提示1：锐米所有 LoRa 产品严格遵循国际标准的 LoRaWAN 协议。
提示2：您可以免费复制，修改和商用本项目，请注明锐米原创。
提示3：如果您有其他 LoRa 需求或建议，欢迎联系锐米 support@rimelink.com
LoRa 模组入网后将自动休眠，Arduino 上电后休眠，将电流表串联在上述电路中测量值为 1.4uA。当 Arduino 响应按钮中断时电流增大，随后又进入休眠。
ArduinoLoRaLowPower_INT1.4uA
超过 80% 的 LoRa 终端将由电池供电，这样一来，低功耗将是一个核心的技术挑战，一旦电能耗尽设备将“罢工”，在某些场合电能意味着 LoRa 终端的寿命。
ArduinoLoRa+ 是锐米推出的低成本快速开发 LoRa 终端方案，基于外部中断唤醒工作，它能达到行业第一的低功耗(1.4uA)，最大延长电池续航能力。
下面，逐步解密 ArduinoLoRa+ 中断唤醒低功耗是如何实现的。
LoRa 开发板 x 1 采购链接
按钮 x 1 采购链接
电池盒 x 1 采购链接
7 号电池 x 2 采购链接
鳄鱼夹 x 2 采购链接
杜邦线 x 10 采购链接
Arduino IDE 下载链接
下载器 采购链接
数字万用表 采购链接
按下表连接 LoRa 开发板 和 下载烧录器
| LoRa 开发板 | 杜邦线 | 下载烧录器 |
|---|---|---|
| VCC | 红 | 3.3 |
| GND | 黑 | GND |
| RX | 绿 | TXD |
| TX | 黄 | RXD |
| DTR | 棕 | DTR |
#include <avr/sleep.h>
/*
* Example code to demonstrate the sleep functions in a Arduino.
*
* use a pull up resistor on pin 2 to 5V.
* and ground pin 2 momentary to wake it up again.
*
* When awake, the arduino will run the ledPin_blink code
*/
const int ledPin = 13; // ledPin connected to digital pin 13
const int wakePin = 2; // active LOW, ground this pin momentary to wake up
/* here we put the arduino to sleep */
void sleepNow()
{
/* Now is the time to set the sleep mode. In the Atmega8 datasheet
* https://www.atmel.com/dyn/resources/prod_documents/doc2486.pdf on page 35
* there is a list of sleep modes which explains which clocks and
* wake up sources are available in which sleep modus.
*
* In the avr/sleep.h file, the call names of these sleep modus are to be found:
*
* The 5 different modes are:
* SLEEP_MODE_IDLE -the least power savings
* SLEEP_MODE_ADC
* SLEEP_MODE_PWR_SAVE
* SLEEP_MODE_STANDBY
* SLEEP_MODE_PWR_DOWN -the most power savings
*
* For now, we want as much power savings as possible,
* so we choose the according sleep modus: SLEEP_MODE_PWR_DOWN
*
*/
set_sleep_mode(SLEEP_MODE_PWR_DOWN); // sleep mode is set here
sleep_enable(); // enables the sleep bit in the mcucr register so sleep is possible. just a safety pin
/* Now is time to enable a interrupt. we do it here so an
* accidentally pushed interrupt button doesn't interrupt
* our running program. if you want to be able to run
* interrupt code besides the sleep function, place it in
* setup() for example.
*
* In the function call attachInterrupt(A, B, C)
* A can be either 0 or 1 for interrupts on pin 2 or 3.
*
* B Name of a function you want to execute at interrupt for A.
*
* C Trigger mode of the interrupt pin. can be:
* LOW a low level triggers
* CHANGE a change in level triggers
* RISING a rising edge of a level triggers
* FALLING a falling edge of a level triggers
*
* In all but the IDLE sleep modes only LOW can be used.
*/
attachInterrupt(0, wakeUpNow, FALLING); // use interrupt 0 (pin 2) and run function wakeUpNow when pin 2 gets LOW
sleep_mode(); // here the device is actually put to sleep!!
/* THE PROGRAM CONTINUES FROM HERE AFTER WAKING UP */
sleep_disable(); // first thing after waking from sleep: disable sleep...
detachInterrupt(0); // disables interrupt 0 on pin 2 so the wakeUpNow code will not be executed during normal running time.
}
/* here the interrupt is handledPin after wakeup */
void wakeUpNow()
{
// execute code here after wake-up before returning to the loop() function
// timers and code using timers (serial.print and more...) will not work here.
}
void flash()
{
pinMode(ledPin, OUTPUT);
digitalWrite(ledPin, HIGH);
delay(50);
digitalWrite(ledPin, LOW);
delay(50);
pinMode(ledPin, INPUT);
}
void setup()
{
ADCSRA = 0; // disable ADC
pinMode(wakePin, INPUT);
digitalWrite (wakePin, HIGH); // enable pull-up
}
void loop()
{
flash();
sleepNow();
}
如下图所示，使用杜邦线连接 LoRa 开发板和按钮，并使用电池供电。
