家居智能系統(tǒng)中通常要使用紅外遙控去控制各種家電，如：電視、機(jī)頂盒、空調(diào)、電風(fēng)扇等，家電往往分布在家庭的各個(gè)不同房間，而紅外信號(hào)是無(wú)法穿墻去控制家電，怎么樣讓紅外信號(hào)“穿墻”，這是所有智能家居系統(tǒng)必須解決的問(wèn)題。
我的解決方案是使用NRF24L01無(wú)線通信模塊來(lái)進(jìn)行紅外信號(hào)“穿墻”，基本思路是：在家居智能主機(jī)上插上一片NRF24L01，而紅外穿墻控制分機(jī)同樣裝有NRF24L01，分機(jī)的功能是用于接收主機(jī)主機(jī)發(fā)來(lái)的紅外遙控信號(hào)，并將這個(gè)信號(hào)通過(guò)分機(jī)上的紅外發(fā)光二極管發(fā)送出去。
我們采集到的紅外遙控信號(hào)是一個(gè)時(shí)間序列，保存在一個(gè)uint16_t的數(shù)組中，這個(gè)數(shù)組根據(jù)遙控信號(hào)不同，從長(zhǎng)度為幾十到幾百不等，比如美的遙控信號(hào)的時(shí)間序列通常在200個(gè)左右。而NRF24L01每次能夠可靠傳輸?shù)臄?shù)據(jù)包最大是32個(gè)字節(jié)，要通過(guò)它傳輸幾百個(gè)字節(jié)的數(shù)據(jù)才能解決紅外信號(hào)穿墻的問(wèn)題，為此我設(shè)計(jì)了一個(gè)簡(jiǎn)單的流式傳輸協(xié)議來(lái)通過(guò)NRF24L01進(jìn)行可靠數(shù)據(jù)的傳輸，相應(yīng)的函數(shù)原型：
uint8_t NRF24L01_Send(uint8_t *buf, uint16_t len);
uint16_t NRF24L01_Recv(uint8_t *buf, uint16_t len);
由于這兩個(gè)函數(shù)傳輸?shù)氖莡int8_t的數(shù)組，而紅外信號(hào)的時(shí)間序列是uint16_t的數(shù)組，為了將信號(hào)通過(guò)無(wú)線模塊進(jìn)行傳輸，我還特地設(shè)計(jì)了兩個(gè)轉(zhuǎn)換函數(shù)：
void word2ByteArray(uint16_t *buf, uint16_t len, uint8_t *bBuf);
void byte2WordArray(uint8_t *bBuf, uint16_t bLen, uint16_t *buf);
有了上述一些基礎(chǔ)準(zhǔn)備，接下來(lái)實(shí)現(xiàn)紅外穿墻控制就水到渠成了。
為了驗(yàn)證我的這個(gè)方案，特地設(shè)計(jì)了一個(gè)模擬的家居智能“主機(jī)”，這個(gè)主機(jī)功能非常簡(jiǎn)單：接收來(lái)自串口的輸入，如果串口輸入1，則向分機(jī)發(fā)送開空調(diào)的紅外信號(hào)，讓隔壁的空調(diào)打開；如果輸入0，則向分機(jī)發(fā)送關(guān)空調(diào)的紅外信號(hào)，讓隔壁的空調(diào)關(guān)機(jī)。在軟件包的“Projects\NRF24L01-SendLong”文件夾包含了這個(gè)程序的完整工程，可以直接編譯、燒寫和調(diào)試。程序代碼如下：
#include "WProgram.h"
#include "24l01.h"
#include "stdlib_ex.h"
//美的空調(diào)：開
uint16_t rawData_1[] =
{4486,4428,590,1604,590,534,563,1605,591,1603,592,533,563,535,563,1604,591,535,563,534,564,1606,589,
534,563,535,563,1604,590,1603,592,535,563,1604,591,1607,588,535,563,1605,590,1607,588,1604,591,1632,
564,1602,593,1605,591,534,563,1602,593,534,563,534,563,534,563,535,563,534,563,534,563,1604,591,534,
563,1632,563,534,564,1604,590,1605,590,534,563,534,564,534,563,1605,591,533,563,1604,591,535,563,534,
563,1605,590,1604,592,5263,4512,4427,592,1602,593,534,563,1602,593,1632,563,535,563,534,563,1605,
590,535,564,533,563,1607,589,534,563,534,563,1604,592,1602,593,534,563,1604,591,1630,564,534,563,
1631,564,1604,591,1604,592,1603,592,1604,591,1633,563,534,563,1604,592,534,563,535,563,510,587,534,
563,534,564,510,587,1630,565,510,587,1631,564,511,586,1603,592,1604,591,511,587,511,587,509,588,1605,
590,510,587,1603,593,510,587,511,587,1603,592,1604,591};
//美的空調(diào)：關(guān)
uint16_t rawData_0[] =
{4464,4451,567,1628,567,532,565,1628,567,1629,567,531,565,532,567,1626,568,531,566,532,565,1628,568,
532,565,532,566,1627,568,1630,565,532,566,1627,568,532,566,1629,566,1628,567,1629,567,1628,567,532,
565,1629,567,1627,568,1628,567,531,567,531,565,532,566,532,565,1627,568,531,566,532,566,1628,567,
1629,566,1627,568,533,565,532,565,532,566,531,566,532,566,531,565,533,565,532,565,1627,568,1629,567,
1629,567,1628,567,1627,568,5286,4489,4452,567,1629,566,532,566,1628,568,1627,568,531,566,531,566,
1628,568,530,566,531,565,1629,567,532,565,532,565,1630,566,1629,567,532,565,1628,567,533,565,1629,
567,1628,567,1628,592,1604,590,508,577,1616,577,1620,590,1603,567,533,589,508,589,509,589,508,589,
1603,592,508,590,507,590,1603,591,1633,562,1543,652,509,589,509,588,509,589,508,590,508,589,508,590,
507,589,508,589,1605,590,1604,591,1604,591,1604,592,1604,592};
uint16_t len1 = sizeof(rawData_1)/sizeof(uint16_t);
uint16_t len0 = sizeof(rawData_0)/sizeof(uint16_t);
void setup()
{
//初始化Rainbow
boardInit();
//初始化默認(rèn)串口
Serial.begin();
//初始化無(wú)線通信模塊
NRF24L01_Init();
Serial.println("NRF24L01-SendLong start...");
}
void loop()
{
uint8_t *bRawData;
if(Serial.available())
{
switch(Serial.read())
{
case 0x30:
bRawData = new uint8_t[2*len0];
word2ByteArray(rawData_0, len0, bRawData);
//關(guān)空調(diào)
if(NRF24L01_Send(bRawData, 2*len0))
Serial.println("Close conditioner...");
delete []bRawData;
break;
case 0x31:
bRawData = new uint8_t[2*len1];
word2ByteArray(rawData_1, len1, bRawData);
//開空調(diào)
if(NRF24L01_Send(bRawData, 2*len1))
Serial.println("Open conditioner...");
delete []bRawData;
break;
}
}
}
int main()
{
setup();
while(1) loop();
}
紅外信號(hào)穿墻控制分機(jī)的功能則非常簡(jiǎn)單，僅僅就是接收NRF24L01發(fā)來(lái)的紅外遙控時(shí)間序列，然后通過(guò)紅外發(fā)光二極管發(fā)送出去。在軟件包的“Projects\NRF24L01-RecvLong”文件夾包含了紅外穿墻分機(jī)的完整工程，可以直接編譯、燒寫和調(diào)試。程序代碼如下：
#include "WProgram.h"
#include "24l01.h"
#include "stdlib_ex.h"
#include "IRRemote.h"
//接收緩沖的大小
#define RECV_BUF_LEN 800
uint8_t buf[RECV_BUF_LEN];
//定義紅外發(fā)射對(duì)象，紅外發(fā)光二極管接到TIM2的CH1，即：PB8
IRSend irSend;
void setup()
{
//初始化Rainbow
boardInit();
//初始化默認(rèn)串口
Serial.begin();
//初始化無(wú)線通信模塊
NRF24L01_Init();
//用38K的載波進(jìn)行調(diào)制
irSend.enableIROut(38);
Serial.println("NRF24L01-RecvLong start...");
}
void loop()
{
//接收到對(duì)方發(fā)來(lái)的數(shù)據(jù)
uint16_t wBuf[RECV_BUF_LEN/2];
uint16_t len = NRF24L01_Recv(buf, RECV_BUF_LEN);
if(len > 0)
{
//收到的byte數(shù)組，轉(zhuǎn)化成紅外遙控的uint16_t數(shù)組
byte2WordArray(buf, len, wBuf);
irSend.sendRaw(wBuf, len/2);
}
}
int main()
{
setup();
while(1) loop();
}