Interrupt support – Zilog Z8F0130 User Manual
Page 226
Using the ANSI C-Compiler
UM013037-1212
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Zilog Developer Studio II – Z8 Encore!
User Manual
return 1;
return ( k * recursive_fn (k-1));
}
When the static call frame option is selected, all call frames are assumed static by the com-
piler unless the
reentrant
storage class is used in the function declaration. Obviously, if
large numbers of functions in an application must be declared reentrant, the benefit of
using static frames diminishes proportionately.
When the dynamic call frame option is selected, all call frames are assumed reentrant by
the compiler.
Interrupt Support
To support interrupts, the Z8 Encore! C-Compiler provides the following features:
•
•
interrupt Keyword
Functions that are preceded by
#pragma interrupt
or are associated with the interrupt
storage class are designated as interrupt handlers. These functions should neither take
parameters nor return a value. The compiler stores the machine state at the beginning of
these functions and restores the machine state at the end of these functions. Also, the com-
piler uses the
iret
instruction to return from these functions.
For example:
void interrupt isr_timer0(void)
{
}
or
#pragma interrupt
void isr_timer0(void)
{
}
Interrupt Vector Setup
The compiler provides two mechanisms for interrupt vector setup:
•
•