IX34208a_e.doc / Aug-09
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4.4.1.
PC-Mode
Communication with PC - Mode allows free readout of all parameters and registers of the unit.
The subsequent example shows the details of communication for serial readout of the actual
display value.
The general string to initiate a request has
the following format:
EOT
AD1
AD2
C1 C2 ENQ
EOT = Control Character (Hex 04)
AD1 = Unit Address, High Byte
AD2 = Unit Address, Low Byte
C1 = Register Code, High Byte
C2 = Register Code, Low Byte
ENQ = Control Character (Hex 05)
Example:
Request string for readout of the actual display data from a unit with serial address No. 11:
ASCII-Code:
EOT 1 1 : 1 ENQ
Hex:
04 31 31 3A 31 05
Binary:
0000 0100 0011 0001
0011 0001
0011 1010
0011 0001
0000 0101
With a correct request the unit will
respond with the adjoining response
string. Leading zeros will be suppressed.
BCC provides a „Block Check Character“,
formed by Exclusive-OR of all characters
from C1 through ETX.
STX C1 C2 x x x x x x x ETX BCC
STX = Control Character (Hex 02)
C1 = Register Code, High Byte
C2 = Register Code, Low Byte
x x x x x = Data (display value)
ETX = Control Character (Hex 03)
BCC = Block Check Character
With inaccurate request strings the unit would only respond "STX C1 C2 EOT" or just "NAK".
