FC 41 - Digital Input (Periodic Sample)

In the HAC controller, the digital input (periodic sample) function code acquires digital signals via the Controlway/module bus from other master modules. The input points must be in the same process control unit (PCU) node. The signal is updated at periodic intervals depending on the periodic I/O sampling period that is specified in the segment control block for the Harmony controllers.

 

The HAC controller uses FC 45 to acquire a digital input signal from another HAC controller via the peer-to-peer network. Specification S8 in FC 57 is used to specify the maximum number of destination nodes the HAC controller may communicate with. The signal is updated at periodic intervals depending on the periodic I/O sampling period that isspecified in the segment control block for the Harmony controllers.

 

To insure that the signal is successfully acquired from the source node/module, the digital signal generates a point quality flag. To test the quality of the signal, include a function code 31 in the configuration. The output of the test quality block can be used as an input to other digital processing blocks to provide signal quality information.  Refer to Appendix H, for a definition of point quality.

 

NOTE: A block defined as an analog input reads a value for any existing analog output from a function block configured

in the source node/module. No additional configuration in the source node/module is required.

 

Outputs:

Blk

Type

Description

N

R

Output value and quality. Quality:

0 = good

1 = bad

 

 

Specifications:

Spec

Tune

Default

Type

Range

Description

S1

N

0

I

0 - 31

Requested module address

S2

N

0

I

Note 1

Requested block address

 

NOTES:

1. Maximum values are: 9,998 for the BRC-100, IMMFP11/12 and 31,998 for the HAC

 

41.1  Examples

 

Figure 41-1 and 41-2 illustrates the configuration required to test the point quality from a digital input (periodic sample) function code.