Philips BDS4621 user manual Send Command Introduction, Byte

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User Manual BDS4621

1.2. Send Command

1.1.2. Introduction

Command packets consist of "Header" and "Payload". The Packet Header is consistent for all packets. The Packet Payload type and content varies based on the type of packet sent. The entire packet size is variable, being the sum of the fixed-size Packet Header and variable-sized Packet Payload.

Packet Header (fixed size)

Packet Payload (variable size)

Table 4

Packet Header Format

Introduction

All Packets use the same Packet Header format illustrated in Table 5.

Byte 0

1

2

3

 

 

4

 

5

 

6

 

 

Magic Number

 

Type

Packet Payload Size

 

 

CRC

 

 

0xBE

0xEF

type

size_lo

 

size_hi

 

crc_lo

 

crc_hi

 

 

 

 

Table 5

 

 

 

 

 

 

 

 

 

 

 

 

The Packet Header size is fixed at seven bytes

 

 

 

(Intel byte ordering is used). The following code

 

 

 

fragments are taken from these source files

 

 

 

The Packet Header definition is shown below:

 

 

 

typedef

struct

 

 

 

 

 

 

 

 

{

 

 

 

 

 

 

 

 

 

 

 

 

 

BYTE

ePacketType;//type

of

the

 

 

 

 

payload

 

 

 

 

 

 

 

 

 

WORD

nPacketSize;//size

of

the

 

 

 

 

payload

 

 

 

 

 

 

 

 

 

WORD

nCRCPacket;//CRC for

the

 

 

 

 

entire packet

 

 

 

 

 

 

 

} PACKET_HEADER;

 

 

 

 

Magic Number

The Magic Number is a fixed value that is used to insure packet alignment if there are partial packets received or bytes lost.

The Magic Number is a WORD in length (2 bytes). The Magic Number value is 0xEFBE. Because Intel byte ordering is used, the ls-byte of the word is sent first (byte0 = 0xBE), then the ms-byte (byte1 = 0xEF).

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Contents Philips Business Solutions Table of Contents Important Safety Instructions Read before operating equipmentPage Know These Safety Symbols U T I O NCleaning & Care END-OF-LIFE DisposalUnpacking InstallationBefore USE Product Features Package Contents Names and Functions of Parts SideviewInput Remote control windowFront View MenuLeft/right arrow buttons STANDBY/ONRear View CbPb/CrPr AudioVideo Remote Control TV Channel Selection DisplayVideo Use of Remote Control Inserting of Remote Control BatteriesScope of Remote Control Rear view Connection to External EquipmentPC Module PC Module + Video Module Connection to External Speakers Display standby mode Power ON/OFFSelection of Input Mode Basic OperationPC Module Input Menu with modes Selection of Video Input ModeSelection of PC Input Mode OSD Option Adjustment Exit buttonSound Adjustment Zoom FunctionsOther Functions PC Table PIP Setting TableOSD Functions AV TablePC Display page Screen OSD Pages and FunctionsDisplay Pages Video Display page ScreenImage and AV System AudioPC and Video Language and Screen Saver Advanced ModeLanguage and Screen Saver Misc. PIP Size PIP Settings PC onlyUser Color Temp AV only PIP SourceVideo Status Status? PC Status Speaker Set Optional AccessoriesStand BM05111 Ceiling Mount Kit BM01111 Technical Specifications Video ModuleFactory Settings Cleaning of Screen Cleaning and TroubleshootingCleaning the cabinet and Remote Control Simple TroubleshootingProblemMeasures Check that the Display is not in ‘Mute’ mode What is EXCLUDED? Limited Warranty EURWhat is COVERED? Two Year Free Labor Two Year Free PartsWhere is Service AVAILABLE? Remember Limited Warranty USA OneYear Free Labor One Year Free PartsTo GET Warranty Service Canada Remember Page Appendix Setup Connecting Serial Communication Protocol RS-232Packet Header AckSend Command Introduction ByteByte Field Name Field Value Description Packet Type Number DescriptionPacket Payload Definition Operation Packet Type OperationexecuteSend Command Packet PayloadSerial Communication Cable and Parameters Software Flow Chart Command Packet Header 7 bytes Packet Payload 25 bytes Command ListCommand Packet Header 7 bytes Packet Payload 6 bytes Be EF 03 19 00 43 E8 Be EF 03 19 00 81