Pepper Computer Modular Computers RS485 - Manual (Page 155)

Digital Modules
08 Jan. 98
SMART I/O User’s Manual
Page 4 - 69 Manual ID 09901, Rev. Index 0500
Logical Address
The 8 inputs of this module may be clearly seen together with
the logical address at which this particular board is residing.
Remember, this logical address is the same as the physical slot
position! In the example shown here, the board being addressed
is in slot 2 i.e. the second of the SMART-BASE slots. Up to 11
slots are catered for in the SMART I/O concept; 3 on the
SMART-BASE and 2 for each connected SMART-EXT (up to a
total of 4).
4.4.9.2 ISaGRAF Operate Calls
Operate calls are built into a program using ST or FBD lan-
guages when defining the project. A typical use could be at the
initialization stage to check that the SMART-Modules are in fact
located where they have been programmed to be. The syntax of
the operate call is as follows:
Syntax
<return variable> := OPERATE(<source var>,
COMMAND,<source data>);
Here the return variable is assigned a value associated with the
selected COMMAND parameter. Each SMART-Module pos-
sesses its own set of such COMMANDS.
Example
<error.code>:= OPERATE(<channel>,
O_INIT_CODE, 0);
O_INIT_CODE is one of a number of distinct commands recog-
nized by the PEP Modular Computers’ implementation of board
drivers and checks, for example, that the board is located where
the program expects it to be.