PointerError - Example showing \"hang\" when reading from bad po…

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Example showing \"hang\" when reading from bad pointer, and catching this in the HardFault_Handler

main.cpp@0:333b2c3ec494, 2012-03-04 (annotated)

User	Revision	Line number	New contents of line
simon	0:333b2c3ec494	1	// Example of hanging when reading a bad pointer
simon	0:333b2c3ec494	2
simon	0:333b2c3ec494	3	#include "mbed.h"
simon	0:333b2c3ec494	4
simon	0:333b2c3ec494	5	DigitalOut myled(LED1);
simon	0:333b2c3ec494	6
simon	0:333b2c3ec494	7	int x[10] = {0};
simon	0:333b2c3ec494	8
simon	0:333b2c3ec494	9	extern "C" void HardFault_Handler() {
simon	0:333b2c3ec494	10	error("Hit HardFault handler!\n");
simon	0:333b2c3ec494	11	}
simon	0:333b2c3ec494	12
simon	0:333b2c3ec494	13	int main() {
simon	0:333b2c3ec494	14	int *ok_ptr = x;
simon	0:333b2c3ec494	15	int bad_ptr = (int)0xe600b0; // not in RAM!
simon	0:333b2c3ec494	16	printf("ok_ptr = 0x%08X, bad_ptr = 0x%08X\n", ok_ptr, bad_ptr);
simon	0:333b2c3ec494	17
simon	0:333b2c3ec494	18	int ok_read = ok_ptr[0];
simon	0:333b2c3ec494	19	printf("ok_read = %d\n", ok_read);
simon	0:333b2c3ec494	20
simon	0:333b2c3ec494	21	int bad_read = bad_ptr[0];
simon	0:333b2c3ec494	22	printf("bad_read = %d\n", bad_read);
simon	0:333b2c3ec494	23
simon	0:333b2c3ec494	24	while(1) {
simon	0:333b2c3ec494	25	myled = 1;
simon	0:333b2c3ec494	26	wait(0.2);
simon	0:333b2c3ec494	27	myled = 0;
simon	0:333b2c3ec494	28	wait(0.2);
simon	0:333b2c3ec494	29	}
simon	0:333b2c3ec494	30	}