如何将char转换成int然后以十六进制格式显示
How to convert char to int and then display it in hex format
我正在用 c 编写一个程序,其中我从串行设备获取数据并将其存储在缓冲区 char receivebuffer[100]
中。当我显示 receivebuffer 的内容时,输出显示 �
(Is this an ASCII format) 。但预期的输出是十六进制格式。如何将其转换为十六进制?
我也想知道,如果我把buffer转成int,输出结果会一样吗?请告诉我如何将 char 缓冲区也转换为 int?
#include <errno.h>
#include <termios.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
int set_interface_attribs (int fd, int speed, int parity)
{
struct termios tty;
memset (&tty, 0, sizeof tty);
if (tcgetattr (fd, &tty) != 0)
{
printf("error %d from tcgetattr\n\n", errno);
printf("Error Opening the device\n\n");
exit(0);
//error_message ("error %d from tcgetattr", errno);
return -1;
}
cfsetospeed (&tty, speed);
cfsetispeed (&tty, speed);
tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8; // 8-bit chars
// disable IGNBRK for mismatched speed tests; otherwise receive break
// as [=10=]0 chars
tty.c_iflag &= ~IGNBRK; // disable break processing
tty.c_lflag = 0; // no signaling chars, no echo,
// no canonical processing
tty.c_oflag = 0; // no remapping, no delays
tty.c_cc[VMIN] = 0; // read doesn't block
tty.c_cc[VTIME] = 5; // 0.5 seconds read timeout
tty.c_iflag &= ~(IXON | IXOFF | IXANY); // shut off xon/xoff ctrl
tty.c_cflag |= (CLOCAL | CREAD);// ignore modem controls,
// enable reading
tty.c_cflag &= ~(PARENB | PARODD); // shut off parity
tty.c_cflag |= parity;
tty.c_cflag &= ~CSTOPB;
tty.c_cflag &= ~CRTSCTS;
if (tcsetattr (fd, TCSANOW, &tty) != 0)
{
printf("error %d from tcsetattr\n\n", errno);
printf("Error Opening the device\n\n");
exit(0);
//error_message ("error %d from tcsetattr", errno);
return -1;
}
return 0;
}
void set_blocking (int fd, int should_block)
{
struct termios tty;
memset (&tty, 0, sizeof tty);
if (tcgetattr (fd, &tty) != 0)
{
printf("error\n\n");
printf("Error Opening the device\n\n");
exit(0);
//error_message ("error %d from tggetattr", errno);
return;
}
tty.c_cc[VMIN] = should_block ? 1 : 0;
tty.c_cc[VTIME] = 5; // 0.5 seconds read timeout
if (tcsetattr (fd, TCSANOW, &tty) != 0)
printf("Error Opening the device\n\n");
//error_message ("error %d setting term attributes", errno);
}
int main()
{
char *portname = "/dev/ttyUSB0";
int fd = open (portname, O_RDWR | O_NOCTTY | O_SYNC);
if (fd < 0)
{
//error_message ("error %d opening %s: %s", errno, portname, strerror (errno));
printf("error");
}
set_interface_attribs (fd, B9600, 0); // set speed to 115,200 bps, 8n1 (no parity)
set_blocking (fd, 0); // set no blocking
// send 7 character greeting
usleep ((7 + 25) * 100); // sleep enough to transmit the 7 plus
while(1)
{
char receivebuffer [100];
read (fd, receivebuffer, sizeof receivebuffer); // read up to 100 characters if ready to read
printf("value of buffer is %s\n\n", receivebuffer);
return 0;
}
}
您不需要转换它。要将 char
显示为十六进制数,请在 printf
函数组中使用 %hhx
格式。
你应该替换这个:
printf("value of buffer is %s\n\n", receivebuffer);
与:
for (int tmpfoo = 0; receivebuffer[tmpfoo] != '[=11=]'; tmpfoo++)
{
printf("value of buffer is %X\n\n", (int)receivebuffer[tmpfoo]);
}
如果您只想在 HEXvalue 后面跟着 HEXvalue。
您需要将接收到的字节数存储在某处并在 for 循环中使用它 像这样尝试
char receivebuffer[100];
int count;
int i;
count = read (fd, receivebuffer, sizeof receivebuffer); // read up to 100 characters if ready to read
for (i = 0 ; i < count ; ++i)
{
printf("0x%02X ", receivebuffer[i]);
if ((i + 1) % 8 == 0)
printf("\n");
}
这个if ((i + 1) % 8 == 0)
只是连续打印8
个字节,你可以更改或删除它,不过它有助于检查数据。
我正在用 c 编写一个程序,其中我从串行设备获取数据并将其存储在缓冲区 char receivebuffer[100]
中。当我显示 receivebuffer 的内容时,输出显示 �
(Is this an ASCII format) 。但预期的输出是十六进制格式。如何将其转换为十六进制?
我也想知道,如果我把buffer转成int,输出结果会一样吗?请告诉我如何将 char 缓冲区也转换为 int?
#include <errno.h>
#include <termios.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
int set_interface_attribs (int fd, int speed, int parity)
{
struct termios tty;
memset (&tty, 0, sizeof tty);
if (tcgetattr (fd, &tty) != 0)
{
printf("error %d from tcgetattr\n\n", errno);
printf("Error Opening the device\n\n");
exit(0);
//error_message ("error %d from tcgetattr", errno);
return -1;
}
cfsetospeed (&tty, speed);
cfsetispeed (&tty, speed);
tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8; // 8-bit chars
// disable IGNBRK for mismatched speed tests; otherwise receive break
// as [=10=]0 chars
tty.c_iflag &= ~IGNBRK; // disable break processing
tty.c_lflag = 0; // no signaling chars, no echo,
// no canonical processing
tty.c_oflag = 0; // no remapping, no delays
tty.c_cc[VMIN] = 0; // read doesn't block
tty.c_cc[VTIME] = 5; // 0.5 seconds read timeout
tty.c_iflag &= ~(IXON | IXOFF | IXANY); // shut off xon/xoff ctrl
tty.c_cflag |= (CLOCAL | CREAD);// ignore modem controls,
// enable reading
tty.c_cflag &= ~(PARENB | PARODD); // shut off parity
tty.c_cflag |= parity;
tty.c_cflag &= ~CSTOPB;
tty.c_cflag &= ~CRTSCTS;
if (tcsetattr (fd, TCSANOW, &tty) != 0)
{
printf("error %d from tcsetattr\n\n", errno);
printf("Error Opening the device\n\n");
exit(0);
//error_message ("error %d from tcsetattr", errno);
return -1;
}
return 0;
}
void set_blocking (int fd, int should_block)
{
struct termios tty;
memset (&tty, 0, sizeof tty);
if (tcgetattr (fd, &tty) != 0)
{
printf("error\n\n");
printf("Error Opening the device\n\n");
exit(0);
//error_message ("error %d from tggetattr", errno);
return;
}
tty.c_cc[VMIN] = should_block ? 1 : 0;
tty.c_cc[VTIME] = 5; // 0.5 seconds read timeout
if (tcsetattr (fd, TCSANOW, &tty) != 0)
printf("Error Opening the device\n\n");
//error_message ("error %d setting term attributes", errno);
}
int main()
{
char *portname = "/dev/ttyUSB0";
int fd = open (portname, O_RDWR | O_NOCTTY | O_SYNC);
if (fd < 0)
{
//error_message ("error %d opening %s: %s", errno, portname, strerror (errno));
printf("error");
}
set_interface_attribs (fd, B9600, 0); // set speed to 115,200 bps, 8n1 (no parity)
set_blocking (fd, 0); // set no blocking
// send 7 character greeting
usleep ((7 + 25) * 100); // sleep enough to transmit the 7 plus
while(1)
{
char receivebuffer [100];
read (fd, receivebuffer, sizeof receivebuffer); // read up to 100 characters if ready to read
printf("value of buffer is %s\n\n", receivebuffer);
return 0;
}
}
您不需要转换它。要将 char
显示为十六进制数,请在 printf
函数组中使用 %hhx
格式。
你应该替换这个:
printf("value of buffer is %s\n\n", receivebuffer);
与:
for (int tmpfoo = 0; receivebuffer[tmpfoo] != '[=11=]'; tmpfoo++)
{
printf("value of buffer is %X\n\n", (int)receivebuffer[tmpfoo]);
}
如果您只想在 HEXvalue 后面跟着 HEXvalue。
您需要将接收到的字节数存储在某处并在 for 循环中使用它 像这样尝试
char receivebuffer[100];
int count;
int i;
count = read (fd, receivebuffer, sizeof receivebuffer); // read up to 100 characters if ready to read
for (i = 0 ; i < count ; ++i)
{
printf("0x%02X ", receivebuffer[i]);
if ((i + 1) % 8 == 0)
printf("\n");
}
这个if ((i + 1) % 8 == 0)
只是连续打印8
个字节,你可以更改或删除它,不过它有助于检查数据。