User manual
IEC61131 User and Reference Manual 
April 22, 2008     
305 
Outputs 
Type 
Description 
status 
Integer 
This output contains the status of the HART command 
sent to the HART device. 
0 =HART interface module is not communicating 
1 =Command ready to send to device 
2 =Command sent to device 
3 =Response received 
4 =No valid response received after all attempts made 
5 =HART interface is not ready to transmit 
code 
Integer 
This output contains one of the following depending on 
the command status. 
  The number of the current command attempt, or, 
  Zero if the hart device does not respond after all 
command attempts, or, 
  The response code from the HART device to the 
command sent. See the Response Code section 
below for information on response codes. 
v1Current 
Float 
primary variable current 
u1Current 
Integer 
primary variable current units code 
v1 
Float 
primary variable value 
u1 
Integer 
primary variable units code 
v2 
Float 
secondary variable value 
u2 
Integer 
secondary variable units code 
v3 
Float 
tertiary variable value 
u3 
Integer 
tertiary variable units code 
v4 
Float 
fourth variable value  
u4 
Integer 
fourth variable units code 
See Also 
hart1, hart2, hart33 
HART Device Response Codes 
The code output of the function block contains the response code from the HART device 
contains communication error and status information. The information varies by device, but 
there are some common values. 
If bit 7 of the high byte is set, the high byte contains a communication error summary. This 
field is bit-mapped. The following table shows the meaning of each bit as defined by the 
HART protocol specifications. Consult the documentation for the HART device for more 
information. 
Bit 
Description 
6 
vertical parity error 
5 
overrun error 
4 
framing error 
3 
longitudinal parity error 
2 
reserved – always 0 










