LD25x
7.5.1 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.
This is the general format of
a serial request string:
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 for the actual display value from unit number 11.
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
Upon correct request the unit
will respond as shown on the
right. Leading zeros will be
suppressed.
BCC represents a block check
character generated from an
Exclusive-OR of all characters
from C1 through ETX
(inclusively).
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 = Register data
ETX = Control character (Hex 03)
BCC = Block check character
With incorrect request strings, the unit only responds STX C1 C2 EOT or just
NAK.
Provided the actual display value of the unit is "-180" for instance, the full
response of the unit will be as shown below:
ASCII
STX
:
1
-
1
8
0
ETX
BCC
Hex
02
3A
31
2D
31
38
30
03
1C
Binary
0000
0010
0011
1010
0011
0001
0010
1101
0011
0001
0011
1000
0011
0000
0000
0011
0001
1100
Again BCC represents the block check character formed from the Exclusive-OR
of all characters from C1 through ETX.
MAN LD25x E 1.0.odt
Set-up procedure
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