PCC-IV Instruction Manual (rev. 0.2)
Page 5-4
Section 5 – Configuring Blockware
PCC-IV Terminology / Glossary
Block
The memory of the PCC-IV is divided into 256 groups. Each group or block can be set-up by the user to perform a
specific task, such as: (A*B), (A+B), square root, PID control, etc. The task that a block performs is determined by
the function type that we assign to the block. Function type is explained below. NOTE: blocks are often referred to
as “B1”, “BLK 1”, or simply by the block’s number.
All blocks are identified by a number (0 thru 255). This number determines the sequence in which the blocks are
executed. Every 100ms (i.e., 10 times/sec), the PCC-IV computes each block in sequence from 0 thru 255, and
updates all Tags.
Blockware Configuration
This refers to the process of entering information into the blocks; such as: the function type (i.e., the task that each
block will perform), the specification of which of the field wiring inputs a block should use, the gain of a PID control
function, etc.… A controller’s configuration determines how the overall controller will function. Multiple PCC-IVs can
be equipped with identical hardware (circuit boards, etc.), but each can be configured to function differently.
Function Type or Function Code Number
The Function Code Number is a number that identifies the type of computation or the type of action that a block will
perform. Examples are:
F2
get an analog Input from the field terminal strip
F51
calculate (A*B) / C
F71
calculate a PID controller Output
F118
x seconds after Input turns on, turn on Output
Numbers are hard to remember, so normally we refer to each of the functions by using an abbreviation (or Function
Name), such as:
F2
AIN
A
nalog
IN
put
F51
AB/C
(
A
*
B
) /
C
F71
PID
PID
controller
F118
DAETDR
D
elay
A
fter
E
nergize
T
ime
D
elay
R
elay
All the functions available in the PCC-IV are listed in numerical order in Section 6 (Blockware Technical Reference)
of the instruction manual, and the task that each type performs is described in detail. Section 6 provides two Table
of Contents: the first is in Function Code Number (numerical) order, the second is in Function Name (alphabetical)
order.
Input
There are two types of inputs: electrical signals that are physically wired to the rear terminal strip of the controller
and imaginary connections inside the PCC-IV that softwire a signal from the output of one block to the input of
another block. Typically, when we talk about inputs we will be talking about the softwire connections internal to the
PCC-IV.
Every block produces at least one output; some functions have multiple outputs. The function type determines the
output value. Some functions do not require any input from any other blocks… for example: the AIN block receives
it’s 0-5 Vdc input from the PCC-IV’s field terminal strip… while other functions require multiple inputs… for example:
the AB/C block requires that three values be inputted (A, B, & C).
Inputs can be referred to by a meaningful abbreviation such as “A”, or “PV” (
P
rocess
V
ariable), or by an Input
number (I1, I2, etc.). Section 6 describes the purpose of each input for each function type. Note: The input value
for one block is always the output value of some other block.
Parameter
Many functions require setup information to work properly; we call these values parameters. A parameter can be
used to make a selection such as: do you want to take the square root of this field? 1 = yes, 0 = no. The reset rate
of a PID function would be considered a parameter. The setpoint of a high alarm would be a parameter.
