Commander X16 hello world with CC65

demo.c

// save as demo.c and compile like this:
// cl65 -t c64 -O -o demo.prg demo.c

#include <stdint.h>
#include <cbm.h>

#define BSOUT(c) \
    __AX__ = c;  \
    asm("jsr BSOUT");
    
void print(const char* string)
{
    while (*string) {
        BSOUT(*string);
        string++;
    }
}

int main(void)
{
    // bad hack: redefine CC65 stack to $0xa800-0xafff, should be a proper x16 custom target
    *((uint16_t*) 0x02) = 0xb000;
    
    // switch back to uppercase character set
    BSOUT(0x8e);
    
    // print something
    print("hello world");
    
	return 0;
}