Pepper Computer Modular Computers RS232 User Manual

SMART I/O User’s Manual

October 01, 1996

©1996 PEP Modular Computers GmbH

Page 5 - 102

Chapter 5  Analog Modules

Operate calls are built into a program using ST or FBD languages 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 pro-

grammed to be. The syntax of the operate call is as follows:

<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 possesses its own set of

these 

COMMANDS

.

<error.code>:= OPERATE(<channel>, O_INIT_CODE, 0);

O_INIT_CODE

 is one of a number of distinct commands recognized 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.

channel

 provides channel specific information and in the example shown

here, any of the 8 input channels may be used. The last parameter is not

usually used by PEP implementations and is set to 0 (zero).

The 

error.code

 returns a value of zero if no error was detected, other-

wise it returns a non-zero value depending on the error encountered. A list of

these error codes may be found in the PEP online help.