我想用 mbed (LPC1768) 创建一个低功耗应用程序,并且一直在学习 Jim Hamblen 的教程:https ://mbed.org/cookbook/Power-Management和http://mbed.org/users/no2chem/笔记本/mbed-power-controlconsumption/
我能够通过 GPIO 中断、UART 中断和 Ticker 从 Sleep() 中唤醒 mbed。我使用 PowerControl 库。
这是我的代码:
#include "mbed.h"
#include "PowerControl/PowerControl.h"
#include "PowerControl/EthernetPowerControl.h"
// Need PowerControl *.h files from this URL
// http://mbed.org/users/no2chem/notebook/mbed-power-controlconsumption/
// Function to power down magic USB interface chip with new firmware
#define USR_POWERDOWN (0x104)
int semihost_powerdown() {
uint32_t arg;
return __semihost(USR_POWERDOWN, &arg);
}
DigitalOut myled1(LED1);
DigitalOut myled2(LED2);
DigitalOut myled3(LED3);
DigitalOut myled4(LED4);
bool rx_uart_irq = false;
Serial device(p28, p27); // tx, rx
InterruptIn button(p5);
// Circular buffers for serial TX and RX data - used by interrupt routines
const int buffer_size = 255;
// might need to increase buffer size for high baud rates
char tx_buffer[buffer_size];
char rx_buffer[buffer_size];
// Circular buffer pointers
// volatile makes read-modify-write atomic
volatile int tx_in=0;
volatile int tx_out=0;
volatile int rx_in=0;
volatile int rx_out=0;
// Line buffers for sprintf and sscanf
char tx_line[80];
char rx_line[80];
void Rx_interrupt();
void blink() {
myled2 = !myled2;
}
int main() {
//int result;
device.baud(9600);
device.attach(&Rx_interrupt, Serial::RxIrq);
// Normal mbed power level for this setup is around 690mW
// assuming 5V used on Vin pin
// If you don't need networking...
// Power down Ethernet interface - saves around 175mW
// Also need to unplug network cable - just a cable sucks power
PHY_PowerDown();
myled2 = 0;
// If you don't need the PC host USB interface....
// Power down magic USB interface chip - saves around 150mW
// Needs new firmware (URL below) and USB cable not connected
// http://mbed.org/users/simon/notebook/interface-powerdown/
// Supply power to mbed using Vin pin
//result = semihost_powerdown();
// Power consumption is now around half
// Turn off clock enables on unused I/O Peripherals (UARTs, Timers, PWM, SPI, CAN, I2C, A/D...)
// To save just a tiny bit more power - most are already off by default in this short code example
// See PowerControl.h for I/O device bit assignments
// Don't turn off GPIO - it is needed to blink the LEDs
Peripheral_PowerDown( ~( LPC1768_PCONP_PCUART0 |
LPC1768_PCONP_PCUART2 |
0));
// use Ticker interrupt and Sleep instead of a wait for time delay - saves up to 70mW
// Sleep halts and waits for an interrupt instead of executing instructions
// power is saved by not constantly fetching and decoding instructions
// Exact power level reduction depends on the amount of time spent in Sleep mode
//blinker.attach(&blink, 0.05);
//button.rise(&blink);
while (1) {
myled1 = 0;
printf("bye\n");
Sleep();
if(rx_uart_irq == true) {
printf("wake from uart irq\n");
}
myled1 = 1;
}
}
// Interupt Routine to read in data from serial port
void Rx_interrupt() {
myled2 = !myled2;
rx_uart_irq = true;
uint32_t IRR0= LPC_UART2->IIR;
while ((device.readable()) && (((rx_in + 1) % buffer_size) != rx_out)) {
rx_buffer[rx_in] = LPC_UART2->RBR;
rx_in = (rx_in + 1) % buffer_size;
}
}
这是问题所在:添加 mbed-rtos 库时,Sleep() 不会使 mbed 进入睡眠状态。即使我不使用 rtos 库中的任何函数调用, Sleep() 也不起作用。
我的解释:可能 rtos 有一个在后台运行的计时器,它时不时地产生一个中断。(但这有点没有意义,因为我没有使用 rtos 库中的任何函数或对象)
我的问题:
有没有人让 Sleep() 函数与 rtos 一起工作?如果是,请指出正确的方向,或者如果您有解决方案,请分享。