PL0_test.c


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#include "uart.h"
#include "psr.h"

void PL0_main(void)
{
  uart_puts("hello PL0! Switching to user mode!\n\r");

  // if all went correct, Success! gets printed
  uart_puts("Success!\n\r");

  // if we're indeed i PL0, we should crash now, when trying to access
  // memory we're not allowed to
  char first_kernel_byte[2];

  first_kernel_byte[0] = *(char*) ((uint32_t) 0x8000);
  first_kernel_byte[1] = '\0';
  
  uart_puts(first_kernel_byte);
    
  while (1)
    {
      char c = uart_getc();

      uart_putc(c);
      
      if (c == '\r')
	uart_putc('\n');
    }
}