void clock_init(void){
jiffies = 0;
TMOD=0x02;
TH0=TL0=0x0ce;//12M,50us
//TH0=TL0=0x7a;//16M
//TH0=TL0=0x75;//16.59M
//TH0=TL0=0x72;//17M
//TH0=TL0=0x37;//24M
//TH0=TL0=0x47;//22.1844M, 100us
//TH0=TL0=0xa3;//22.1844M, 50us
EA=1;
ET0=1;

TR0=1;
}

void clock_init_again(void){

TMOD=0x02;
TH0=0x0ce;//12M,50us
TL0=T0_last;
//TH0=TL0=0x7a;//16M
//TH0=TL0=0x75;//16.59M
//TH0=TL0=0x72;//17M
//TH0=TL0=0x37;//24M
//TH0=TL0=0x47;//22.1844M, 100us
//TH0=TL0=0xa3;//22.1844M, 50us
EA=1;
ET0=1;
jiffies=0;
TR0=1;
}

void init_serialcomm(void)
{
SCON = 0x50; //SCON: serail mode 1, 8-bit UART, enable ucvr
TMOD |= 0x20; //TMOD: timer 1, mode 2, 8-bit reload
PCON |= 0x80; //SMOD=1;
TH1 = 0x0e6; //Baud:2400 fosc=11.0592MHz :f4
TL1 = 0x0e6;
//IE |= 0x90; //Enable Serial Interrupt
TR1 = 1; // timer 1 run
RI=0;
TI=1;
}

void serial_out(char d){
while(!TI);
TI=0;
SBUF=(d);
}

void send_string_com(char *str,int strlen)//串口程序
{ char sum;

int k=0;
serial_out(02);
do
{ sum^=*(str+k);
serial_out(*(str + k));
k++;
} while(k < strlen);
serial_out(sum);
serial_out(03);
}

//等待指定長(zhǎng)度的串行數(shù)據(jù)到達(dá),超時(shí)值為每?jī)蓚€(gè)字節(jié)之間的間隔時(shí)間而非等待整個(gè)串的時(shí)間.
//超時(shí)單位為time_out * 100uS
bit wait_serial(unsigned char *p, unsigned char len, unsigned char time_out){
unsigned int time=jiffies;
unsigned char n=0;
do{
if (RI){
p[n++]=SBUF;
RI=0;
if(n==len)
return 0;
time=jiffies;
}
}while(jiffies-time < time_out);
return 1;
}

sys_init(){
clock_init();
init_serialcomm();
}

//=============================================================
//發(fā)送程序 開(kāi)始
//=============================================================

#define PULS_0_WIDTH 8//低電平脈寬
#define PULS_1_WIDTH 16//高電平脈寬
#define PULS_HEAD_WIDTH 8//前導(dǎo)信號(hào)脈寬
#define PULS_START_WIDTH 24//引導(dǎo)信號(hào)脈寬
#define PULS_STOP_WIDTH 8//結(jié)束碼脈寬

#define PULS_HEAD_COUNTS 16//前導(dǎo)信號(hào)長(zhǎng)度

unsigned char send_buf[16];
#define send_byts send_buf[0]//剩余字節(jié)數(shù),發(fā)送完后為0
unsigned char sending_byte;//當(dāng)前正在發(fā)送的字節(jié)
unsigned char send_byte_p;//已發(fā)送字節(jié)數(shù)(含正在發(fā)送的字節(jié))
unsigned char send_bit_p;//當(dāng)前正在發(fā)送的字節(jié)已發(fā)送位數(shù)(含正在發(fā)送的位)

#define SEND_PROGRESSING 0x41
#define SEND_FAILED 0x21
#define SEND_SUCCESS 0x31
unsigned char send_stat = 0;//發(fā)送程序當(dāng)前狀態(tài),為0時(shí)正常
unsigned char head_counts;//前導(dǎo)信號(hào)計(jì)數(shù)器(包括引導(dǎo)信號(hào))

void start_send(){
send_byte_p = 0;
send_bit_p = 0;
send_stat = SEND_PROGRESSING;
head_counts = 16;
}

#define START_SEND(byts) send_buf[0]=byts;send_byts=byts;start_send()

//發(fā)送前應(yīng)清除send_byte_p,send_bit_p,send_stat,并設(shè)置send_byts
//發(fā)送過(guò)程中可根據(jù)send_byts的值得到剩余字節(jié)數(shù),根據(jù)send_byte_p的值得到已發(fā)送字節(jié)數(shù).注意,將正在發(fā)送的字節(jié)當(dāng)作已發(fā)送完畢.
//發(fā)送過(guò)程中可根據(jù)send_stat的值得到發(fā)送狀態(tài).
//發(fā)送完成后,send_byts和send_bit_p的值都為0.
#define SEND_PULS(x) w_data=send_busy=(x>>1)
void send(){
//下面兩行在wirless()中已經(jīng)執(zhí)行過(guò)了,所以無(wú)需寫上
//if (send_stat != SEND_PROGRESSING)
//return;

if (!send_busy){
if(send_byts || send_bit_p){
if (head_counts){
head_counts--;
if(head_counts)
SEND_PULS(PULS_HEAD_WIDTH);
else
SEND_PULS(PULS_START_WIDTH);
}else{
if (send_bit_p == 0){
sending_byte = send_buf[send_byte_p];
send_byte_p++;
send_byts--;
send_bit_p = 8;
}

if(sending_byte & 0x80){
SEND_PULS(PULS_1_WIDTH);
}else{
SEND_PULS(PULS_0_WIDTH);
}

sending_byte <<= 1;
send_bit_p--;
}
}else{
SEND_PULS(PULS_STOP_WIDTH);
send_stat = SEND_SUCCESS;
}
}
return;
}
//=============================================================
//發(fā)送程序 結(jié)束
//=============================================================

//=============================================================
//接收程序 開(kāi)始
//=============================================================

unsigned char recv_buf[16];
#define recv_byts recv_buf[0]//應(yīng)收到字節(jié)數(shù),由每個(gè)包的第一個(gè)字節(jié)指定
unsigned char recving_byte;//當(dāng)前正在接收的字節(jié)
unsigned char recv_byte_p;//已收到字節(jié)數(shù)(不含正在接收的字節(jié))
unsigned char recv_bit_p;//當(dāng)前正在接收的字節(jié)等待接收位數(shù)(不含正在接收的位)

#define RECV_FAILED 0x31
#define RECV_SUCCESS 0x41

unsigned char recv_stat = 0; //接收程序當(dāng)前狀態(tài),為0時(shí)正常
unsigned char recv_step = 0;//引導(dǎo)脈沖標(biāo)志,為0時(shí)等待引導(dǎo),為1時(shí)等待數(shù)據(jù)

#define TEST_PULS(puls_in, puls_type) (puls_in > puls_type - PULS_0_WIDTH / 2 && puls_in < puls_type + PULS_0_WIDTH / 2)

#define HEAD_NEED_RECIVED 8
void recv(){
unsigned puls_width;

if ((recv_stat == RECV_SUCCESS) || !w_data)
return;

puls_width = w_data;
w_data = 0;

#if 0//輸出脈寬
serial_out(puls_width);
//printhex(puls_width);
#endif

if (recv_step < HEAD_NEED_RECIVED){
if(TEST_PULS(puls_width, PULS_HEAD_WIDTH)){
recv_step++;
}else{
recv_step = 0;
}
}else if (recv_step == HEAD_NEED_RECIVED){
if(TEST_PULS(puls_width, PULS_START_WIDTH)){
serial_out(0xbb);
recv_byte_p = 0;
recv_bit_p = 8;
recv_stat = 0;
recv_step++;
}else{
if(!TEST_PULS(puls_width, PULS_HEAD_WIDTH)){
recv_step = 0;
}
}
}else{
//serial_out(puls_width);
recving_byte <<= 1;
if(TEST_PULS(puls_width, PULS_0_WIDTH)){
recving_byte &= 0xfe;
}else if(TEST_PULS(puls_width, PULS_1_WIDTH)){
recving_byte |= 1;
}else{
serial_out(puls_width);
recv_step = 0;
serial_out(0xaa);
return;
}