Stc8a8k64d4 (51 Series MCU) printf printing data abnormal problem

Problem phenomenon

I am using STC8A8K64D4 MCU to do a project , Use printf An exception occurred while the function was printing debugging information with parameters （ Redirected correctly printf function ）, The specific performance defines 8 Bit variables use %X The value printed out in the format becomes 16 position , And the assignment is 0 Then print out 16 Random value of bit ; And then define a 16 Bit variables , Use %d Format printing , Nor can the value of the variable be printed correctly , And print the values of other exceptions , Use the serial port to send a single byte function , Send the upper eight bits and the lower eight bits respectively , And print out the value of the variable correctly ; And format the data into a string Use %s You can print data normally

Problem solving

Access to information ,51 Single chip microcomputer adopt printf When printing formatted data , Out of commission %d Placeholders like that , Instead, use the following placeholders ：

1. The first thing to do is to determine printf Has been correctly redirected to the specified serial port

/********************* Printf  Redirection function  ************************/
#if(PRINTF_SEL == 1)

char putchar(char c)
{
    
	TX1_write2buff(c);
	return c;
}

#elif(PRINTF_SEL == 2)

char putchar(char c)
{
    
	TX2_write2buff(c);
	return c;
}

#elif(PRINTF_SEL == 3)

char putchar(char c)
{
    
	TX3_write2buff(c);
	return c;
}

#elif(PRINTF_SEL == 4)

char putchar(char c)
{
    
	TX4_write2buff(c);
	return c;
}

#endif

2. 51 Use of single chip microcomputer printf when , Formatted data is , Use the formatting symbols in the above table , The specific tests are as follows ：

/*  Put the function in  mian  Function   Check the printed value  */
void test51printf(void)
{
    
	 unsigned char a = 128;
	 char 	b = -15 ;
	 unsigned short c = 256;
	 short d = -25;
	 unsigned int 	e = 65535;
	 int f = -32765;

	printf("a=%bu b=%bd c=%hu d=%hd e=%hu f=%hd \r\n",a,b,c,d,e,f);
	printf("\r\n size(a)=%bu,size(c)=%bu,size(e)=%bu \r\n"  ,sizeof(a),sizeof(c),sizeof(e));
}

The results are as follows ：

a=128 b=-15 c=256 d=-25 e=65535 f=-32765 

size(a)=1,size(c)=2,size(e)=2

Data can be printed normally , Problem solving ！

PS：51 In the single chip microcomputer int = short int = 2 Bytes