Siemens SIMATIC TIWAY 1 - Manual (Page 202)

USING THE BDLC PROTOCOL
UNILINK HOST ADAPTER B–17
USER MANUAL
Example B–3 Block Checksum Transmitter Calculation
DLE–STX Address Control Information BCS DLE–ETX
1002 01 93 1003
“SNRM”
(Note: All values are in hexadecimal notation.)
BCS
0 1 2 3 4 5 6 7 8 9 10 12 13 14 15
MSB LSB
Bit
Frame
Byte BCS
MSB BCS
LSB
01
00
01 00
01
93 94
2A 95
95
Complement
the MSB
The BCS is then D595
D5