The file <intrrpt.h> is similar to the file <signal.h> but declares macros and functions for interrupt handling rather than signal handling.
The macros defined are:
INT_DFL
INT_ERR
INT_IGN
which expand to constant expressions with distinct values that are type compatible with the second argument to and the return value of the handler function, and whose value compares unequal to the address of any declarable function; and the following, each of which expands to a positive integral constant expression that is the signal number corresponding to the specified condition.
For the M1750 the interrupt numbers are defined as follows:
#define INTPWRDWN 0 #define INTMACHERR 1 #define INTSPARE1 2 #define INTFLVFLOW 3 #define INTFXVFLOW 4 #define INTBEX 5 #define INTFLUFLOW 6 #define INTTIMERA 7 #define INTSPARE2 8 #define INTTIMERB 9 #define INTSPARE3 10 #define INTSPARE4 11 #define INTLEVEL1 12 #define INTSPARE5 13 #define INTLEVEL2 14 #define INTSPARE6 15
For the ERC32 the interrupt numbers are defined as follows:
#define INTMASKED_ERRORS 1 #define INTEXTERNAL_0 2 #define INTEXTERNAL_1 3 #define INTUART_A_RX_TX 4 #define INTUART_B_RX_TX 5 #define INTCORRECTABLE_MEMORY_ERROR 6 #define INTUART_ERROR 7 #define INTDMA_ACCESS_ERROR 8 #define INTDMA_TIMEOUT 9 #define INTEXTERNAL_2 10 #define INTEXTERNAL_3 11 #define INTGENERAL_PURPOSE_TIMER 12 #define INTREAL_TIME_CLOCK 13 #define INTEXTERNAL_4 14 #define INTWATCHDOG_TIMEOUT 15
#include <intrrpt.h>
(*handler (int i, void
(*func)(int)))handler (
int );
The handler function chooses one of three ways in which receipt of the interrupt number i is to subsequently handled. If the value of func is INT_DFL, default handling for that interrupt will occur. If the value of func is INT_IGN, the interrupt will be ignored. Otherwise func shall point to a function to be called when the interrupt occurs. Such a function is called a interrupt handler.
When a interrupt occurs, if func points to a function, first the equivalent of handler(INT,INT_DFL); is executed or an implementation-defined blocking of the interrupt is performed. Next the equivalent of (*func)(i); is executed. The function func may terminate by executing a return statement or by calling the abort, exit or longjmp function. If func executes a return statement, and the value of i was INTFPE or any other implementation-defined value corresponding to a computational exception, the behavior is undefined. Otherwise, the program will resume execution at the point it was interrupted.
At program startup, the equivalent of handler(sig, INT_IGN); is executed for some interrupt selected in an implementation-defined manner, the equivalent of handler(i, INT_DFL); is executed for all other interrupts defined by the implementation.
If the request can be honored, the handler function returns the value of func for the most recent call to handler for the specified interrupt i. Otherwise a value of INT_ERR is returned and a positive value is stored in errno.
The abort function, Section 10.4.1
The exit function, Section 10.4.3