Delta DVP-ES2 - Manual (Page 408)

D V P - E S 2 / E X 2 / S S 2 / S A2 / S X 2 / S E O p e r a t i o n M a n u a l - P r o g r a m m i n g
3-292
LRC checksum: 01 H + 03 H + 07 H + 08 H + 00 H + 06 H = 19 H. Operate 2’s complement on 19H
and the result is E7H. Store ‘E’(45 H) in the low byte of D113 and ‘7’ (37 H) in the low byte of D114.
Remarks:
ASCII mode communication data:
STX ‘: ’ Start word = ‘: ’ (3AH)
Address Hi ‘ 0 ’
Address Lo ‘ 1 ’
Communication:
8-bit address consists of 2 ASCll codes
Function Hi ‘ 0 ’
Function Lo ‘ 3 ’
Function code:
8-bit function consists of 2 ASCll codes
‘ 2 ’
‘ 1 ’
‘ 0 ’
‘ 2 ’
‘ 0 ’
‘ 0 ’
‘ 0 ’ DATA (n-1)
…….
DATA 0
‘ 2 ’
Data content:
n × 8-bit data consists of 2n ASCll
codes
LRC CHK Hi ‘ D ’
LRC CHK Lo ‘ 7 ’
LRC checksum:
8-bit checksum consists of 2 ASCll codes
END Hi CR
END Lo LF
End word:
END Hi = CR (0DH), END Lo = LF(0AH)
LRC checksum: Operate 2’s complement on the summed up value from communication address
to the end of data, i.e. 01 H + 03 H + 21 H + 02 H + 00 H + 02 H = 29 H, the operation result of 29H
is D7H.