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Dear all,
I'm trying to check the register values in inline-assembly in c as the below code. In especially, R0 and R1 values what I want to know which value is loaded to register. But as you can see that code, that is a In-line assembly.
Is there any way to check the register which values are loaded?
main.c
... __asm void ST0(void) { MOVS R0,#0 LDR R1,[R0] ; Get initial MSP value MOV SP, R1 LDR R1,[R0, #4] ; Get initial PC value BX R1 } ... int main (void) { ST0(); return 0; }
Hello Carter,
You are using inline assembly here, so you are defining variables as R0, SP and so on. You are NOT using the actual registers on the device.
To modify the real registers, you would have to use embedded assembly.
See an example of embedded assembler:
#include <stdio.h> __asm void my_strcpy(const char *src, char *dst) { loop LDRB r2, [r0], #1 STRB r2, [r1], #1 CMP r2, #0 BNE loop BX lr } int main(void) { const char *a = "Hello world!"; char b[20]; my_strcpy (a, b); printf("Original string: '%s'\n", a); printf("Copied string: '%s'\n", b); return 0; }
(from infocenter.arm.com/.../index.jsp )
putting __asm in front of the function name lets you modify the registers directly.