Difference between revisions of "Matrix - Relay"

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[[Matrix - Relay/zh|查看中文]]
 
[[Matrix - Relay/zh|查看中文]]
  
−
==介绍==
+
==Introduction==
 
[[File:relay01.png|thumb|Relay]]
 
[[File:relay01.png|thumb|Relay]]
−
*模块Matrix-Relay这是一个单刀双掷继电器，通常应用于自动控制电路中，它实际上是用较小的电流去控制较大电流的一种“自动开关”。故在电路中起着自动调节、安全保护、转换电路等作用。
+
* The Matrix-Relay module is a SPDT relay which is an electrically operated switch. Relays are used where it is necessary to control a circuit by a low-power signal. In a electric system it is used to protect electrical circuits from overload or faults.
  
−
==特性==
+
==Features==
 
* 1 Form C
 
* 1 Form C
−
* 5V线圈电压，控制信号为3.3/5V
+
* 5V supply voltage, GPIO signal: 3.3/5V
−
* 触点电流可达10A
+
* Current on-contact up to 10A
−
* LED指示
+
* LED indicator
−
* 2.54mm排针接口，接线方便，通用性强
+
* 2.54 mm spacing pin
−
* PCB尺寸（mm）：24x48
+
* PCB dimension (mm): 24 x 48
 
[[File:relaypcb.png|frameless|400px|继电器PCB]]
 
[[File:relaypcb.png|frameless|400px|继电器PCB]]
  
−
* 引脚说明:
+
* Pin Description:
 
{| class="wikitable"
 
{| class="wikitable"
 
|-
 
|-
−
|名称 || 描述
+
|Pin || Description
 
|-
 
|-
 
|S    || GPIO
 
|S    || GPIO
 
|-
 
|-
−
|V    || 电源5V
+
|V    || Supply Voltage 5V
 
|-
 
|-
−
|G    || 地
+
|G    || Ground
 
|}
 
|}
  
−
==工作原理==
+
==Basic Device Operation==
−
这是一个单刀双掷继电器，线圈电压为直流5V，触点电流可达10A，适合驱动直流或交流大功率负载。NO为常开触点，NC为常闭触点，COM为公共触点。当向S引脚施加高电平，继电器线圈导通，此时NO触点断开，NC触点闭合。
+
This is an SPDT relay. Its supply voltage is 5V and current on-contact is up to 10A. It can drive AC or DC high power loads. NO is Normally Open. NC is Normally Closed. COM is Common. When writing high to pin S NO will be open and NC will be closed.
  
−
==下载Matrix源码==
 
−
Matrix配件相关的代码是完全开源的，统一由一个仓库进行管理：git://github.com/friendlyarm/matrix.git <br>
 
−
该仓库里不同的分支代表着Matrix配件所支持的不同开发板。<br>
 
−
* nanopi分支包含了Matrix对NanoPi的支持；
 
−
* tiny4412分支包含了Matrix对Tiny4412的支持；
 
−
* raspberrypi分支包含了Matrix对RaspberryPi的支持；
 
  
−
在主机PC上安装git，以Ubuntu14.04为例
+
==Applications==
 +
===Connect to NanoPi M1===
 +
Refer to the following connection diagram to connect the module to the NanoPi M1:<br>
 +
[[File:Matrix-Relay_nanopi_m1.jpg|frameless|600px|Matrix-Relay_nanopi_m1]]
 +
 
 +
Connection Details:
 +
{| class="wikitable"
 +
|-
 +
|Matrix-Relay || NanoPi M1
 +
|-
 +
|S    || Pin7
 +
|-
 +
|V    || Pin4
 +
|-
 +
|G    || Pin6
 +
|}
 +
 
 +
===Connect to NanoPi 2===
 +
Refer to the following connection diagram to connect the module to the NanoPi 2:<br>
 +
[[File:Matrix-Relay_nanopi_2.jpg|frameless|600px|Matrix-Relay_nanopi_2]]
 +
 
 +
Connection Details:
 +
{| class="wikitable"
 +
|-
 +
|Matrix-Relay || NanoPi 2
 +
|-
 +
|S    || Pin7
 +
|-
 +
|V    || Pin4
 +
|-
 +
|G    || Pin6
 +
|}
 +
 
 +
===Connect to NanoPi M2 / NanoPi 2 Fire===
 +
Refer to the following connection diagram to connect the module to the NanoPi M2/ NanoPi 2 Fire:<br>
 +
[[File:Matrix-Relay_nanopi_m2.jpg|frameless|600px|Matrix-Relay_nanopi_m2]]
 +
 
 +
Connection Details:
 +
{| class="wikitable"
 +
|-
 +
|Matrix-Relay || NanoPi M2
 +
|-
 +
|S    || Pin7
 +
|-
 +
|V    || Pin4
 +
|-
 +
|G    || Pin6
 +
|}
 +
 
 +
===Connect to NanoPC-T2===
 +
Refer to the following connection diagram to connect the module to the NanoPC-T2:<br>
 +
[[File:Matrix-Relay_NanoPC-T2.jpg|frameless|600px|Matrix-Relay_NanoPC-T2]]
 +
 
 +
Connection Details:
 +
{| class="wikitable"
 +
|-
 +
|Matrix-Relay || NanoPC-T2
 +
|-
 +
|S    || Pin15
 +
|-
 +
|V    || Pin29
 +
|-
 +
|G    || Pin30
 +
|}
 +
 
 +
==Compile & Run Test Program==
 +
Boot your ARM board with Debian and copy the matrix code:
 +
<syntaxhighlight lang="bash">
 +
$ apt-get update && apt-get install git
 +
$ git clone https://github.com/friendlyarm/matrix.git
 +
</syntaxhighlight>
 +
If your cloning is done successfully a "matrix" directory will be generated.
 +
 
 +
Compile and install Matrix:
 +
<syntaxhighlight lang="bash">
 +
$ cd matrix
 +
$ make && make install
 +
</syntaxhighlight>
 +
 
 +
Run test program:
 +
<syntaxhighlight lang="bash">
 +
$ matrix-gpio_out
 +
</syntaxhighlight>
 +
Note: this module is not plug and play therefore before running the module please make sure it is connected to an ARM board.<br>
 +
Here is what you should observe:<br>
 +
<syntaxhighlight lang="bash">
 +
1: gpio status change
 +
2: gpio status change
 +
3: gpio status change
 +
4: gpio status change
 +
5: gpio status change
 +
</syntaxhighlight>
 +
 
 +
==Code Sample==
 +
This Matrix code sample can work with all the ARM boards mentioned in this module's wiki. The name of this code sample is "matrix-gpio_out". Here is its source code:
 +
<syntaxhighlight lang="c">
 +
int main(int argc, char ** argv)
 +
{
 +
    int pin = GPIO_PIN(7);
 +
    int i, value, board;
 +
    int ret = -1;
 +
   
 +
    if ((board = boardInit()) < 0) {
 +
        printf("Fail to init board\n");
 +
        return -1;
 +
    }
 +
    if (board == BOARD_NANOPI_T2)
 +
        pin = GPIO_PIN(15);
 +
   
 +
    if (argc == 2)
 +
        pin = GPIO_PIN(atoi(argv[1]));
 +
    if ((ret = exportGPIOPin(pin)) == -1) { 
 +
        printf("exportGPIOPin(%d) failed\n", pin);
 +
    }
 +
    if ((ret = setGPIODirection(pin, GPIO_OUT)) == -1) {
 +
        printf("setGPIODirection(%d) failed\n", pin);
 +
    }
 +
    for (i = 0; i < STATUS_CHANGE_TIMES; i++) {
 +
        if (i % 2) {
 +
            value = GPIO_HIGH;
 +
        } else {
 +
            value = GPIO_LOW;
 +
        }
 +
        if ((ret = setGPIOValue(pin, value)) > 0) {
 +
            printf("%d: GPIO_PIN(%d) value is %d\n", i+1, pin, value);
 +
        } else {
 +
            printf("setGPIOValue(%d) failed\n", pin);
 +
        }
 +
        sleep(1);
 +
    }
 +
    unexportGPIOPin(pin);
 +
    return 0;
 +
}
 +
</syntaxhighlight>
 +
For more details about this APIs called in this code sample refer to [[Matrix API reference manual]] <br>
 +
<!---
 +
==Download Matrix Source Code==
 +
All the matrix modules' code samples are open source. They are maintained on GitHub - https://github.com/friendlyarm/matrix.git <br>
 +
Each branch in this hub contains the matrix modules' code samples for a board that the matrix modules can work with.<br>
 +
* The nanopi branch contains the matrix modules' code samples for the NanoPi
 +
* The nanopi 2 branch contains the matrix modules' code samples for the NanoPi 2
 +
* The tiny4412 branch contains the matrix modules' code samples for the Tiny4412
 +
* The raspberrypi branch contains the matrix modules' code samples for the RaspberryPi
 +
 
 +
Please follow the steps below to get the source code:<br>
 +
Install the git utility on a PC running Ubuntu14.04
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ sudo apt-get install git
 
$ sudo apt-get install git
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
克隆Matrix配件代码仓库
+
Clone the matrix code from GitHub
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
−
$ git clone git://github.com/friendlyarm/matrix.git
+
$ git clone https://github.com/friendlyarm/matrix.git
 +
</syntaxhighlight>
 +
If this is successful a "matrix" directory will be generated, which will contain all the matrix modules' code samples.
 +
 
 +
==Connect to NanoPi 2==
 +
===Hardware Connection===
 +
Please refer to the following connection diagram to connect the Matrix-Relay to the NanoPi 2:<br>
 +
[[File:Matrix-Relay_nanopi_2.jpg|frameless|600px|Matrix-Relay_nanopi_2]]
 +
 
 +
Connection Details:
 +
{| class="wikitable"
 +
|-
 +
|Matrix-Relay || NanoPi 2
 +
|-
 +
|S  || Pin7
 +
|-
 +
|V  || Pin4
 +
|-
 +
|G  || Pin6
 +
|}
 +
 
 +
===Compile Test Program===
 +
Please login the matrix hub and enter the nanopi2 branch
 +
<syntaxhighlight lang="bash">
 +
$ cd matrix
 +
$ git checkout nanopi2
 +
</syntaxhighlight>
 +
 
 +
Compile the matrix code
 +
<syntaxhighlight lang="bash">
 +
$ make CROSS_COMPILE=arm-linux- clean
 +
$ make CROSS_COMPILE=arm-linux-
 +
$ make CROSS_COMPILE=arm-linux- install
 +
</syntaxhighlight>
 +
Note: please make sure to install the cross compiler "arm-linux-gcc-4.9.3" on your PC, which is used to compile files for the NanoPi2.<br>
 +
Generated library files are under the "install/lib" directory. Applications are under the "install/usr/bin" directory. The test program for the "Matrix-Relay" module is "matrix-relay".<br>
 +
The driver is under the modules directory and its source code is in github: https://github.com/friendlyarm/linux-3.4.y.git <br>
 +
 
 +
===Run Test Program===
 +
Please insert a TF card which is flashed with Debian to a Linux host and mount its boot and rootfs sections.<br>
 +
We assume the rootfs is mounted to /media/rootfs then please run the following commands to copy the driver, library and test program to the card.<br>
 +
<syntaxhighlight lang="bash">
 +
$ cp modules /media/rootfs/ -r
 +
$ cp install/lib/* /media/rootfs/lib/ -d
 +
$ cp install/usr/bin/* /media/rootfs/usr/bin/
 +
</syntaxhighlight>
 +
 
 +
Insert this TF card to your NanoPi 2, power on and run the following command to start matrix-relay.<br>
 +
<syntaxhighlight lang="bash">
 +
$ matrix-relay
 +
</syntaxhighlight>
 +
Note: this module is not plug and play therefore before running the module please make sure it is connected to a NanoPi 2.
 +
 
 +
===Code Sample===
 +
<syntaxhighlight lang="c">
 +
int main(int argc, char ** argv)
 +
{
 +
    char *status = "off";
 +
    if (argc != 2) {
 +
        printf("Set relay on\n");
 +
    } else {
 +
        status = argv[1];
 +
        printf("Set relay %s\n", argv[1]);
 +
    }
 +
 
 +
    int pin = GPIO_PIN(7);
 +
    int ret = -1;
 +
    if ((ret = exportGPIOPin(pin)) != 0) { 
 +
        printf("exportGPIOPin(%d) failed!", pin);
 +
    }
 +
    if ((ret = setGPIODirection(pin, GPIO_OUT)) != 0) {
 +
        printf("setGPIODirection(%d) failed", pin);
 +
    }
 +
 
 +
    if (strcmp(status, "on") == 0) {
 +
        ret = setGPIOValue(pin, GPIO_HIGH);
 +
    } else if (strcmp(status, "off") == 0) {
 +
        ret = setGPIOValue(pin, GPIO_LOW);
 +
    }
 +
    return ret;
 +
}
 
</syntaxhighlight>
 
</syntaxhighlight>
−
克隆完成后会得到一个matrix目录，里面存放着所有Matrix配件的代码。
 
  
−
==与NanoPi连接使用==
+
==Connect to NanoPi==
−
===准备工作===
+
===Preparations===
−
在NanoPi上运行Debian系统，然后在主机PC上安装并使用相应的编译器。参考wiki：[[NanoPi/zh|NanoPi]] <br>
+
Please install a Debian on a NanoPi and an appropriate cross compiler on a PC. Please refer to wiki:[[NanoPi/zh|NanoPi]] <br>
−
注意：必须使用nanopi-v4.1.y-matrix分支编译出来的内核。<br>
+
Compile a NanoPi kernel. Note: please use the kernel's source code from the nanopi-v4.1.y-matrix branch.<br>
−
下载NanoPi内核源代码并编译
+
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ git clone https://github.com/friendlyarm/linux-4.x.y.git
 
$ git clone https://github.com/friendlyarm/linux-4.x.y.git
Line 61: Line 278:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
===硬件连接===
+
===Hardware Connection===
−
参考下图连接模块Matrix-Relay和NanoPi <br>
+
Please refer to the following connection diagram to connect the Matrix-Relay to the NanoPi <br>
 
[[File:matrix-relay_nanopi.jpg|frameless|600px|matrix-relay_nanopi]]
 
[[File:matrix-relay_nanopi.jpg|frameless|600px|matrix-relay_nanopi]]
  
−
连接说明：
+
Connection Details:
 
{| class="wikitable"
 
{| class="wikitable"
 
|-
 
|-
Line 77: Line 294:
 
|}
 
|}
  
−
===编译测试程序===
+
===Compile Test Program===
−
进入Matrix代码仓库，切换到nanopi分支
+
Please login the matrix hub and enter the nanopi branch
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ cd matrix
 
$ cd matrix
Line 84: Line 301:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
编译Matrix配件代码
+
Compile the matrix code
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ make CROSS_COMPILE=arm-linux- clean
 
$ make CROSS_COMPILE=arm-linux- clean
Line 90: Line 307:
 
$ make CROSS_COMPILE=arm-linux- install
 
$ make CROSS_COMPILE=arm-linux- install
 
</syntaxhighlight>
 
</syntaxhighlight>
−
注意：请确保你的主机PC当前使用的交叉编译器为NanoPi-Debian配套的arm-linux-gcc-4.4.3。<br>
+
Note: please make sure to install the cross compiler "arm-linux-gcc-4.4.3" on your PC, which is used to compile files for the NanoPi-Debian.<br>
−
编译出来的库文件位于install/lib目录下，而测试程序则位于install/usr/bin目录下，模块Matrix-Relay对应的测试程序为matrix-relay。<br>
+
Generated library files are under the "install/lib" directory. Applications are under the "install/usr/bin" directory. The test program for the "Matrix-Relay" module is "matrix-relay".<br>
  
−
===运行测试程序===
+
===Run Test Program===
−
拷贝库文件和测试程序到NanoPi的文件系统上
+
Please copy the library files and test program to the NanoPi
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ cp install/usr/bin/* nanopi_rootfs/usr/bin/
 
$ cp install/usr/bin/* nanopi_rootfs/usr/bin/
Line 100: Line 317:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
然后启动NanoPi，在Debian的shell终端中执行如下命令运行模块Matrix-Relay的测试程序 <br>
+
Power on the NanoPi and run the following command in Debian's terminal <br>
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ matrix-relay
 
$ matrix-relay
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
===代码展示===
+
===Code Sample===
 
<syntaxhighlight lang="c">
 
<syntaxhighlight lang="c">
 
#include <stdio.h>
 
#include <stdio.h>
Line 139: Line 356:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
==与Tiny4412连接使用==
+
==Connect to Tiny4412==
−
===准备工作===
+
===Preparations===
−
参考Tiny4412光盘里的《友善之臂Ubuntu使用手册》，在Tiny4412上运行UbuntuCore系统，然后在主机PC上安装并使用相应的编译器。<br>
+
Please refer to the Tiny4412's user's manual to install a UbuntuCore on the Tiny4412 and install an appropriate cross compiler on a PC.<br>
−
注意：只能使用Tiny4412SDK-1506的底板。
+
Note: only the Tiny4412SDK-1506 carrier board can work with this module.
  
−
===硬件连接===
+
===Hardware Connection===
−
参考下图连接模块Matrix-Relay和Tiny4412 <br>
+
Please refer to the following diagram to connect the Matrix-Relay to the Tiny4412 <br>
 
[[File:matrix-relay_tiny4412.jpg|frameless|600px|matrix-relay_tiny4412]]
 
[[File:matrix-relay_tiny4412.jpg|frameless|600px|matrix-relay_tiny4412]]
  
−
连接说明：
+
Connection Details:
 
{| class="wikitable"
 
{| class="wikitable"
 
|-
 
|-
Line 161: Line 378:
  
  
−
===编译测试程序===
+
===Compile Test Program===
−
进入Matrix代码仓库，切换到tiny4412分支
+
Please login the Matrix hub and enter the matrix-tiny4412 branch
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ cd matrix
 
$ cd matrix
Line 168: Line 385:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
编译Matrix配件代码
+
Compile the matrix code
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ make CROSS_COMPILE=arm-linux-gnueabihf- clean
 
$ make CROSS_COMPILE=arm-linux-gnueabihf- clean
Line 174: Line 391:
 
$ make CROSS_COMPILE=arm-linux-gnueabihf- install
 
$ make CROSS_COMPILE=arm-linux-gnueabihf- install
 
</syntaxhighlight>
 
</syntaxhighlight>
−
注意：请确保你的主机PC当前使用的交叉编译器为Tiny4412-UbuntuCore配套的arm-linux-gnueabihf-gcc-4.7.3。<br>
+
Note: please make sure to install the cross compiler "arm-linux-gnueabihf-gcc-4.7.3" on your PC, which is used to compile files for the Tiny4412-UbuntuCore.<br>
−
编译出来的库文件位于install/lib目录下，而测试程序则位于install/usr/bin目录下，模块Matrix-Relay对应的测试程序为matrix-relay。
+
Generated library files are under the "install/lib" directory. Applications are under the "install/usr/bin" directory. The test program for the "Matrix-Relay" module is "matrix-relay".
  
−
===运行测试程序===
+
===Run Test Program===
−
拷贝库文件和测试程序到Tiny4412的UbuntuCore的文件系统上
+
Please copy the library files and test program to the Tiny4412
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ cp install/usr/bin/* tiny4412_rootfs/usr/bin/
 
$ cp install/usr/bin/* tiny4412_rootfs/usr/bin/
Line 184: Line 401:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
然后启动Tiny4412，在UbuntuCore的shell终端中执行如下命令运行模块Matrix-Relay的测试程序 <br>
+
Power on the Tiny4412 and run the following command in UbuntuCore's terminal <br>
 
<syntaxhighlight lang="bash">
 
<syntaxhighlight lang="bash">
 
$ matrix-relay
 
$ matrix-relay
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
===代码展示===
+
===Code Sample===
 
<syntaxhighlight lang="c">
 
<syntaxhighlight lang="c">
 
#include <stdio.h>
 
#include <stdio.h>
Line 223: Line 440:
 
</syntaxhighlight>
 
</syntaxhighlight>
  
−
==与RaspberryPi连接使用==
+
==Connect to RaspberryPi==
  
−
==与Arduino连接使用==
+
==Connect to Arduino==
 +
--->
  
−
==相关资料==
+
==Resources==
 
[http://www.micro4you.com/files/sensor/DHT11.pdf DHT11.pdf]
 
[http://www.micro4you.com/files/sensor/DHT11.pdf DHT11.pdf]
 +
 +
==Update Log==
 +
===Feb-19-2016===
 +
* Added Section 5
 +
===June-23-2016===
 +
* Re-organized and simplified wiki

Latest revision as of 15:04, 23 June 2016

查看中文

1 Introduction

Relay
  • The Matrix-Relay module is a SPDT relay which is an electrically operated switch. Relays are used where it is necessary to control a circuit by a low-power signal. In a electric system it is used to protect electrical circuits from overload or faults.

2 Features

  • 1 Form C
  • 5V supply voltage, GPIO signal: 3.3/5V
  • Current on-contact up to 10A
  • LED indicator
  • 2.54 mm spacing pin
  • PCB dimension (mm): 24 x 48

继电器PCB

  • Pin Description:
Pin Description
S GPIO
V Supply Voltage 5V
G Ground

3 Basic Device Operation

This is an SPDT relay. Its supply voltage is 5V and current on-contact is up to 10A. It can drive AC or DC high power loads. NO is Normally Open. NC is Normally Closed. COM is Common. When writing high to pin S NO will be open and NC will be closed.


4 Applications

4.1 Connect to NanoPi M1

Refer to the following connection diagram to connect the module to the NanoPi M1:
Matrix-Relay_nanopi_m1

Connection Details:

Matrix-Relay NanoPi M1
S Pin7
V Pin4
G Pin6

4.2 Connect to NanoPi 2

Refer to the following connection diagram to connect the module to the NanoPi 2:
Matrix-Relay_nanopi_2

Connection Details:

Matrix-Relay NanoPi 2
S Pin7
V Pin4
G Pin6

4.3 Connect to NanoPi M2 / NanoPi 2 Fire

Refer to the following connection diagram to connect the module to the NanoPi M2/ NanoPi 2 Fire:
Matrix-Relay_nanopi_m2

Connection Details:

Matrix-Relay NanoPi M2
S Pin7
V Pin4
G Pin6

4.4 Connect to NanoPC-T2

Refer to the following connection diagram to connect the module to the NanoPC-T2:
Matrix-Relay_NanoPC-T2

Connection Details:

Matrix-Relay NanoPC-T2
S Pin15
V Pin29
G Pin30

5 Compile & Run Test Program

Boot your ARM board with Debian and copy the matrix code: 

$ apt-get update && apt-get install git
$ git clone https://github.com/friendlyarm/matrix.git

If your cloning is done successfully a "matrix" directory will be generated.

Compile and install Matrix: 

$ cd matrix
$ make && make install

Run test program: 

$ matrix-gpio_out

Note: this module is not plug and play therefore before running the module please make sure it is connected to an ARM board.
Here is what you should observe:

1: gpio status change
2: gpio status change
3: gpio status change
4: gpio status change
5: gpio status change

6 Code Sample

This Matrix code sample can work with all the ARM boards mentioned in this module's wiki. The name of this code sample is "matrix-gpio_out". Here is its source code: 

int main(int argc, char ** argv) 
{
    int pin = GPIO_PIN(7); 
    int i, value, board;
    int ret = -1;
 
    if ((board = boardInit()) < 0) {
        printf("Fail to init board\n");
        return -1;
    }
    if (board == BOARD_NANOPI_T2)
        pin = GPIO_PIN(15);
 
    if (argc == 2)
        pin = GPIO_PIN(atoi(argv[1]));
    if ((ret = exportGPIOPin(pin)) == -1) {   
        printf("exportGPIOPin(%d) failed\n", pin);
    }
    if ((ret = setGPIODirection(pin, GPIO_OUT)) == -1) {
        printf("setGPIODirection(%d) failed\n", pin);
    }
    for (i = 0; i < STATUS_CHANGE_TIMES; i++) {
        if (i % 2) {
            value = GPIO_HIGH;
        } else {
            value = GPIO_LOW;
        }
        if ((ret = setGPIOValue(pin, value)) > 0) {
            printf("%d: GPIO_PIN(%d) value is %d\n", i+1, pin, value);
        } else {
            printf("setGPIOValue(%d) failed\n", pin);
        }
        sleep(1);
    }
    unexportGPIOPin(pin);
    return 0;
}

For more details about this APIs called in this code sample refer to Matrix API reference manual

7 Resources

DHT11.pdf

8 Update Log

8.1 Feb-19-2016

  • Added Section 5

8.2 June-23-2016

  • Re-organized and simplified wiki
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