ZBasic Language Reference
128
ZBasic Microcontrollers
A third method of guaranteeing atomicity is to explicitly disable and re-enable interrupts as depicted
below.
Dim i as Integer
Sub Main()
Register.SREG = &H00
i = 200
Register.SREG = &H80
End Sub
Although this technique may be useful in rare cases, its use is strongly discouraged. The primary
problem with this method is that it unconditionally re-enables interrupts without regard to whether or not
interrupts were enabled beforehand. A related technique using inline assembly language code, having
the same disadvantage, is shown below.
Dim i as Integer
Sub Main()
#asm
cli
#endasm
i = 200
#asm
sei
#endasm
End Sub
6.5 Attributes for Procedures and Variables
This section describes several special attributes that you can apply to variables or procedures with native
mode devices to obtain special effects. To apply special attributes, you list the desired attributes (see the
table below) in a comma-separated list enclosed in parentheses following the keyword Attribute. This
entire construction is placed at the end of a normal variable, subroutine or function definition as illustrated
in the example below.
Special Attributes
Attribute
Valid For
Description
Inline
subroutine
function
Instructs the compiler to “inline” the code for the
subroutine/function instead of generating a call. Generally, this
yields faster execution, sometimes at the expense of larger
program size.
NoInline
subroutine
function
Instructs the compiler not to “inline” the code for the
subroutine/function and, instead, generate a call to the subroutine
or function.
Used
subroutine
function
variable
Instructs the compiler to include the variable or procedure in the
executable even if it appears not to be used. This is useful, for
example if external C or assembly code needs to use a ZBasic
data item or procedure but it is not otherwise used in the program.
"Alias:name"
subroutine
function
Instructs the compiler to create an alias for the procedure having
the specified name. This is useful on native mode devices to
allow external code to refer to a ZBasic procedure by a pre-
determined name.
Static
variable
Instructs the compiler allocate space for the variable statically.
This attribute is redundant for variables defined at the module
level since that is the default for those. In contrast, variabled
defined within a procedure are normally dynamically allocated, i.e.
they exist only while the procedure is executing.
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