前面我们实现了好用的串口收发接口，进一步我们来实现基于串口的输入输出，方便后面交互打印信息等。
参考微信公众号”嵌入式Lee”的文章
https://mp.weixin.qq.com/s/y4MHV3cd4T0b51L5M4J5Xg 极海半导体APM32F107VC开发板-移植超轻量级标准输入输出函数库xprintf
Xprintf.c如下
/*------------------------------------------------------------------------/
/ Universal String Handler for Console Input and Output
/-------------------------------------------------------------------------/
/
/ Copyright (C) 2021, ChaN, all right reserved.
/
/ xprintf module is an open source software. Redistribution and use of
/ xprintf module in source and binary forms, with or without modification,
/ are permitted provided that the following condition is met:
/
/ 1. Redistributions of source code must retain the above copyright notice,
/ this condition and the following disclaimer.
/
/ This software is provided by the copyright holder and contributors "AS IS"
/ and any warranties related to this software are DISCLAIMED.
/ The copyright owner or contributors be NOT LIABLE for any damages caused
/ by use of this software.
/
/-------------------------------------------------------------------------*/
#include "xprintf.h"
#define SZB_OUTPUT 32
#if XF_USE_OUTPUT
#include <stdarg.h>
void (*xfunc_output)(int); /* Pointer to the default output device */
static char *strptr; /* Pointer to the output memory (used by xsprintf) */
#if XF_USE_FP
/*----------------------------------------------*/
/* Floating point output */
/*----------------------------------------------*/
#include <math.h>
static int ilog10 (double n) /* Calculate log10(n) in integer output */
{
int rv = 0;
while (n >= 10) { /* Decimate digit in right shift */
if (n >= 100000) {
n /= 100000; rv += 5;
} else {
n /= 10; rv++;
}
}
while (n < 1) { /* Decimate digit in left shift */
if (n < 0.00001) {
n *= 100000; rv -= 5;
} else {
n *= 10; rv--;
}
}
return rv;
}
static double i10x (int n) /* Calculate 10^n */
{
double rv = 1;
while (n > 0) { /* Left shift */
if (n >= 5) {
rv *= 100000; n -= 5;
} else {
rv *= 10; n--;
}
}
while (n < 0) { /* Right shift */
if (n <= -5) {
rv /= 100000; n += 5;
} else {
rv /= 10; n++;
}
}
return rv;
}
static void ftoa (
char* buf, /* Buffer to output the generated string */
double val, /* Real number to output */
int prec, /* Number of fractinal digits */
char fmt /* Notation */
)
{
int d;
int e = 0, m = 0;
char sign = 0;
double w;
const char *er = 0;
if (isnan(val)) { /* Not a number? */
er = "NaN";
} else {
if (prec < 0) prec = 6; /* Default precision (6 fractional digits) */
if (val < 0) { /* Nagative value? */
val = -val; sign = '-';
} else {
sign = '+';
}
if (isinf(val)) { /* Infinite? */
er = "INF";
} else {
if (fmt == 'f') { /* Decimal notation? */
val += i10x(-prec) / 2; /* Round (nearest) */
m = ilog10(val);
if (m < 0) m = 0;
if (m + prec + 3 >= SZB_OUTPUT) er = "OV"; /* Buffer overflow? */
} else { /* E notation */
if (val != 0) { /* Not a true zero? */
val += i10x(ilog10(val) - prec) / 2; /* Round (nearest) */
e = ilog10(val);
if (e > 99 || prec + 6 >= SZB_OUTPUT) { /* Buffer overflow or E > +99? */
er = "OV";
} else {
if (e < -99) e = -99;
val /= i10x(e); /* Normalize */
}
}
}
}
if (!er) { /* Not error condition */
if (sign == '-') *buf++ = sign; /* Add a - if negative value */
do { /* Put decimal number */
w = i10x(m); /* Snip the highest digit d */
d = val / w; val -= d * w;
if (m == -1) *buf++ = XF_DPC; /* Insert a decimal separarot if get into fractional part */
*buf++ = '0' + d; /* Put the digit */
} while (--m >= -prec); /* Output all digits specified by prec */
if (fmt != 'f') { /* Put exponent if needed */
*buf++ = fmt;
if (e < 0) {
e = -e; *buf++ = '-';
} else {
*buf++ = '+';
}
*buf++ = '0' + e / 10;
*buf++ = '0' + e % 10;
}
}
}
if (er) { /* Error condition? */
if (sign) *buf++ = sign; /* Add sign if needed */
do *buf++ = *er++; while (*er); /* Put error symbol */
}
*buf = 0; /* Term */
}
#endif /* XF_USE_FLOAT */
/*----------------------------------------------*/
/* Put a character */
/*----------------------------------------------*/
void xputc (
int chr /* Character to be output */
)
{
xfputc(xfunc_output, chr); /* Output it to the default output device */
}
void xfputc ( /* Put a character to the specified device */
void(*func)(int), /* Pointer to the output function (null:strptr) */
int chr /* Character to be output */
)
{
if (XF_CRLF && chr == '\n') xfputc(func, '\r'); /* CR -> CRLF */
if (func) {
func(chr); /* Write a character to the output device */
} else if (strptr) {
*strptr++ = chr; /* Write a character to the memory */
}
}
/*----------------------------------------------*/
/* Put a null-terminated string */
/*----------------------------------------------*/
void xputs ( /* Put a string to the default device */
const char* str /* Pointer to the string */
)
{
xfputs(xfunc_output, str);
}
void xfputs ( /* Put a string to the specified device */
void(*func)(int), /* Pointer to the output function */
const char* str /* Pointer to the string */
)
{
while (*str) { /* Put the string */
xfputc(func, *str++);
}
}
/*----------------------------------------------*/
/* Formatted string output */
/*----------------------------------------------*/
/* xprintf("%d", 1234); "1234"
xprintf("%6d,%3d%%", -200, 5); " -200, 5%"
xprintf("%-6u", 100); "100 "
xprintf("%ld", 12345678); "12345678"
xprintf("%llu", 0x100000000); "4294967296" <XF_USE_LLI>
xprintf("%lld", -1LL); "-1" <XF_USE_LLI>
xprintf("%04x", 0xA3); "00a3"
xprintf("%08lX", 0x123ABC); "00123ABC"
xprintf("%016b", 0x550F); "0101010100001111"
xprintf("%*d", 6, 100); " 100"
xprintf("%s", "String"); "String"
xprintf("%5s", "abc"); " abc"
xprintf("%-5s", "abc"); "abc "
xprintf("%-5s", "abcdefg"); "abcdefg"
xprintf("%-5.5s", "abcdefg"); "abcde"
xprintf("%-.5s", "abcdefg"); "abcde"
xprintf("%-5.5s", "abc"); "abc "
xprintf("%c", 'a'); "a"
xprintf("%12f", 10.0); " 10.000000" <XF_USE_FP>
xprintf("%.4E", 123.45678); "1.2346E+02" <XF_USE_FP>
*/
static void xvfprintf (
void(*func)(int), /* Pointer to the output function */
const char* fmt, /* Pointer to the format string */
va_list arp /* Pointer to arguments */
)
{
unsigned int r, i, j, w, f;
int n, prec;
char str[SZB_OUTPUT], c, d, *p, pad;
#if XF_USE_LLI
long long v;
unsigned long long uv;
#else
long v;
unsigned long uv;
#endif
for (;;) {
c = *fmt++; /* Get a format character */
if (!c) break; /* End of format? */
if (c != '%') { /* Pass it through if not a % sequense */
xfputc(func, c); continue;
}
f = w = 0; /* Clear parms */
pad = ' '; prec = -1;
c = *fmt++; /* Get first char of the sequense */
if (c == '0') { /* Flag: left '0' padded */
pad = '0'; c = *fmt++;
} else {
if (c == '-') { /* Flag: left justified */
f = 2; c = *fmt++;
}
}
if (c == '*') { /* Minimum width from an argument */
n = va_arg(arp, int);
if (n < 0) { /* Flag: left justified */
n = 0 - n; f = 2;
}
w = n; c = *fmt++;
} else {
while (c >= '0' && c <= '9') { /* Minimum width */
w = w * 10 + c - '0';
c = *fmt++;
}
}
if (c == '.') { /* Precision */
c = *fmt++;
if (c == '*') { /* Precision from an argument */
prec = va_arg(arp, int);
c = *fmt++;
} else {
prec = 0;
while (c >= '0' && c <= '9') {
prec = prec * 10 + c - '0';
c = *fmt++;
}
}
}
if (c == 'l') { /* Prefix: Size is long */
f |= 4; c = *fmt++;
#if XF_USE_LLI
if (c == 'l') { /* Prefix: Size is long long */
f |= 8; c = *fmt++;
}
#endif
}
if (!c) break; /* End of format? */
switch (c) { /* Type is... */
case 'b': /* Unsigned binary */
r = 2; break;
case 'o': /* Unsigned octal */
r = 8; break;
case 'd': /* Signed decimal */
case 'u': /* Unsigned decimal */
r = 10; break;
case 'x': /* Hexdecimal (lower case) */
case 'X': /* Hexdecimal (upper case) */
r = 16; break;
case 'c': /* A character */
xfputc(func, (char)va_arg(arp, int)); continue;
case 's': /* String */
p = va_arg(arp, char*); /* Get a pointer argument */
if (!p) p = ""; /* Null ptr generates a null string */
j = strlen(p);
if (prec >= 0 && j > (unsigned int)prec) j = prec; /* Limited length of string body */
for ( ; !(f & 2) && j < w; j++) xfputc(func, pad); /* Left pads */
while (*p && prec--) xfputc(func, *p++);/* String body */
while (j++ < w) xfputc(func, ' '); /* Right pads */
continue;
#if XF_USE_FP
case 'f': /* Float (decimal) */
case 'e': /* Float (e) */
case 'E': /* Float (E) */
ftoa(p = str, va_arg(arp, double), prec, c); /* Make fp string */
for (j = strlen(p); !(f & 2) && j < w; j++) xfputc(func, pad); /* Left pads */
while (*p) xfputc(func, *p++); /* Value */
while (j++ < w) xfputc(func, ' '); /* Right pads */
continue;
#endif
default: /* Unknown type (passthrough) */
xfputc(func, c); continue;
}
/* Get an integer argument and put it in numeral */
#if XF_USE_LLI
if (f & 8) { /* long long argument? */
v = (long long)va_arg(arp, long long);
} else {
if (f & 4) { /* long argument? */
v = (c == 'd') ? (long long)va_arg(arp, long) : (long long)va_arg(arp, unsigned long);
} else { /* int/short/char argument */
v = (c == 'd') ? (long long)va_arg(arp, int) : (long long)va_arg(arp, unsigned int);
}
}
#else
if (f & 4) { /* long argument? */
v = (long)va_arg(arp, long);
} else { /* int/short/char argument */
v = (c == 'd') ? (long)va_arg(arp, int) : (long)va_arg(arp, unsigned int);
}
#endif
if (c == 'd' && v < 0) { /* Negative value? */
v = 0 - v; f |= 1;
}
i = 0; uv = v;
do { /* Make an integer number string */
d = (char)(uv % r); uv /= r;
if (d > 9) d += (c == 'x') ? 0x27 : 0x07;
str[i++] = d + '0';
} while (uv != 0 && i < sizeof str);
if (f & 1) str[i++] = '-'; /* Sign */
for (j = i; !(f & 2) && j < w; j++) xfputc(func, pad); /* Left pads */
do xfputc(func, str[--i]); while (i != 0); /* Value */
while (j++ < w) xfputc(func, ' '); /* Right pads */
}
}
void xprintf ( /* Put a formatted string to the default device */
const char* fmt, /* Pointer to the format string */
... /* Optional arguments */
)
{
va_list arp;
va_start(arp, fmt);
xvfprintf(xfunc_output, fmt, arp);
va_end(arp);
}
void xfprintf ( /* Put a formatted string to the specified device */
void(*func)(int), /* Pointer to the output function */
const char* fmt, /* Pointer to the format string */
... /* Optional arguments */
)
{
va_list arp;
va_start(arp, fmt);
xvfprintf(func, fmt, arp);
va_end(arp);
}
void xsprintf ( /* Put a formatted string to the memory */
char* buff, /* Pointer to the output buffer */
const char* fmt, /* Pointer to the format string */
... /* Optional arguments */
)
{
va_list arp;
strptr = buff; /* Enable destination for memory */
va_start(arp, fmt);
xvfprintf(0, fmt, arp);
va_end(arp);
*strptr = 0; /* Terminate output string */
strptr = 0; /* Disable destination for memory */
}
#if XF_USE_DUMP
/*----------------------------------------------*/
/* Dump a line of binary dump */
/*----------------------------------------------*/
void put_dump (
const void* buff, /* Pointer to the array to be dumped */
unsigned long addr, /* Heading address value */
int len, /* Number of items to be dumped */
size_t width /* Size of buff[0] (1, 2 or 4) */
)
{
int i;
const unsigned char *bp;
const unsigned short *sp;
const unsigned long *lp;
xprintf("%08lX ", addr); /* address */
switch (width) {
case sizeof (char):
bp = buff;
for (i = 0; i < len; i++) { /* Hexdecimal dump in (char) */
xprintf(" %02X", bp[i]);
}
xputs(" ");
for (i = 0; i < len; i++) { /* ASCII dump */
xputc((unsigned char)((bp[i] >= ' ' && bp[i] <= '~') ? bp[i] : '.'));
}
break;
case sizeof (short):
sp = buff;
do { /* Hexdecimal dump in (short) */
xprintf(" %04X", *sp++);
} while (--len);
break;
case sizeof (long):
lp = buff;
do { /* Hexdecimal dump in (short) */
xprintf(" %08lX", *lp++);
} while (--len);
break;
}
xputc('\n');
}
#endif /* XF_USE_DUMP */
#endif /* XF_USE_OUTPUT */
#if XF_USE_INPUT
int (*xfunc_input)(void); /* Pointer to the default input stream */
/*----------------------------------------------*/
/* Get a line from the input */
/*----------------------------------------------*/
int xgets ( /* 0:End of stream, 1:A line arrived */
char* buff, /* Pointer to the buffer */
int len /* Buffer length */
)
{
int c, i;
if (!xfunc_input) return 0; /* No input function is specified */
i = 0;
for (;;) {
c = xfunc_input(); /* Get a char from the incoming stream */
if (c < 0 || c == '\r') break; /* End of stream or CR? */
if (c == '\b' && i) { /* BS? */
i--;
if (XF_INPUT_ECHO) xputc(c);
continue;
}
if (c >= ' ' && i < len - 1) { /* Visible chars? */
buff[i++] = c;
if (XF_INPUT_ECHO) xputc(c);
}
}
if (XF_INPUT_ECHO) {
xputc('\r');
xputc('\n');
}
buff[i] = 0; /* Terminate with a \0 */
return (int)(c == '\r');
}
/*----------------------------------------------*/
/* Get a value of integer string */
/*----------------------------------------------*/
/* "123 -5 0x3ff 0b1111 0377 w "
^ 1st call returns 123 and next ptr
^ 2nd call returns -5 and next ptr
^ 3rd call returns 1023 and next ptr
^ 4th call returns 15 and next ptr
^ 5th call returns 255 and next ptr
^ 6th call fails and returns 0
*/
int xatoi ( /* 0:Failed, 1:Successful */
char **str, /* Pointer to pointer to the string */
long *res /* Pointer to the valiable to store the value */
)
{
unsigned long val;
unsigned char c, r, s = 0;
*res = 0;
while ((c = **str) == ' ') (*str)++; /* Skip leading spaces */
if (c == '-') { /* negative? */
s = 1;
c = *(++(*str));
}
if (c == '0') {
c = *(++(*str));
switch (c) {
case 'x': /* hexdecimal */
r = 16; c = *(++(*str));
break;
case 'b': /* binary */
r = 2; c = *(++(*str));
break;
default:
if (c <= ' ') return 1; /* single zero */
if (c < '0' || c > '9') return 0; /* invalid char */
r = 8; /* octal */
}
} else {
if (c < '0' || c > '9') return 0; /* EOL or invalid char */
r = 10; /* decimal */
}
val = 0;
while (c > ' ') {
if (c >= 'a') c -= 0x20;
c -= '0';
if (c >= 17) {
c -= 7;
if (c <= 9) return 0; /* invalid char */
}
if (c >= r) return 0; /* invalid char for current radix */
val = val * r + c;
c = *(++(*str));
}
if (s) val = 0 - val; /* apply sign if needed */
*res = val;
return 1;
}
#if XF_USE_FP
/*----------------------------------------------*/
/* Get a value of the real number string */
/*----------------------------------------------*/
/* Float version of xatoi
*/
int xatof ( /* 0:Failed, 1:Successful */
char **str, /* Pointer to pointer to the string */
double *res /* Pointer to the valiable to store the value */
)
{
double val;
int s, f, e;
unsigned char c;
*res = 0;
s = f = 0;
while ((c = **str) == ' ') (*str)++; /* Skip leading spaces */
if (c == '-') { /* Negative? */
c = *(++(*str)); s = 1;
} else if (c == '+') { /* Positive? */
c = *(++(*str));
}
if (c == XF_DPC) { /* Leading dp? */
f = -1; /* Start at fractional part */
c = *(++(*str));
}
if (c <= ' ') return 0; /* Wrong termination? */
val = 0;
while (c > ' ') { /* Get a value of decimal */
if (c == XF_DPC) { /* Embedded dp? */
if (f < 0) return 0; /* Wrong dp? */
f = -1; /* Enter fractional part */
} else {
if (c < '0' || c > '9') break; /* End of decimal? */
c -= '0';
if (f == 0) { /* In integer part */
val = val * 10 + c;
} else { /* In fractional part */
val += i10x(f--) * c;
}
}
c = *(++(*str));
}
if (c > ' ') { /* It may be an exponent */
if (c != 'e' && c != 'E') return 0; /* Wrong character? */
c = *(++(*str));
if (c == '-') {
c = *(++(*str)); s |= 2; /* Negative exponent */
} else if (c == '+') {
c = *(++(*str)); /* Positive exponent */
}
if (c <= ' ') return 0; /* Wrong termination? */
e = 0;
while (c > ' ') { /* Get value of exponent */
c -= '0';
if (c > 9) return 0; /* Not a numeral? */
e = e * 10 + c;
c = *(++(*str));
}
val *= i10x((s & 2) ? -e : e); /* Apply exponent */
}
if (s & 1) val = -val; /* Negate sign if needed */
*res = val;
return 1;
}
#endif /* XF_USE_FP */
#endif /* XF_USE_INPUT */
Xprintf.h如下
/*------------------------------------------------------------------------*/
/* Universal string handler for user console interface (C)ChaN, 2021 */
/*------------------------------------------------------------------------*/
#ifndef XPRINTF_DEF
#define XPRINTF_DEF
#include <string.h>
#ifdef __cplusplus
extern "C" {
#endif
#define XF_USE_OUTPUT 1 /* 1: Enable output functions */
#define XF_CRLF 1 /* 1: Convert \n ==> \r\n in the output char */
#define XF_USE_DUMP 1 /* 1: Enable put_dump function */
#define XF_USE_LLI 1 /* 1: Enable long long integer in size prefix ll */
#define XF_USE_FP 1 /* 1: Enable support for floating point in type e and f */
#define XF_DPC '.' /* Decimal separator for floating point */
#define XF_USE_INPUT 1 /* 1: Enable input functions */
#define XF_INPUT_ECHO 0 /* 1: Echo back input chars in xgets function */
#if defined(__GNUC__) && __GNUC__ >= 10
#pragma GCC diagnostic ignored "-Wcast-function-type"
#endif
#if XF_USE_OUTPUT
#define xdev_out(func) xfunc_output = (void(*)(int))(func)
extern void (*xfunc_output)(int);
void xputc (int chr);
void xfputc (void (*func)(int), int chr);
void xputs (const char* str);
void xfputs (void (*func)(int), const char* str);
void xprintf (const char* fmt, ...);
void xsprintf (char* buff, const char* fmt, ...);
void xfprintf (void (*func)(int), const char* fmt, ...);
void put_dump (const void* buff, unsigned long addr, int len, size_t width);
#endif
#if XF_USE_INPUT
#define xdev_in(func) xfunc_input = (int(*)(void))(func)
extern int (*xfunc_input)(void);
int xgets (char* buff, int len);
int xatoi (char** str, long* res);
int xatof (char** str, double* res);
#endif
#ifdef __cplusplus
}
#endif
#endif
blinky_thread_entry.c中实现接口
static void xprintf_out_port(int ch)
{
uint8_t val = ch;
uart_send(&val,1);
}
static int xprintf_in_port(void)
{
uint32_t len;
uint8_t val;
do
{
len = uart_read(&val,1);
}while(len == 0);
return val;
}
设置接口，blinky_thread_entry中初始化
xdev_out(xprintf_out_port);
xdev_in(xprintf_in_port);
测试代码如下
#include "xprintf.h"
/* Blinky Thread entry function */
void blinky_thread_entry (void * pvParameters)
{
uart_init();
xdev_out(xprintf_out_port);
xdev_in(xprintf_in_port);
while(1)
{
//static uint8_t rx_buffer[64];
//uint32_t rlen = uart_read(rx_buffer,sizeof(rx_buffer));
//if(rlen > 0)
//{
// uart_send(rx_buffer,rlen);
//}
xprintf("%d\n", 1234); /* "1234" */
xprintf("%6d,%3d%%\n", -200, 5); /* " -200, 5%" */
xprintf("%-6u\n", 100); /* "100 " */
xprintf("%ld\n", 12345678); /* "12345678" */
xprintf("%llu\n", 0x100000000); /* "4294967296" <XF_USE_LLI> */
xprintf("%lld\n", -1LL); /* "-1" <XF_USE_LLI> */
xprintf("%04x\n", 0xA3); /* "00a3" */
xprintf("%08lX\n", 0x123ABC); /* "00123ABC" */
xprintf("%016b\n", 0x550F); /* "0101010100001111" */
xprintf("%*d\n", 6, 100); /* " 100" */
xprintf("%s\n", "abcdefg"); /* "abcdefg" */
xprintf("%5s\n", "abc"); /* " abc" */
xprintf("%-5s\n", "abc"); /* "abc " */
xprintf("%.5s\n", "abcdefg"); /* "abcde" */
xprintf("%-5.2s\n", "abcdefg"); /* "ab " */
xprintf("%c\n", 'a'); /* "a" */
xprintf("%12f\n", 10.0); /* " 10.000000" <XF_USE_FP> */
xprintf("%.4E\n", 123.45678); /* "1.2346E+02" <XF_USE_FP> */
while(1)
{
char input_buffer[32];
char* str = input_buffer;
xprintf("please input two int\r\n");
xgets(input_buffer, sizeof(input_buffer));
long a;
xatoi(&str,&a);
long b;
xatoi(&str,&b);
xprintf("%d+%d=%d\r\n",a,b,a+b);
}
}
测试效果如下
打印正常，输入正常
提升卡
变色卡
千斤顶
1/6 
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