Fm210_01b_oi_e.docx / Nov-20
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Lecom Protocol
If you communicate with the unit by the Lecom protocol, you have full read and write access to all
internal parameters, states and actual values.
The unit uses the Lecom protocol according to DIN ISO 1745. The serial access codes for all
parameters of the unit are specified in the parameter list.
Lecom Read
To request data from the unit, the following request string must be sent:
EOT AD1 AD2 C1 C2 ENQ
EOT = control character (Hex 04)
AD1 = unit address, High Byte
AD2 = unit address, Low Byte
C1 = code, High Byte
C2 = code, Low Byte
ENQ = control character (Hex 05)
If the current differential counter for example should be read (code: 1), with the unit address 11
(parameter RS Unit No.), then the detailed request string is:
ASCII-Code:
EOT
1
1
:
1
ENQ
Hexadecimal:
04
31
31
3A
31
05
Binary:
0000 0100 0011 0001 0011 0001 0011 1010 0011 0001 0000 0101
If the request is correct the answer of the unit is:
STX C1 C2 x x x x x x x ETX BCC
STX = control character (Hex 02)
C1 = code, High Byte
C2 = code, Low Byte
xxxxx =data to be read
ETX = control character (Hex 03)
BCC = block check character
Leading zeros are not transferred. The Block Check Character (BCC) is formed by an EXCLUSIVE-
OR function of all characters from C1 to ETX (each inclusive).
