Rockwell Automation 1760 Pico GFX-70 Controllers Quick Start - Manual (Page 37)

Publication 1760-QS002A-EN-P - April 2004
Lesson 4 6-5
This enables the parameter set of the function block to be called
and modified on the device during operation. For this, the
program must have been transferred to the device beforehand.
We have now wired the most important function block in our mini
project and defined its parameters. However, the counter function
block is then not only displayed in the circuit diagram. Unlike Pico
projects, Pico GFX-70 projects also have a function block diagram as
well as the circuit diagram. We can see this via View, Function
Blocks or directly via the
button.
The function block diagram provides the user with an overview of all
the function blocks used in the program as well showing which of the
inputs and outputs of the function block are used where.
We have used counter C01 in our program, set its upper setpoint (SH)
to 16 and buffered the actual value in marker byte 1. We have also
assigned the P1 button to its Count coil so that the function block
knows when to increment its actual value by 1. The counter is shown
in the function block diagram in the following way:
A function block can contain inputs and outputs as well as contacts
and coils. The inputs and outputs of the function block are always
shown in bold type (in this case SH, SL, SV, and QV). The inputs are
located on the left and the output on the right. The function block
inputs read 32-bit values, and the QV output also supplies the actual
value of the function block as a 32-bit value. QV can be saved in a
marker byte (MB), marker word (MW), marker double word (MD) or
passed on directly to the output of the device.
The function block contacts are shown in normal type on the right of
the function block. They can be integrated in the circuit diagram as
contacts. These contacts can also be used to read the states of the
function block and logically link them in the circuit diagram.
Example: In our project, when the counter has reached 16, this sets
function block contact OF (actual value greater than or equal to upper