Rockwell Automation 2755-SNx Adaptascan Bar Code Readers - Manual (Page 73)

4–17 Downloading Match Codes via DH485 Protocol with an SLC 5/03
t
or SLC 5/04
t
Controller
Publication 2755-6.8
To download match codes from the SLC you must:
1. Convert the match string to hex.
2. Enter the match string in the proper data packet format (byte
swapped).
3. Send the data packet (containing the string) to the reader.
Convert the Bar Code String to Hex
Convert the bar code string you want to send to the reader to the
hexadecimal ASCII equivalent value. For example:
0 3 0 0
30 33 30 30
Bar Code String:
Converted Hex Value:
0 4 0 0 Converted Bar Code Length Value:
In the bar code length value shown above, if the number of
characters 04 were changed to 14, the hexadecimal value would be
0E. This hexadecimal value is written as 0E00.
Place the String in the Data Packet
The bar code string is sent in a data packet having this format:
3F 10 CE 01 00 03 04 00 30 33 30 30
Bar Code String # of Characters
in Bar Code
String
Instance
Number
The following are descriptions of the data packet:
3F = DeviceNet Address (3F= 63, each reader has unique address)
10 = Set attribute (single request)
CE = 206 = Class (always 206 for match table)
01 = Instance Number (LSB)
00 = Instance Number (MSB)
03 = Attribute Number – Rule
04 = Length of String (LSB)
00 = Length of String (MSB)
30 = ASCII “0”
33 = ASCII “3”
30 = ASCII “0”
30 = ASCII “0”
Note: You can use the Windows calculator to convert decimal
values to hexadecimal.
Downloading Match Codes