Difference between revisions of "Matrix - Temperature and Humidity Sensor"
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[[Matrix - Temperature and Humidity Sensor/zh|查看中文]] | [[Matrix - Temperature and Humidity Sensor/zh|查看中文]] | ||
+ | ==Introduction== | ||
+ | [[File:TemperatureAndHumiditySensor01.png|thumb|Temperature and Humidity Sensor]] | ||
+ | * The Matrix-Temperature_and_Humidity_Sensor module is used to detect temperature and humidity. | ||
+ | * It utilizes the DHT11 temperature and humidity sensor. Its humidity range is 20% - 80% and the accuracy is 5%. Its temperature range is 0℃ - 50℃ and the accuracy is ±2℃. | ||
+ | |||
+ | ==Features== | ||
+ | * Humidity range: 20 - 80%RH, Temperature range 0 ~ 50℃ | ||
+ | * Accuracy of humidity: +-5%RH, accuracy of temperature: +-2℃ | ||
+ | * One wire communication | ||
+ | * 2.54 mm spacing pin | ||
+ | * PCB dimension (mm): 16 x 32 | ||
+ | [[File:dht11pcb.png|frameless|400px|温湿度传感器PCB]] | ||
+ | |||
+ | Pin Description: <br> | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Pin || Description | ||
+ | |- | ||
+ | |S || GPIO | ||
+ | |- | ||
+ | |V || Supply Voltage 5V | ||
+ | |- | ||
+ | |G || Ground | ||
+ | |} | ||
+ | |||
+ | ==Basic Device Operation== | ||
+ | The DHT11 module uses a simplified single-bus serial communication. DATA controls communication and synchronization between the microprocessor and DHT11. A data transfer takes 4ms. The data format contains an integer part and a decimal part. The basic operation is as follows: | ||
+ | * a transmission of 40 data, the high first-out | ||
+ | * data format: 8bit humidity integer data + 8bit the Humidity decimal data <br> | ||
+ | * 8bit temperature integer data + 8bit fractional temperature data <br> | ||
+ | * 8 bit parity bit <br> | ||
+ | * If a transmission is successful the “8bit humidity integer data + 8bit humidity decimal data +8 bit temperature integer data + 8bit temperature fractional data” 8bit checksum is equal to the results of the last eight. <br> | ||
+ | * After the user host (MCU) sends a signal DHT11 is converted from low-power mode to high-speed mode, until the host begins to signal the end. Then DHT11 sends a response signal to send 40bit data, and trigger a letter collection. If DHT11 doesn't receive a signal from the host it will not begin a letter collection. After the letter collection is done DHT11 will turn to low power mode. | ||
+ | |||
+ | |||
+ | ==Applications== | ||
+ | ===Connect to NanoPi M1=== | ||
+ | Refer to the following connection diagram to connect the module to the NanoPi M1:<br> | ||
+ | [[File:Matrix-Temperature_and_Humidity_Sensor_nanopi_m1.jpg|frameless|600px|Matrix-Temperature_and_Humidity_Sensor_nanopi_m1]] | ||
+ | |||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || 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-Temperature_and_Humidity_Sensor_nanopi_2.jpg|frameless|600px|Matrix-Temperature_and_Humidity_Sensor_nanopi_2]] | ||
+ | |||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || 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-Temperature_and_Humidity_Sensor_nanopi_m2.jpg|frameless|600px|Matrix-Temperature_and_Humidity_Sensor_nanopi_m2]] | ||
+ | |||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || 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-Temperature_and_Humidity_Sensor_NanoPC-T2.jpg|frameless|600px|Matrix-Temperature_and_Humidity_Sensor_NanoPC-T2]] | ||
+ | |||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || 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-temp_humidity | ||
+ | </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"> | ||
+ | The humidity is 35000 | ||
+ | The temperature is 26000 | ||
+ | </syntaxhighlight> | ||
+ | The module successfully read the environment's humidity and temperature values. | ||
+ | |||
+ | ==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-temperature_and_humidity_sensor". Here is its source code: | ||
+ | <syntaxhighlight lang="c"> | ||
+ | int main(int argc, char ** argv) | ||
+ | { | ||
+ | int ret = -1; | ||
+ | int dhtTemp=0, dhtHdty=0, board; | ||
+ | char modStr[BUF_SIZE]; | ||
+ | int pin = GPIO_PIN(7); | ||
+ | |||
+ | if ((board = boardInit()) < 0) { | ||
+ | printf("Fail to init board\n"); | ||
+ | return -1; | ||
+ | } | ||
+ | if (board == BOARD_NANOPI_T2) | ||
+ | pin = GPIO_PIN(15); | ||
+ | |||
+ | sprintf(modStr, "modprobe %s gpio=%d", DRIVER_MODULE, pintoGPIO(pin)); | ||
+ | system(modStr); | ||
+ | if ((ret = dht11Read(DHT_HUMIDITY, &dhtHdty)) != -1) { | ||
+ | printf("The humidity is %d\n", dhtHdty); | ||
+ | } else { | ||
+ | printf("Faided to get humidity\n"); | ||
+ | } | ||
+ | if ((ret = dht11Read(DHT_TEMP, &dhtTemp)) != -1) { | ||
+ | printf("The temperature is %d\n", dhtTemp); | ||
+ | } else { | ||
+ | printf("Faided to get temperature\n"); | ||
+ | } | ||
+ | system("rmmod "DRIVER_MODULE); | ||
+ | return ret; | ||
+ | } | ||
+ | </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"> | ||
+ | $ sudo apt-get install git | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | Clone the matrix code from GitHub | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ 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-Temperature_and_Humidity_Sensor to the NanoPi 2:<br> | ||
+ | [[File:Matrix-Temperature_and_Humidity_Sensor_nanopi_2.jpg|frameless|600px|Matrix-Temperature_and_Humidity_Sensor_nanopi_2]] | ||
+ | |||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || 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 NanoPi 2.<br> | ||
+ | Generated library files are under the "install/lib" directory. The test program is under the "install/usr/bin" directory.<br> | ||
+ | The modules are under the "modules" directory. The driver's 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 module, 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 commands to load the driver.<br> | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ cd /modules | ||
+ | $ insmod dht11.ko | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | Start the matrix-temp_humidity program.<br> | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ matrix-temp_humidity | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | Here is what you expect to observe:<br> | ||
+ | [[File:matrix-temp_humidity_result.png|frameless|600px|matrix-temp_humidity_result]] <br> | ||
+ | |||
+ | ===Code Sample=== | ||
+ | <syntaxhighlight lang="c"> | ||
+ | int main(int argc, char ** argv) | ||
+ | { | ||
+ | int ret = -1; | ||
+ | int dhtTemp = 0; | ||
+ | int dhtHdty = 0; | ||
+ | |||
+ | if ((ret = dht11Read(DHT_HUMIDITY, &dhtHdty)) != -1) { | ||
+ | printf("Get humidity : %d\n", dhtHdty); | ||
+ | } else { | ||
+ | printf("Faided to get humidity\n"); | ||
+ | } | ||
+ | |||
+ | if ((ret = dht11Read(DHT_TEMP, &dhtTemp)) != -1) { | ||
+ | printf("Get temperature : %d\n", dhtTemp); | ||
+ | } else { | ||
+ | printf("Faided to get temperature\n"); | ||
+ | } | ||
+ | |||
+ | return ret; | ||
+ | } | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | ==Connect to NanoPi== | ||
+ | ===Preparations=== | ||
+ | Please install a Debian on a NanoPi and an appropriate cross compiler on a PC. Please refer to wiki:[[NanoPi/zh|NanoPi]] <br> | ||
+ | Compile a NanoPi kernel. Note: please use the kernel's source code from the nanopi-v4.1.y-matrix branch.<br> | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ git clone https://github.com/friendlyarm/linux-4.x.y.git | ||
+ | $ cd linux-4.x.y | ||
+ | $ git checkout nanopi-v4.1.y-matrix | ||
+ | $ make nanopi_defconfig | ||
+ | $ touch .scmversion | ||
+ | $ make | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | ===Hardware Connection=== | ||
+ | Please refer to the following connection diagram to connect the Matrix-Temperature_and_Humidity_Sensor to the NanoPi <br> | ||
+ | [[File:matrix-temperature_and_humidity_sensor_nanopi.jpg|frameless|600px|matrix-temperature_and_humidity_sensor_nanopi]] | ||
+ | <br> | ||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || NanoPi | ||
+ | |- | ||
+ | |S || Pin7 | ||
+ | |- | ||
+ | |V || Pin4 | ||
+ | |- | ||
+ | |G || Pin6 | ||
+ | |} | ||
+ | |||
+ | ===Compile Test Program=== | ||
+ | Please login the matrix hub and enter the nanopi branch | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ cd matrix | ||
+ | $ git checkout nanopi | ||
+ | </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-4.4.3" on your PC, which is used to compile files for the NanoPi-Debian.<br> | ||
+ | Generated library files are under the "install/lib" directory. Applications are under the "install/usr/bin" directory. The test program for the "Matrix-Temperature_and_Humidity_Sensor" module is "matrix-temp_humidity".<br> | ||
+ | |||
+ | ===Run Test Program=== | ||
+ | Please copy the library files and test program to the NanoPi | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ cp install/usr/usr/bin/* nanopi_rootfs/usr/usr/bin/ | ||
+ | $ cp install/lib/* nanopi_rootfs/lib/ -d | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | Power on the NanoPi and run the following command in Debian's terminal <br> | ||
+ | Note: this module is not plug and play therefore before running the module please make sure it is connected to a NanoPi. | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ matrix-temp_humidity | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | ===Code Sample=== | ||
+ | <syntaxhighlight lang="c"> | ||
+ | int main(int argc, char ** argv) | ||
+ | { | ||
+ | int ret = -1; | ||
+ | int dhtTemp = 0; | ||
+ | int dhtHdty = 0; | ||
+ | int devFD = -1; | ||
+ | int pin = GPIO_PIN1; | ||
+ | |||
+ | if (argc == 2) { | ||
+ | parseCmd(argc, argv, &pin); | ||
+ | } else { | ||
+ | printf("Using default pin GPIO_PIN1\n"); | ||
+ | } | ||
+ | if ((devFD = dht11Init(pin)) == -1) { | ||
+ | printf("Fail to init dht11\n"); | ||
+ | return -1; | ||
+ | } | ||
+ | |||
+ | if ((ret = dht11Read(DHT_HUMIDITY, &dhtHdty)) != -1) { | ||
+ | printf("Get humidity : %d\n", dhtHdty); | ||
+ | } else { | ||
+ | printf("Faided to get humidity\n"); | ||
+ | } | ||
+ | |||
+ | if ((ret = dht11Read(DHT_TEMP, &dhtTemp)) != -1) { | ||
+ | printf("Get temperature : %d\n", dhtTemp); | ||
+ | } else { | ||
+ | printf("Faided to get temperature\n"); | ||
+ | } | ||
+ | |||
+ | dht11DeInit(devFD); | ||
+ | return ret; | ||
+ | } | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | ==Connect to Tiny4412== | ||
+ | ===Preparations=== | ||
+ | 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> | ||
+ | Note: only the Tiny4412SDK-1506 carrier board can work with this module. | ||
+ | |||
+ | ===Hardware Connection=== | ||
+ | Please refer to the following diagram to connect the Matrix-Temperature_and_Humidity_Sensor to the Tiny4412 <br> | ||
+ | [[File:matrix-temperature_and_humidity_sensor_tiny4412.jpg|frameless|600px|matrix-temperature_and_humidity_sensor_tiny4412]] | ||
+ | |||
+ | Connection Details: | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | |Matrix-Temperature_and_Humidity_Sensor || Tiny4412 | ||
+ | |- | ||
+ | |S || GPIO1 S | ||
+ | |- | ||
+ | |V || GPIO1 5V | ||
+ | |- | ||
+ | |G || GPIO1 GND | ||
+ | |} | ||
+ | |||
+ | ===Compile Test Program=== | ||
+ | Please login the Matrix hub and enter the matrix-tiny4412 branch | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ cd matrix | ||
+ | $ git checkout tiny4412 | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | Compile the matrix code | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ make CROSS_COMPILE=arm-linux-gnueabihf- clean | ||
+ | $ make CROSS_COMPILE=arm-linux-gnueabihf- | ||
+ | $ make CROSS_COMPILE=arm-linux-gnueabihf- install | ||
+ | </syntaxhighlight> | ||
+ | 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> | ||
+ | Generated library files are under the "install/lib" directory. Applications are under the "install/usr/bin" directory. The test program for the "Matrix-Temperature_and_Humidity_Sensor" module is "matrix-temp_humidity". | ||
+ | |||
+ | ===Run Test Program=== | ||
+ | Please copy the library files and test program to the Tiny4412 | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ cp install/usr/usr/bin/* tiny4412_rootfs/usr/usr/bin/ | ||
+ | $ cp install/lib/* tiny4412_rootfs/lib/ -d | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | Power on the Tiny4412 and run the following command in UbuntuCore's terminal <br> | ||
+ | Note: this module is not plug and play therefore before running the module please make sure it is connected to a Tiny4412. | ||
+ | <syntaxhighlight lang="bash"> | ||
+ | $ matrix-temp_humidity | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | ===Code Sample=== | ||
+ | <syntaxhighlight lang="c"> | ||
+ | int main(int argc, char ** argv) | ||
+ | { | ||
+ | int ret = -1; | ||
+ | int dhtTemp = 0; | ||
+ | int dhtHdty = 0; | ||
+ | int devFD = -1; | ||
+ | int pin = GPIO_PIN1; | ||
+ | |||
+ | if (argc == 2) { | ||
+ | parseCmd(argc, argv, &pin); | ||
+ | } else { | ||
+ | printf("Using default pin GPIO_PIN1\n"); | ||
+ | } | ||
+ | if ((devFD = dht11Init(pin)) == -1) { | ||
+ | printf("Fail to init dht11\n"); | ||
+ | return -1; | ||
+ | } | ||
+ | |||
+ | if ((ret = dht11Read(DHT_HUMIDITY, &dhtHdty)) != -1) { | ||
+ | printf("Get humidity : %d\n", dhtHdty); | ||
+ | } else { | ||
+ | printf("Faided to get humidity\n"); | ||
+ | } | ||
+ | |||
+ | if ((ret = dht11Read(DHT_TEMP, &dhtTemp)) != -1) { | ||
+ | printf("Get temperature : %d\n", dhtTemp); | ||
+ | } else { | ||
+ | printf("Faided to get temperature\n"); | ||
+ | } | ||
+ | |||
+ | dht11DeInit(devFD); | ||
+ | return ret; | ||
+ | } | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | ==Connect to RaspberryPi== | ||
+ | |||
+ | ==Connect to Arduino== | ||
+ | ---> | ||
+ | |||
+ | ==Resources== | ||
+ | [http://akizukidenshi.com/download/ds/aosong/DHT11.pdf DHT11.pdf] | ||
+ | |||
+ | ==Update Log== | ||
+ | ===Feb-23-2016=== | ||
+ | * Added the description for "NanoPi 2 branch" in Section 4 | ||
+ | * Added Section 5: Connect to NanoPi 2 | ||
+ | ===June-24-2016=== | ||
+ | * Re-organized and simplified wiki | ||
+ | |||
+ | |||
+ | <!-- | ||
==Introduction== | ==Introduction== | ||
[[File:TemperatureAndHumiditySensor01.png|thumb|Temperature and Humidity Sensor]] | [[File:TemperatureAndHumiditySensor01.png|thumb|Temperature and Humidity Sensor]] | ||
Line 8: | Line 470: | ||
* Humidity range: 20-80%RH, temperature range: 0~50℃ | * Humidity range: 20-80%RH, temperature range: 0~50℃ | ||
* Humidity accuracy:±5%RH, temperature accuracy: ±2℃ | * Humidity accuracy:±5%RH, temperature accuracy: ±2℃ | ||
− | * | + | * Single bus (I/O) communication |
− | * 2. | + | * 2.54 mm spacing pin |
− | == | + | ==How To== |
− | === | + | ===Connection=== |
− | * | + | *Connect to Tiny4412 SDK (1506) |
− | :: | + | ::GND: Ground |
− | ::VCC: | + | ::VCC: 5V |
− | :: | + | ::S: GPIO PIN1, this pin has to be connected to an interrupt pin. |
− | === | + | ===Code Sample in C Under Linux=== |
<syntaxhighlight lang="c"> | <syntaxhighlight lang="c"> | ||
#include <stdio.h> | #include <stdio.h> | ||
Line 89: | Line 551: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
− | === | + | ===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 97: | Line 559: | ||
make | make | ||
</syntaxhighlight> | </syntaxhighlight> | ||
− | + | Copy your compiled bin to your board and you are ready to go. | |
− | == | + | ==Resources== |
+ | --> |
Latest revision as of 15:50, 24 June 2016
Contents
1 Introduction
- The Matrix-Temperature_and_Humidity_Sensor module is used to detect temperature and humidity.
- It utilizes the DHT11 temperature and humidity sensor. Its humidity range is 20% - 80% and the accuracy is 5%. Its temperature range is 0℃ - 50℃ and the accuracy is ±2℃.
2 Features
- Humidity range: 20 - 80%RH, Temperature range 0 ~ 50℃
- Accuracy of humidity: +-5%RH, accuracy of temperature: +-2℃
- One wire communication
- 2.54 mm spacing pin
- PCB dimension (mm): 16 x 32
Pin Description:
Pin | Description |
S | GPIO |
V | Supply Voltage 5V |
G | Ground |
3 Basic Device Operation
The DHT11 module uses a simplified single-bus serial communication. DATA controls communication and synchronization between the microprocessor and DHT11. A data transfer takes 4ms. The data format contains an integer part and a decimal part. The basic operation is as follows:
- a transmission of 40 data, the high first-out
- data format: 8bit humidity integer data + 8bit the Humidity decimal data
- 8bit temperature integer data + 8bit fractional temperature data
- 8 bit parity bit
- If a transmission is successful the “8bit humidity integer data + 8bit humidity decimal data +8 bit temperature integer data + 8bit temperature fractional data” 8bit checksum is equal to the results of the last eight.
- After the user host (MCU) sends a signal DHT11 is converted from low-power mode to high-speed mode, until the host begins to signal the end. Then DHT11 sends a response signal to send 40bit data, and trigger a letter collection. If DHT11 doesn't receive a signal from the host it will not begin a letter collection. After the letter collection is done DHT11 will turn to low power mode.
4 Applications
4.1 Connect to NanoPi M1
Refer to the following connection diagram to connect the module to the NanoPi M1:
Connection Details:
Matrix-Temperature_and_Humidity_Sensor | 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:
Connection Details:
Matrix-Temperature_and_Humidity_Sensor | 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:
Connection Details:
Matrix-Temperature_and_Humidity_Sensor | 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-Temperature_and_Humidity_Sensor_NanoPC-T2
Connection Details:
Matrix-Temperature_and_Humidity_Sensor | 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-temp_humidity
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:
The humidity is 35000 The temperature is 26000
The module successfully read the environment's humidity and temperature values.
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-temperature_and_humidity_sensor". Here is its source code:
int main(int argc, char ** argv) { int ret = -1; int dhtTemp=0, dhtHdty=0, board; char modStr[BUF_SIZE]; int pin = GPIO_PIN(7); if ((board = boardInit()) < 0) { printf("Fail to init board\n"); return -1; } if (board == BOARD_NANOPI_T2) pin = GPIO_PIN(15); sprintf(modStr, "modprobe %s gpio=%d", DRIVER_MODULE, pintoGPIO(pin)); system(modStr); if ((ret = dht11Read(DHT_HUMIDITY, &dhtHdty)) != -1) { printf("The humidity is %d\n", dhtHdty); } else { printf("Faided to get humidity\n"); } if ((ret = dht11Read(DHT_TEMP, &dhtTemp)) != -1) { printf("The temperature is %d\n", dhtTemp); } else { printf("Faided to get temperature\n"); } system("rmmod "DRIVER_MODULE); return ret; }
For more details about this APIs called in this code sample refer to Matrix API reference manual
7 Resources
8 Update Log
8.1 Feb-23-2016
- Added the description for "NanoPi 2 branch" in Section 4
- Added Section 5: Connect to NanoPi 2
8.2 June-24-2016
- Re-organized and simplified wiki