10 - sequence block, General, Block description – Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) Algorithms, Tables and Sequential Logic Functions User Manual
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Logic Functions - Book 2
SEQUENCE BLOCK
10-1
SECTION 10
SEQUENCE BLOCK
DATABASE PARAMETERS
10.1 GENERAL
This section includes database reference information for the Sequence Block. For information
on environmental, communications, and I/O block parameters, see IB-23G600. This
reference information includes, block capabilities, a description of block operation, and
attribute descriptions. The information is intended to aid the user in understanding and
configuring the instrument database. Also included is information on database organization
and memory block structures for users developing their own interface software.
All valid attributes are listed in attribute number order in a block data table in Section 10.4.5.
A detailed explanation for each attribute is given in a listing following the table. The attribute
numbers are helpful for locating an attribute description, but are only required for users
developing their own interface. Version attributes exist to support block enhancement and are
explained when required for the blocks affected.
10.2 BLOCK DESCRIPTION
Batch, logic and other types of sequential control are supported through the use of the
sequence block. This block permits the user to configure a series of inputs and outputs, and
sequence the outputs through a series of steps.
Allowable inputs can be either local data of a specified type, or a connection from another
block in the database. For information on data types, see IB-23G600 Section 2.3.4 Data
Types.
Outputs can be either internal data of a specified type, or input from outside the block. The
configured output data type must match that of the input source.
Each configured step allows the user to specify a value for each output for that particular step.
The outputs are set upon entry into each step. Progression through the steps is controlled
either by a signal from an external step source or by step transition expressions (equations)
configured by the user. The expressions are based on if-then-else logic statements that allow
the user to skip steps, specify several steps for various outputs, and go back to previous
steps.