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Add ATtiny2313. Implement printf

This commit is contained in:
jimmy 2024-04-20 09:37:55 +12:00
parent 05034f9256
commit a20e3d9836
2 changed files with 78 additions and 15 deletions
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86
src/usart.cpp
View File

@ -4,13 +4,7 @@
namespace usart
{
namespace {
static FILE mystdout;
}
void init( unsigned long baud) {
fdev_setup_stream(&mystdout, put_printf, NULL, _FDEV_SETUP_WRITE);
stdout = &mystdout;
const unsigned int ubrr = F_CPU/8/baud-1;
/*Set baud rate */
@ -34,6 +28,15 @@ namespace usart
//UCSRB |= (1<< RXCIE)|(1<<TXCIE);
/* Set frame format: 8data, 2stop bit */
UCSRC = (1 << URSEL)|(3<<UCSZ0);
#elif defined __AVR_ATtiny2313__
UBRRH = (unsigned char)(ubrr>>8);
UBRRL = (unsigned char)ubrr;
UCSRA |= (1<<U2X);
//Enable receiver and transmitter
UCSRB = (1<<RXEN)|(1<<TXEN);
//UCSRB |= (1<< RXCIE)|(1<<TXCIE);
/* Set frame format: 8data, 2stop bit */
UCSRC = (1<<USBS)|(3<<UCSZ0);
#endif
}
@ -43,23 +46,82 @@ namespace usart
while ( !( UCSR0A & (1<<UDRE0)) ); UDR0 = data;
#elif defined __AVR_ATmega32__ || defined __AVR_ATmega16__
while ( !( UCSRA & (1<<UDRE)) ); UDR = data;
#elif defined __AVR_ATtiny2313__
while ( !( UCSRA & (1<<UDRE)) ); UDR = data;
#endif
}
char get( void ) {
#if defined __AVR_ATmega328P__
while ( !(UCSR0A & (1<<RXC0)) ); return UDR0;
#elif defined __AVR_ATmega32__ || defined __AVR_ATmega16__
#elif defined __AVR_ATmega32__ || defined __AVR_ATmega16__ || defined __AVR_ATtiny2313__
while ( !(UCSRA & (1<<RXC)) ); return UDR;
#endif
}
int put_printf(char var, FILE *stream) {
put(var);
return 0;
void itoa(int n, char s[], int base) {
int i = 0;
int sign = n;
if (sign < 0) {
n = -n;
}
do {
s[i++] = n % base + '0';
} while ((n /= base) > 0);
if (sign < 0) {
s[i++] = '-';
}
s[i] = '\0';
// Reverse the string
for (int j = 0, k = i - 1; j < k; j++, k--) {
char temp = s[j];
s[j] = s[k];
s[k] = temp;
}
}
void printf(const char *fmt, ...) {
va_list args;
va_start(args, fmt);
for (const char *p = fmt; *p != '\0'; p++) {
if (*p == '%') {
switch (*(++p)) {
case 's': {
const char *s = va_arg(args, const char *);
for (; *s; s++) put(*s);
break;
}
case 'd':
case 'i': {
char buf[10];
itoa(va_arg(args, int), buf, 10);
for (char *s = buf; *s; s++) put(*s);
break;
}
case 'c':
put(va_arg(args, int));
break;
case 'x': {
char buf[10];
itoa(va_arg(args, int), buf, 16);
for (char *s = buf; *s; s++) put(*s);
break;
}
}
} else {
put(*p);
}
}
va_end(args);
}
} // namespace usart

1
src/usart.h
View File

@ -8,6 +8,7 @@ namespace usart
void put(char data );
char get();
int put_printf(char var, FILE *stream);
void printf(const char *var, ...);
} // namespace usart