Reference Manual

00809-0100-4697, Rev EA October 2011

BLOCK CONFIGURATION

Rosemount 848T

Resource Block

The resource block defines the physical resources of the device including type of measurement, memory, etc. The resource block also defines functionality, such as shed times, that is common across multiple blocks. The block has no linkable inputs or outputs and it performs memory-level diagnostics.

Table 3-2. Resource Block Parameters

Number

Parameter

Description

01

ST_REV

The revision level of the static data associated with the function block.

02

TAG_DESC

The user description of the intended application of the block.

03

STRATEGY

The strategy field can be used to identify grouping of blocks.

04

ALERT_KEY

The identification number of the plant unit.

05

MODE_BLK

The actual, target, permitted, and normal modes of the block. For further description, see the

 

 

Mode parameter formal model in FF-890.

06

BLOCK_ERR

This parameter reflects the error status associated with the hardware or software components

 

 

associated with a block. Multiple errors may be shown. For a list of enumeration values, see

 

 

FF-890, Block_Err formal model.

07

RS_STATE

State of the function block application state machine. For a list of enumeration values, see

 

 

FF-890.

08

TEST_RW

Read/write test parameter - used only for conformance testing.

09

DD_RESOURCE

String identifying the tag of the resource which contains the Device Description for the

 

 

resource.

10

MANUFAC_ID

Manufacturer identification number - used by an interface device to locate the DD file for the

 

 

resource.

11

DEV_TYPE

Manufacturer's model number associated with the resource - used by interface devices to

 

 

locate the DD file for the resource.

12

DEV_REV

Manufacturer revision number associated with the resource - used by an interface device to

 

 

locate the DD file for the resource.

13

DD_REV

Revision of the DD associated with the resource - used by the interface device to locate the

 

 

DD file for the resource.

14

GRANT_DENY

Options for controlling access of host computer and local control panels to operating, tuning

 

 

and alarm parameters of the block.

15

HARD_TYPES

The types of hardware available as channel numbers. The supported hardware type is:

 

 

SCALAR_INPUT

16

RESTART

Allows a manual restart to be initiated.

17

FEATURES

Used to show supported resource block options. The supported features are: Unicode,

 

 

Reports, Soft_Write_Lock, Hard_Write_Lock, and Multi-Bit Alarms.

18

FEATURE_SEL

Used to select resource block options.

19

CYCLE_TYPE

Identifies the block execution methods available for this resource. The supported cycle types

 

 

are: SCHEDULED, and COMPLETION_OF_BLOCK_EXECUTION

20

CYCLE_SEL

Used to select the block execution method for this resource.

21

MIN_CYCLE_T

Time duration of the shortest cycle interval of which the resource is capable.

22

MEMORY_SIZE

Available configuration memory in the empty resource. To be checked before attempting a

 

 

download.

23

NV_CYCLE_T

Minimum time interval specified by the manufacturer for writing copies of NV parameters to

 

 

non-volatile memory. Zero means it will never be automatically copied. At the end of

 

 

NV_CYCLE_T, only those parameters which have changed need to be updated in NVRAM.

24

FREE_SPACE

Percent of memory available for further configuration. Zero in preconfigured resource.

25

FREE_TIME

Percent of the block processing time that is free to process additional blocks.

26

SHED_RCAS

Time duration at which to give up on computer writes to function block RCas locations. Shed

 

 

from RCas will never happen when SHED_RCAS = 0.

27

SHED_ROUT

Time duration at which to give up on computer writes to function block ROut locations. Shed

 

 

from ROut will never happen when SHED_ROUT = 0.

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Emerson 848T manual Block Configuration, Resource Block, Number Parameter Description

848T specifications

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