Motorola SE955 Integration Manual page 218

START_DECODE
Description: Tell decoder to attempt to decode a bar code
Packet Format
Length Opcode
0x04 0xE4
Field Descriptions
Field Name
Length Length of message (not including
checksum)
Opcode 0xE4
Message Source 4 = Host
Status Bit 0: Retransmit
Bit 1-7: Unused
Data
Checksum 2's complement sum of message
contents excluding checksum
This command tells the decoder to start a scan and decode session. The decode session ends with a
successful decode, a scan session time-out, or a STOP_DECODE command.
Host Requirements
If the TRIGGER_MODE parameter is set to HOST, the host can use this command instead of a trigger pull.
Decoder Requirements
None.
Message Source
0x04
Format
Simple Serial Interface 10 - 31
Status Data Checksum
Size
1 Byte Length field
1 Byte Identifies this Opcode type
1 Byte Identifies where the message is coming
from
1 Byte Identifies the transmission status
Unused bits must be set to 0
None
2 Bytes Checksum of message
Description