Difference between revisions of "Matrix - Temperature Sensor"

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(使用方法)
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* Tiny, easy to be used in various situations
 
* Tiny, easy to be used in various situations
 
* 2.54mm spacing pin
 
* 2.54mm spacing pin
==使用方法==
+
==How To==
===连接===
+
===Connection===
*连接到Tiny4412 SDK (1506)
+
*Connect to Tiny4412 SDK (1506)
::GND针脚:   接地
+
::GND: Ground
::VCC:  接5V
+
::VCC:  5V
::S:接GPIO_PIN1
+
::S:  GPIO_PIN1
  
===Linux下的C示例===
+
===Code Sample in C Under Linux===
 
<syntaxhighlight lang="c">
 
<syntaxhighlight lang="c">
 
#include <stdio.h>
 
#include <stdio.h>
Line 95: Line 95:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
===编译并运行示例===
+
===Compile and Run===
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
git clone http://github.com/friendlyarm/fa-hardware.git
 
git clone http://github.com/friendlyarm/fa-hardware.git
Line 103: Line 103:
 
make
 
make
 
</syntaxhighlight>
 
</syntaxhighlight>
将编译生成的ds18b20通过ftp上传到开发板上运行即可测试。
+
Copy your compiled bin to your board and you are ready to go.
  
 
==相关资料==
 
==相关资料==

Revision as of 06:19, 7 August 2015

查看中文

1 Introduction

Temperature Sensor

非常流行的TO-92封装的DS18B20。DSl8B20的电源可以由数据线本身提供而不需要外部电源,因为每一个DSl8B20在出厂时已经给定了唯一的序列号。DS18B20的测量范围是-55摄氏度到+125摄氏度,可选9-bit或12-bit,在-10摄氏度到+85摄氏度时可以精确到0.5度,采用一线协议通讯。我们把DS18B20的3个针脚全部引出,V对应电源引脚,G对应地引脚,S对应数据引脚。

2 Features

  • -55 degree Celsius to +125 degree Celsius
  • 一线协议
  • Tiny, easy to be used in various situations
  • 2.54mm spacing pin

3 How To

3.1 Connection

  • Connect to Tiny4412 SDK (1506)
GND: Ground
VCC: 5V
S: GPIO_PIN1

3.2 Code Sample in C Under Linux

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "libfahw.h"
 
void parseCmd(int argc, char **argv, int *pin)
{
    int num = atoi(argv[1]);
    switch(num) {
    case 1:
        *pin = TINY4412_GPIO_PIN1;
        break;
    case 2:
        *pin = TINY4412_GPIO_PIN2;
        break;
    case 3:
        *pin = TINY4412_GPIO_PIN3;
        break;
    case 4:
        *pin = TINY4412_GPIO_PIN4;
        break;
    case 5:
        *pin = TINY4412_GPIO_PIN5;
        break;
    case 6:
        *pin = TINY4412_GPIO_PIN6;
        break;
    case 7:
        *pin = TINY4412_GPIO_PIN7;
        break;
    case 8:
        *pin = TINY4412_GPIO_PIN8;
        break;
    case 9:
        *pin = TINY4412_GPIO_PIN9;
        break;
    case 10:
        *pin = TINY4412_GPIO_PIN10;
        break;
    default:
        printf("Unsupported pin TINY4412_GPIO_PIN%d\n", num);
        num = 1;
        *pin = TINY4412_GPIO_PIN1;
        break;
    }
    printf("Using pin TINY4412_GPIO_PIN%d\n", num);
}
 
int main(int argc, char ** argv)
{
    int devFD = -1;
    int pin = TINY4412_GPIO_PIN1;
    char *temperature = (char *) malloc(32);
    memset(temperature, 0, 32);
 
    if (argc == 2) {
        parseCmd(argc, argv, &pin);
    } else {
        printf("Using default pin TINY4412_GPIO_PIN1\n");
    }
 
    if ((devFD = ds18b20Init(pin)) == -1) {
        printf("Fail to init ds18b20\n");
        return -1;
    }
    if (ds18b20Read(temperature) > 0) {
        printf("Temperature = %s\n", temperature);
    } else {
        printf("Fail to get temperature\n");
    }
    free(temperature);
    ds18b20DeInit(devFD);
    return 0;
}

3.3 Compile and Run

git clone http://github.com/friendlyarm/fa-hardware.git
cd fa-hardware
cd demo
cd matrix-temperature_sensor
make

Copy your compiled bin to your board and you are ready to go.

4 相关资料