Difference between revisions of "Matrix - LED"
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一个直径为5mm的LED，3-Pin 2.54mm排针，V接电源，G接地，S信号通过一个三极管放大控制LED的导通或关闭。您可以向S输出静态的高低电平信号，也可以输出变化的PWM信号，信号电平可以是3.3V或5V。当您向S输出高电平时LED以最大亮度发光，低电平就完全熄灭，可变占空比的PWM信号可以调节发光的亮度。我们提供红、绿、白三种颜色的配件供您购买。 | 一个直径为5mm的LED，3-Pin 2.54mm排针，V接电源，G接地，S信号通过一个三极管放大控制LED的导通或关闭。您可以向S输出静态的高低电平信号，也可以输出变化的PWM信号，信号电平可以是3.3V或5V。当您向S输出高电平时LED以最大亮度发光，低电平就完全熄灭，可变占空比的PWM信号可以调节发光的亮度。我们提供红、绿、白三种颜色的配件供您购买。 | ||
| − | == | + | ==Features== |
| − | * | + | * GPIO/PWM interface, 3.3/5V, PWM brightness control |
| − | * | + | * Tiny, easy to be used in various situations |
| − | * 2. | + | * 2.54mm spacing pin |
==How To== | ==How To== | ||
Revision as of 07:28, 7 August 2015
Contents
1 Introduction
一个直径为5mm的LED，3-Pin 2.54mm排针，V接电源，G接地，S信号通过一个三极管放大控制LED的导通或关闭。您可以向S输出静态的高低电平信号，也可以输出变化的PWM信号，信号电平可以是3.3V或5V。当您向S输出高电平时LED以最大亮度发光，低电平就完全熄灭，可变占空比的PWM信号可以调节发光的亮度。我们提供红、绿、白三种颜色的配件供您购买。
2 Features
- GPIO/PWM interface, 3.3/5V, PWM brightness control
- Tiny, easy to be used in various situations
- 2.54mm spacing pin
3 How To
3.1 Connection
- Connect to Tiny4412 SDK (1506)
- Connect the module's pin S to GPIO PIN1, V to 5V and G grounded
3.2 Code Sample in C Under Linux
#include <stdio.h> #include <unistd.h> #include "libfahw.h" #define LED_BLINK_TIMES 10 int main(int argc, char ** argv) { int ledPin = TINY4412_GPIO_PIN1; int i = 0; int ret = -1; if ((ret = exportGPIOPin(ledPin)) == -1) { printf("exportGPIOPin(%d) failed\n", ledPin); } if ((ret = setGPIODirection(ledPin, GPIO_OUT)) == -1) { printf("setGPIODirection(%d) failed\n", ledPin); } for (i = 0; i < LED_BLINK_TIMES; i++) { if (i % 2) { ret = setGPIOValue(ledPin, GPIO_HIGH); } else { ret = setGPIOValue(ledPin, GPIO_LOW); } if (ret == -1) { printf("setGPIOValue(%d) failed\n", ledPin); } printf("LED blinking times %d\n", i); sleep(1); } unexportGPIOPin(ledPin); return 0; }
3.3 Compile and Run
git clone http://github.com/friendlyarm/fa-hardware.git cd fa-hardware cd demo cd matrix-led make
Copy your compiled bin to your board and you are ready to go.
