Subversion Repositories softavrcore

#define		F_CPU		12000000UL
 
#include <avr/cpufunc.h>
#include <avr/interrupt.h>
#include <inttypes.h>
#include <util/delay.h>
#include <stdio.h>
 
/*****************************************************************************/
 
#define		__IOR(x)	(*(volatile uint8_t *)(0x20+(x)))
#define		__IOW(x)	(*(volatile uint16_t *)(0x20+(x)))
 
/*****************************************************************************/
 
 
#define		IO_BASE_UART0		0x00
#define		IO_BASE_PORTOUT0	0x04
#define		IO_BASE_TIMER0		0x08
 
/* uart.h */
 
#define		UDR0		__IOR(IO_BASE_UART0+0x00)
#define		UCSRA0		__IOR(IO_BASE_UART0+0x01)
#define		UCSRB0		__IOR(IO_BASE_UART0+0x02)
#define		UBRR0		__IOR(IO_BASE_UART0+0x03)
 
/* UCSRA */
#define		RXB8		0
#define		PE		2
#define		DOR		3
#define		FE		4
#define		UDRE		5
#define		TXC		6
#define		RXC		7
 
/* UCSRB */
#define		TXB8		0
#define		UCSZ		1
#define		UPM0		2
#define		UPM1		3
#define		USBS		4
#define		UDRIE		5
#define		TXCIE		6
#define		RXCIE		7	
 
/* timer.h */
 
#define		TCNT0		__IOW(IO_BASE_TIMER0+0x00)
#define		TCR0		__IOR(IO_BASE_TIMER0+0x02)
#define		TSR0		__IOR(IO_BASE_TIMER0+0x03)
 
#define		TOF		7	/* timer overflow */
#define		TOFIE		7	/* timer overflow interrupt enable */
#define		TPRESC0		0	/* timer prescaler bit 0 */
#define		TPRESC1		1	/* timer prescaler bit 1 */
 
/* port.h */
 
#define		PORTOUT0	__IOR(IO_BASE_PORTOUT0+0x00)
 
/*****************************************************************************/
 
static int uart_putchar(char c, FILE *stream)
{
 loop_until_bit_is_set(UCSRA0, UDRE);
 UDR0 = c;
 return(0);
}
 
static FILE mystdout = FDEV_SETUP_STREAM(uart_putchar, NULL, _FDEV_SETUP_WRITE);
 
/*****************************************************************************/
 
/* RXC */
ISR(_VECTOR(3))
{
 uint8_t	c;
 c=UDR0;
 if ( 'a' <= c && c <= 'z' )     c-=('a'-'A');
 UDR0=c;
}
 
ISR(_VECTOR(1))
{
 TCR0=TCR0;
 PORTOUT0 ^= 0x02;
}
 
 
static inline void msleep(uint16_t msec)
{
 while ( msec )
  {	_delay_loop_2((uint32_t)F_CPU/4000UL);
	msec--;
  }
}
 
static void test_memory_buffer(void)
{
 static char *	string="0123456789";
 uint8_t	length=10,offset,cnt;
 
 msleep(10);
 
 offset=0;
 cnt=0;
 while ( 1 )
  {	uint8_t	c;
 
	while ( ! (UCSRA0&(1<<RXC)) );
	c=UDR0;
 
	if ( c != 10 )
	 {	c=string[offset];
		offset++;
		if ( length==offset )	offset=0;
	 }
 
	UDR0=c; 
	cnt++;
	PORTOUT0=cnt&3;
  };
 
 
}
 
static void test_uppercase(void)
{
 while ( 1 )
  {	uint8_t	c;
	while ( ! (UCSRA0&(1<<RXC)) );
	c=UDR0;
	if ( 'a' <= c && c <= 'z' )	c-=('a'-'A');
	while ( ! (UCSRA0&(1<<UDRE)) );
	UDR0=c; 
  };
 
}
 
static void test_printf(void)
{
 int	i;
 
 stdout=&mystdout;
 
 i=0;
 PORTOUT0 = 0x90;
 PORTOUT0 ^= 0x03;
 
 while ( 1 )
  {	PORTOUT0 ^= 0x03;
	printf("[x] %d => %d\n",i,i*i);
	msleep(1000);
	i++;
  }
}
 
void test_interrupt(void)
{
 UCSRB0 |= (1<<RXCIE);
 
 TCR0 = 0x02;
 TCR0 |= (1<<TOFIE);
 
 sei();
 while ( 1 )
  {	PORTOUT0 ^= 0x01;
	msleep(500);
  }
}
 
 
int main(void)
{
 uint8_t	c;
 
 UBRR0 = 13-1;
 
 test_printf();
 test_interrupt();
 test_uppercase();
 test_memory_buffer();
 
 c=0;
 while ( 1 )
  {	msleep(500);
	PORTOUT0=c;
	UDR0='a'+c;
	c=(c+1)%4;
  }
 test_uppercase();
 return(0);
}