National Instruments AutoCode NI MATRIX - Manual (Page 27)

Chapter 2 C Language Reference
AutoCode Reference 2-10 ni.com
External_Input ( ) Function
RT_INTEGER External_Input(void)
External_Input( ) is for use in the simulation comparison mode; it
reads in external input data from your specified FSAVE input file. The data
appears in XINPUT , an array of type RT_FLOAT , dimensioned equal to the
input vector ( T - and U -vectors) defined at simulation time. No data
conversion is required in this version of the generated code, because all data
is passed as arrays of type
RT_FLOAT . The routine returns the value of
SCHEDULER_STATUS , which reports on the success of the input operation
and is passed to the External_Input( ) routine by the scheduler. In the
target version of sa_utils.c , the operation of this function is much the
same; every time it is called, External_Input( ) returns an input vector
from the hardware sensors.
External_Output ( ) Function
RT_INTEGER External_Output(void)
External_Output( ) is for use in the simulation comparison mode;
it posts external output data to your specified output file. The data is
presented in
XOUTPUT , an array of type RT_FLOAT , dimensioned equal to
the output Y vector as defined at simulation time. No data conversion is
required in this version of the generated code, because all data is passed
as arrays of type
RT_FLOAT . The routine returns the value of
SCHEDULER_STATUS , which is passed to it by the scheduler. In the target
version of sa_utils.c , the operation of this function is much the same;
every time it is called, External_Output( ) posts an output vector to the
software data bus.
UserCode Blocks
This section describes how to link UserCode Blocks (UCBs) with
AutoCode or SystemBuild applications. AutoCode supports all
SystemBuild data types for inputs and outputs and the generation of the
fixed and variable interface options. The variable interface does not include
optional arguments to the user code—for example, states—if that argument
is not specified in the UCB. Unless otherwise stated, the following sections
describe the fixed interface option of a UCB.