Difference between revisions of "Matrix - Potentiometer"
(→硬件连接) |
(→Update Log) |
||
| (2 intermediate revisions by the same user not shown) | |||
| Line 99: | Line 99: | ||
|} | |} | ||
| − | == | + | ==Compile & Run Test Program== |
| − | + | Boot your ARM board with Debian and copy the matrix code: | |
<syntaxhighlight lang="bash"> | <syntaxhighlight lang="bash"> | ||
$ apt-get update && apt-get install git | $ apt-get update && apt-get install git | ||
$ git clone https://github.com/friendlyarm/matrix.git | $ git clone https://github.com/friendlyarm/matrix.git | ||
</syntaxhighlight> | </syntaxhighlight> | ||
| − | + | If your cloning is done successfully a "matrix" directory will be generated. | |
| − | + | Compile and install Matrix: | |
<syntaxhighlight lang="bash"> | <syntaxhighlight lang="bash"> | ||
$ cd matrix | $ cd matrix | ||
| Line 113: | Line 113: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
| − | + | Run test program: | |
<syntaxhighlight lang="bash"> | <syntaxhighlight lang="bash"> | ||
$ matrix-adc | $ matrix-adc | ||
</syntaxhighlight> | </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"> | <syntaxhighlight lang="bash"> | ||
The channel0 value is 2460 | The channel0 value is 2460 | ||
</syntaxhighlight> | </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-analog_to_digital_converter". Here is its source code: | |
<syntaxhighlight lang="c"> | <syntaxhighlight lang="c"> | ||
int main(int argc, char ** argv) | int main(int argc, char ** argv) | ||
| Line 153: | Line 153: | ||
} | } | ||
</syntaxhighlight> | </syntaxhighlight> | ||
| − | + | For more details about this APIs called in this code sample refer to [[Matrix API reference manual]] <br> | |
==Resources== | ==Resources== | ||
| Line 278: | Line 278: | ||
===Feb-24-2016=== | ===Feb-24-2016=== | ||
* Added link to the Chinese version | * Added link to the Chinese version | ||
| + | ===June-23-2016=== | ||
| + | * Re-organized and simplified wiki | ||
Latest revision as of 14:27, 23 June 2016
Contents
1 Introduction
- The Matrix-Potentiometer module is a Potentiometer module. It can be used in audio control, motion control, transducers, computation and etc.
- 3 Pin 2.54mm spacing pin header, V is supply voltage, G is ground and S is output analog signal. Users can convert output analog signals to digital signals via ADC conversion.
- Output Voltage: 0 ~ Vcc
2 Features
- GPIO
- Small
- 2.54mm spacing pin header
- PCB Dimension(mm): 8 x 24
- Pin Description:
| Pin | Description |
| S | Analog GPIO |
| V | Supply Voltage 5V |
| G | Ground |
3 Basic Device Operation
- A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider.If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat.
- This module mainly contains a potentiometer where the resistance changes with changes between the contact and one end terminal.
4 Applications
The Matrix-Potentiometer module outputs analog signals which can be converted to digital signals through an ADC converter e.g. the Matrix-Analog_to_Digital_Converter module.
For more details about the Matrix-Analog_to_Digital_Converter module refer to wiki:Matrix-Analog_to_Digital_Converter。
4.1 Connect to NanoPi M1
Refer to the following connection diagram to connect the module to the NanoPi M1:
Connection Details:
| Matrix-Potentiometer | |
| GND | NanoPi M1 Pin9 |
| 5V | NanoPi M1 Pin2 |
| S | Matrix-Analog_to_Digital_Converter A0 |
4.2 Connect to NanoPi 2
Refer to the following connection diagram to connect the module to the NanoPi 2:
Connection Details:
| Matrix-Potentiometer | |
| GND | NanoPi 2 Pin9 |
| 5V | NanoPi 2 Pin2 |
| S | Matrix-Analog_to_Digital_Converter A0 |
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-Potentiometer | |
| GND | NanoPi M2 Pin9 |
| 5V | NanoPi M2 Pin2 |
| S | Matrix-Analog_to_Digital_Converter A0 |
4.4 Connect to NanoPC-T2
Refer to the following connection diagram to connect the module to the NanoPC-T2:
Matrix-Potentiometer_NanoPC-T2
Connection Details:
| Matrix-Potentiometer | |
| GND | NanoPC-T2 USB Host GND |
| 5V | NanoPC-T2 USB Host 5V |
| S | Matrix-Analog_to_Digital_Converter A0 |
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-adcNote: 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 channel0 value is 24606 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-analog_to_digital_converter". Here is its source code:
int main(int argc, char ** argv) { int i = 0; int value = 0; int channel = 0; if (boardInit() < 0) { printf("Fail to init board\n"); return -1; } if (argc == 2) channel = atoi(argv[1]); system("modprobe "DRIVER_MODULE); signal(SIGINT, intHandler); for (i=0; i<ADC_READ_TIMES; i++) { if (pcf8591Read(channel, &value) != -1) { printf("The channel%d value is %d\n", channel, value); } else { printf("Fail to get channel%d value\n", channel); } } system("rmmod "DRIVER_MODULE); return 0; }
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-24-2016
- Added link to the Chinese version
8.2 June-23-2016
- Re-organized and simplified wiki
