这一版函数基于MSP430F169，%d %x %o %b的实现不再由自己编写函数，而是调用MSP430-GCC的标准库函数：

#include

char *itoa(int num, char *str, int radix);

send_fun函数指针，指向调用的UARTx的字节发送函数：

void uart_printf(send_fun fun, char *fmt, ...)

{

char *pnt = (char *)&fmt + sizeof(fmt);

char *str, buf[9];

int radix;

while (*fmt != '\0') {

if (*fmt != '%') {

fun(*fmt);

fmt += 1;

continue;

}

switch (*(fmt + 1)) {

case 'c':

fun(*((int *)pnt));

pnt += sizeof(int);

fmt += 2;

continue;

case 's':

str = (char *)*((int *)pnt);

while (*str != '\0')

fun(*str++);

pnt += sizeof(int);

fmt += 2;

continue;

case 'd':

radix = 10;

goto SEND_NUM;

case 'x':

radix = 16;

goto SEND_NUM;

case 'o':

radix = 8;

goto SEND_NUM;

case 'b':

radix = 2;

goto SEND_NUM;

SEND_NUM:

str = itoa(*(int *)pnt, buf, radix);

while (*str != '\0')

fun(*str++);

pnt += sizeof(int);

fmt += 2;

continue;

default:

break;

}

}

}

实际上，库stdio.h中也提供了printf的实现，直接调用它们就可以了：

int __attribute__((format (printf, 2, 3))) uprintf(int (*func)(int c), const char *fmt, ...);