EV1527解码，抗干扰，自适应.....
EV1527解码，我也贡献一个，抗干扰，自适应, 经测试比买的解码成功率高，具体多少没计算，通过示波器看到；
/*
中断处理函数 、每次中断查询一下电平；
手册16个CLK（一个数据位）的时间是
最大4.24ms(4240us)/16= 265us; 最小230us/16=14us; 分频时间是4us；
；
同步头高电平至少4个时钟；识别同步头分2步
第一步高电平时间大于等于40us，小于265*4*1.2 = 1060*1.2=1270us；
第二步 低电平时间是高电平时间的31倍，留20%余量26倍-36倍之间；
计算电平时间 （高电平时间 + 低电平时间） / 32 ;
数据宽时间要在这个数值的 正负20% 之间
*/
INTERRUPT_HANDLER(EXTI_PORTA_IRQHandler, 3)
{
static U16 data_h_time; //
static U16 data_l_time; //
static U16 bit_time_min;
static U16 bit_time_max;
static U8 decode_KEY;
static U32 decode_ID;
U16 temp;
static U8 ev1527_rx_last;
U16 ev1527_new_time;
disableInterrupts();
ev1527_new_time = (uint16_t)TIM2->CNTRH << 8;
ev1527_new_time |= (uint16_t)(TIM2->CNTRL);
if(EV1527_RX) //接收编码高电平
{
if(ev1527_rx_last==0) //上次是低电平，有跳变
{
EV1527_COUNT_CLEAR;
if(ev1527_decode_state>sync_h)
{
str_ev1527_data.l_data[str_ev1527_data.l_data_write] = ev1527_new_time;
str_ev1527_data.l_data_write = (str_ev1527_data.l_data_write + 1) % EV1527_DATA_TIME_NUM;
switch(ev1527_decode_state)
{
case sync_l:{
temp = str_ev1527_data.l_data[str_ev1527_data.l_data_read] / str_ev1527_data.h_data[str_ev1527_data.h_data_read];
if((temp >= SYNC_RATIO_MIN) && (temp <= SYNC_RATIO_MAX))
{
temp = str_ev1527_data.l_data[str_ev1527_data.l_data_read] + str_ev1527_data.h_data[str_ev1527_data.h_data_read];
str_ev1527_data.h_data_read = (str_ev1527_data.h_data_read + 1) % EV1527_DATA_TIME_NUM;
str_ev1527_data.l_data_read = (str_ev1527_data.l_data_read + 1) % EV1527_DATA_TIME_NUM;
bit_time_min = temp / 9;
bit_time_max = temp / 7;
decode_ID = 0;
decode_KEY = 0;
data_h_time = 0;
data_l_time = 0;
ev1527_decode_state = chipid_0l;
}
else
{
ev1527_decode_state = sync_h;
}
}break;
case chipid_0l:
case chipid_1l:
case chipid_2l:
case chipid_3l:
case chipid_4l:
case chipid_5l:
case chipid_6l:
case chipid_7l:
case chipid_8l:
case chipid_9l:
case chipid_10l:
case chipid_11l:
case chipid_12l:
case chipid_13l:
case chipid_14l:
case chipid_15l:
case chipid_16l:
case chipid_17l:
case chipid_18l:
case chipid_19l:
{
data_h_time += str_ev1527_data.h_data[str_ev1527_data.h_data_read];
data_l_time += str_ev1527_data.l_data[str_ev1527_data.l_data_read];
str_ev1527_data.l_data_read = (str_ev1527_data.l_data_read + 1) % EV1527_DATA_TIME_NUM;
str_ev1527_data.h_data_read = (str_ev1527_data.h_data_read + 1) % EV1527_DATA_TIME_NUM;
temp = data_h_time + data_l_time;
if(temp >= bit_time_min)
{
if(temp <= bit_time_max)
{
if(data_h_time > data_l_time)
{
decode_ID |= 0x01;
}
decode_ID <<= 1;
ev1527_decode_state++;
data_h_time = 0;
data_l_time = 0;
}
else
{
ev1527_decode_state = sync_h;
}
}
}break;
case data_0l:
case data_1l:
case data_2l:
case data_3l:
{
data_h_time += str_ev1527_data.h_data[str_ev1527_data.h_data_read];
data_l_time += str_ev1527_data.l_data[str_ev1527_data.l_data_read];
str_ev1527_data.l_data_read = (str_ev1527_data.l_data_read + 1) % EV1527_DATA_TIME_NUM;
str_ev1527_data.h_data_read = (str_ev1527_data.h_data_read + 1) % EV1527_DATA_TIME_NUM;
temp = data_h_time + data_l_time;
if(temp >= bit_time_min)
{
if(temp <= bit_time_max)
{
if(data_h_time > data_l_time)
{
decode_KEY |= 0x08;
}
if(ev1527_decode_state == data_3l)
{
ev1527_chip_ID = decode_ID;
ev1527_chip_key = decode_KEY;
ev1527_new_sms = 1;
LED_ON(LED_01);
ev1527_decode_state = sync_h;
}
else
{
decode_KEY >>= 1;
ev1527_decode_state++;
}
data_h_time = 0;
data_l_time = 0;
}
else
{
ev1527_decode_state = sync_h;
}
}
}break;
}
}
}
ev1527_rx_last = 1;
}
else //接收编码低电平
{
if(ev1527_rx_last) //上次是高电平，有跳变
{
EV1527_COUNT_CLEAR;
if(ev1527_decode_state == sync_h)
{
if((ev1527_new_time >= SYNC_H_TIME_MIN) && (ev1527_new_time <= SYNC_H_TIME_MAX))
{
str_ev1527_data.l_data_read = str_ev1527_data.l_data_write=0;
str_ev1527_data.h_data_read = str_ev1527_data.h_data_write=0;
str_ev1527_data.h_data[str_ev1527_data.h_data_write] = ev1527_new_time;
str_ev1527_data.h_data_write = (str_ev1527_data.h_data_write + 1) % EV1527_DATA_TIME_NUM;
ev1527_decode_state = sync_l;
}
}
else
{
str_ev1527_data.h_data[str_ev1527_data.h_data_write] = ev1527_new_time;
str_ev1527_data.h_data_write = (str_ev1527_data.h_data_write + 1) % EV1527_DATA_TIME_NUM;
}
}
ev1527_rx_last = 0;
}
enableInterrupts();
}
最新回复 [0]