Chapter 3
Ada Language Reference
3-12
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Calling UCBs
Every one of the following arguments will be passed for each call to the
UCB in the following order:
INFO, T, U, NU, X, XD, NX, Y, NY, R_P, I_P
Within the UCB, the elements of all the array variables (
U
,
X
,
XD
,
Y
,
R_P
,
I_P
) must be accessed as in the following example:
U(U'first), U(U'first+1), ... U(U'first+NU-1)
X(X'first), X(X'first+1), ... X(X'first+NX-1)
Make sure to access the elements in the above manner as all the arrays are
passed as array slices. The sizes of
R_P
and
I_P
must be entered in the
UCB block form to ensure that proper storage is allocated in the caller.
Also, the initial conditions for states have to be specified in the form.
Table 3-5 lists the type and purpose of UCB arguments used in the fixed
calling method.
Table 3-5.
UCB Calling Arguments and Data Types
Argument
Data Type
Description
INFO:in out
RT_STATUS_RECORD
A structure representing operation requests and
status.
T:in
RT_DURATION
Elapsed time.
U:in
RT_REAL_ARRAY
An array (of size NU) of inputs to the UCB.
NU:in
RT_INTEGER
The number of inputs to the UCB.
X:in out
RT_REAL_ARRAY
An array (of size NX) of state variables of the UCB.
XD:in out
RT_REAL_ARRAY
An array (of size NX). Defines the next discrete
states of X for discrete subsystems, and the derivative
of X for the continuous subsystems.
NX:in
RT_INTEGER
The number of states (and next states).
Y:in out
RT_REAL_ARRAY
An array (of size NX). Defines the next discrete
states of X for discrete subsystems, and the derivative
of X for the continuous subsystems.
NY:in
RT_REAL_ARRAY
The number of outputs from the UCB.
R_P:in out
RT_REAL_ARRAY
An array of real parameters.
NRP:in out
RT_INTEGER
The number of real parameters.