FC 185 - Digital Input Subscriber

The digital input subscriber acquires a group of digital values from a factory instrumentation protocol (FIP) device. Each digital input subscriber can handle up to eight digital inputs. Up to four digital input subscribers may be linked together allowing one FIP identifier to reference up to 32 inputs. Link all FIP identifiers configured as digital input subscribers together. Each block specifies the next block address in the link.

 

The digital input subscriber has eight outputs corresponding to the eight digital values acquired with quality.

 

NOTES:

  1. For more information on factory instrumentation protocol, refer to the FIP Application Description C46-602 which is written by the French Commission AFNOR, and the INFBA01 Programming Reference Manual.

  2. If configuring function code 185 for an Ethernet device interface slave (IMEDI01), refer to the IMEDI01 instruction for details of this function code.

 

 

 

 

Outputs:

Blk

Type

Description

N

B

First digital input with quality

N+1

B

Second digital input with quality

N+2

B

Third digital input with quality

N+3

B

Fourth digital input with quality

N+4

B

Fifth digital input with quality

N+5

B

Sixth digital input with quality

N+6

B

Seventh digital input with quality

N+7

B

Eighth digital input with quality

 

 

 

Specifications:

Spec

Tune

Default

Type

Range

Description

S1

N

2

I

Note 1

Block address of next digital input subscriber block

S2

N

0.000

R

0 - 60000

FIP variable identifier2

S3

N

0

I

01 - 38

Group number (X) and number of elements (Y):

 

X = 0, 1, 2 or 3

Y = 1 through 8

 

X

Y

Total

0

1 - 8

8

1

1 - 8

16

2

1 - 8

24

3

1 - 8

32

 

S4

N

0

I

0 - 3

Input type:

0 = digital

1 = digital with check

2 = boolean

3 = boolean with check

S5

N

0.000

R

Full

Asynchronous promptitude period in msecs3

S6

N

0.000

R

Full

Synchronous promptitude period in msecs3

S7

N

00

I

0 or 1

Aperiodic and periodic variable:

0 = aperiodic variable

1 = periodic variable

 

S8

N

00

I

00, 01, 10 or 11

Asynchronous and synchronous refresh

evaluation:

00 = asynchronous and synchronous refresh disabled

01 = synchronous refresh enabled

10 = asynchronous refresh enabled

11 = partial refresh (asynchronous refresh and synchronous refresh enabled)

 

S9

Y

0.000

R

Full

Spare

S10

Y

0.000

R

Full

Spare

S11

Y

0.000

R

Full

Spare

 

NOTES:

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

  2. Refer to S2 under Specifications for additional information.

  3. For most applications, the default value shown will suffice for the specification.

 

 

 

185.1   Explanation

 

185.1.1  Specifications

 

S1

Block address of the next digital input subscriber block.

 

S2

FIP variable identifier. All data transfer function codes refer to a FIP variable identifier. This is a 16-bit value (unsigned

integer) and defines the variable (read or written from the controller module) for the application layer of the FIP identifier

implemented in the I/O module.

For most WorldFIP applications, FIP variable identifiers are shown in a hexadecimal format. Refer to the following example

of converting hexadecimal values to decimal values.

 

Example:

A hex number can be expressed as:

 

(H0 x 1) + (H1 x 16) + (H2 x 162) + (H3 x 163) ... etc.

 

where H0 is the least significant hex digit and H1 is the next significant, and so on.

 

Example:

 

If the variable identifier was 3AE0, to convert the hex number 3AE0 to decimal:

 

The least significant hex digit is 0. The next digit is E or 14. The next digit is A or 10. The next digit is 3 or 3. Referring to the preceding equation, the decimal number is:

 

(0 x 160) + (14 x 161) + (10 x 162) + (3 x 163)  =  0 x 224 + 2560 x 12288  =  15072

 

 

S3

Input group. Digital input secondary module subscribers handle up to four groups of eight inputs. The input group is identified as shown in Table 185-1.

 

 

 

 

S4

Function type.

0 = digital

1 = digital with check

2 = boolean

3 = boolean with check

 

NOTE: Refer to FIP Variable Input/Output Types in function code 184 for the format of each of these function types.

 

S5

Asynchronous promptitude period. The asynchronous promptitude period is used to measure how promptly the FIP variable is being updated by the field bus relative to the last time that is was updated. The asynchronous promptitude evaluation is disabled if this specification is zero.

 

S6

Synchronous promptitude period. The synchronous promptitude period is similar to the asynchronous promptitude period. The difference between the two is that the synchronous promptitude is used to measure how promptly the FIP variable is being updated relative to a synchronization variable produced on the field bus. (Refer to S10 of function code 184 .) The synchronous promptitude evaluation is disabled if this specification is zero.

 

S7

Periodic and aperiodic variable setting. Periodic variables are produced and consumed on a periodic basis by devices on the field bus. Periodic variables are typically used for process values that are updated regularly, for example, temperature and pressure values.

 

Aperiodic variables are produced and consumed on the field bus only when requested by either the producer or a consumer of the variable. Aperiodic variables are typically used for status and alarm information, or in some cases, infrequently sampled process data such as chromatograph and pH meter readings. The use of aperiodic variables instead of periodic variables, where appropriate, allows for a more efficient use of the field bus.

 

Function code 185 always reads the latest consumed values regardless of this setting. However, this specification must be set appropriately for the FIP I/O module to treat the variable as either periodic or aperiodic.

 

S8

Refresh evaluation setting. The refresh evaluation setting determines how the FIP I/O module is to interpret the refresh status flag contained with the FIP variable that is being consumed.

 

Refer to S16 of function code 188 for definitions of asynchronous refreshment, synchronous refreshment and partial

refreshment.

 

The FIP I/O module will not consume FIP variables with bad refresh status.

 

 

 

185.2   Applications

 

Refer to function code 184 for an example and application of FIP function codes 184 through 188.