DAD 141.1 Technical Manual, Rev. 2.5 – April 2015
Page 44 of 54
10.9. Logic Output Commands - IO, OM, S
’n’, H’n’, P’n’, A’n’, HT
The definitions for this section may be changed due to the fact that the definitions of the logic outputs for the
DAD 141.1, where the status depends on the weight value (setpoint) are to be defined. Each logic output can
be assigned an independent setpoint value (S
’n’) with a corresponding hysteresis/polarity action (H’n’, P’n’) and
allocation (A
’n’ – switch on the gross, net, peak, average etc. weight).
10.9.1. IO
Read / Modify the Status of the logic Outputs
[
Index 0x210A
]
This command reads and can modify the status of the logic outputs (if enabled by the
OM
command). The
status response is in the form of a four digit code where 0 = false and 1 = true (outputs are normally open,
open drain MOSFETs), the least significant bit corresponding to Output 0 etc.
Master (PC / SPS) sends
Slave (DAD 141.1) responds
Meaning
IO
IO:0001
Output 0 is high
IO
IO:0101
Outputs 0 and 2 are high
IO
IO:0111
Outputs 0, 1 and 2 are high
The status of the outputs can be changed by issuing the IO command with the appropriate 4 digit code e.g.
IO 0001 where in this example output 0 will be activated (FET conducting). Please note that the status of the
logic outputs is normally determined by the internal setpoints (see section 10.9.2) and therefore setting the
logic output status using the IO commands is
not
allowed.
Setting
Master (PC / SPS) sends
Slave (DAD 141.1) responds
Meaning
IO_010
OK
Setup output 1 is high
IO_011
OK
Setup outputs 0 and 1 are high
IO_111
OK
Setup outputs 0, 1 and 2 are high
However, the OM command can be used to allow the status of the logic outputs to be set via the IO
command or set their status directly by the host application.
Factory default
: IO=0000
10.9.2. OM Control of the logic outputs by the host application
[
Index 0x2116
]
The logic outputs can be controlled by the host application (as opposed to the normal internal setpoints) if
they are enabled by the OM command and the appropriate 4 digit code.
Master (PC / SPS) sends
Slave (DAD 141.1) responds
Meaning
OM
OM:0001
Enable Output 0
OM
OM:0101
Enable Outputs 0 and 2
OM
OM:0111
Enable Outputs 0, 1 and 2
A “1” bit in the code enables the corresponding logic output to be controlled by the host application using
the IO command. A “0” in the code leaves the corresponding logic output controlled by the internal setpoint.
Logic output 0 is again the least significant bit.
Setting
Master (PC / SPS) sends
Slave (DAD 141.1) responds
Meaning
OM_010
OK
Enables output 1
OM_ 011
OK
Enables outputs 0 and 1
OM_111
OK
Enables outputs 0, 1 and 2
Note:
When reading the status of the logic outputs using the IO command, the setpoint status will be
returned regardless of the OM setting. Sending OM_0000 disables the external logic output control.
Factory default
: OM=0000
