes.
Byte Field Name Field Value Description
0-1 Virtual Event Virtual Event ID as defined through Configurator
2-5 Parameter Parameter that can be associated with the event.
Table 7: Event Packet Type Format
The source code definition of the Message
packet data structure is:
typedef struct
{
WORD eEvent;
DWORD dwParam;
} EVENT_MESSAGE;
This lets you send any event defined in
Configurator to the system including all remote,
IR, or special events.
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User Manual BDS4621
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