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6. RS-485
6-4. Transmission protocols (TD Format/TD Format (BCC))
TD Format does not use checksums.
TD Format (BCC) adds checksums after data.
6-4-1. Commands
TD Format
HEX 0x23 0×30 0×31 0x33 0x30 0×30 0×32 0x2D 0x30 0×31 0×38 0×30 0×30 0×0D
ASCII
#
0
1
3
0
0
2
−
0
1
8
0
0
CR
ID number
Command No.
Data
TD Format (BCC)
HEX 0x23 0×30 0×31 0x33 0x30 0×30 0×32 0x2D 0x30 0×31 0×38 0×30 0×30 0×34 0x43 0x0D
ASCII
#
0
1
3
0
0
2
−
0
1
8
0
0
4
C
CR
ID number
Command No.
Data
Checksum
The first character in the command must always be “#”.
The final characters must be “CR”.
The data length will be 0 to 6 characters according to the command.
The checksum (BCC) adds each byte of the ID number, command and data and divides the lower 8 bits into upper and lower parts of
4 bits each and saves them in ASCII as the checksum.
In the example above, the total of the ID number, command and data is as follows.
0x30+0x31+0x33+0x30+0x30+0x32+0x2D+0x30+0x31+0x38+0x30+0x30
= 0x24C
The checksum is the lower 8 bits, which is 0x4C.
