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4-4 DECODE_DATA
Description: Decode data in UART packet format
Packet Format
Length
Opcode Status Decode Data Checksum
0x50
(‘P’)
Field Descriptions
Table 4-6 Field Descriptions
Field Name
Format
Size
Description
Length
Length of message (not
including checksum).
1 Byte
Length Field
Opcode
0x50
1 Byte
Identifies the opcode type.
Status
Bit 0：Retransmit
Bit 1-6：Unused
Bit 7: Command source
1 Byte
Bit 0: Identifies the transmission status.
Bit 7: 1: Command is from the host.
0: Command is from the scanner.
All unused bits must be set to 0.
Decode Data <data>
Variable
The decoded data include prefix, suffix
and so on, which is sent in ASCII format.
Checksum
2's complement sum of
message contents excluding
checksum.
2 Bytes Checksum of message.
The scanner uses this opcode when data packet is selected to send decoded barcode data to the host.
The decoded message is contained in the Decode Data field.
Host Requirements
If ACK/NAK handshaking is enabled, the host responds ACK to the scanner when received correct data
packet.
Scanner Requirements
Decode data is sent in this format if decode data packet is selected via parameter. The host responds to
this message with a CMD_ACK, if ACK/NAK handshaking is enabled.
For example: the decode result is “1234”, the data packet sent to host is as following.
Length
Opcode
Status
Decode Data
Checksum
0x07
0x50
0x00
0x31 0x32 0x33 0x34 0xFE 0xDF
Note: Checksum=0x10000-0x07-0x50-0x00-0x31-0x32-0x33-0x34=0xFEDF.
