// Lua: read( pin )
static int lgpio_read( lua_State* L )
{
unsigned pin;
pin = luaL_checkinteger( L, 1 );
//MOD_CHECK_ID( gpio, pin );
unsigned level = platform_gpio_read( pin );
lua_pushinteger( L, level );
return 1;
}
/*Lua: result = hx711.read()*/
static int ICACHE_FLASH_ATTR hx711_read(lua_State* L) {
uint32_t i;
int32_t data = 0;
//TODO: double check init has happened first.
//wakeup hx711
platform_gpio_write(clk_pin,0);
//wait for data ready. or time out.
//TODO: set pin inturrupt and come back to it. This may take up to 1/10 sec
// or maybe just make an async version too and have both available.
system_soft_wdt_feed(); //clear WDT... this may take a while.
for (i = 0; i<HX711_MAX_WAIT && platform_gpio_read(data_pin)==1;i++){
asm ("nop");
}
//Handle timeout error
if (i>=HX711_MAX_WAIT) {
return luaL_error( L, "ADC timeout!", ( unsigned )0 );
}
for (i = 0; i<24 ; i++){ //clock in the 24 bits
platform_gpio_write(clk_pin,1);
platform_gpio_write(clk_pin,0);
data = data<<1;
if (platform_gpio_read(data_pin)==1) {
data = i==0 ? -1 : data|1; //signextend the first bit
}
}
//add 25th clock pulse to prevent protocol error (probably not needed
// since we'll go to sleep immediately after and reset on wakeup.)
platform_gpio_write(clk_pin,1);
platform_gpio_write(clk_pin,0);
//sleep
platform_gpio_write(clk_pin,1);
lua_pushinteger( L, data );
return 1;
}
static void transfer(uint8_t* send, uint8_t * recv, uint8_t len)
{
while(platform_gpio_read( PIN_GPIO2 ) == 0);
if(recv == NULL) {
while(len --) {
platform_spi_send_recv(1, *send++);
}
return;
}
while(len --) {
*recv++ = platform_spi_send_recv(1, *send++);
}
}
static void ICACHE_FLASH_ATTR dht22_task(os_event_t *e) {
DHT_DBG("dht22_task");
if(e->sig != SIG_DHT)
return;
//put dht pin on output mode with pullup
platform_gpio_mode(DHT_PIN,PLATFORM_GPIO_OUTPUT,PLATFORM_GPIO_PULLUP);
uint64_t data;
os_memset(&data,0,sizeof(uint64_t));
//init sequence
platform_gpio_write(DHT_PIN,1);
delay_ms(5);
platform_gpio_write(DHT_PIN,0);
delay_ms(1);
platform_gpio_write(DHT_PIN,1);
//enable input reading
platform_gpio_mode(DHT_PIN,PLATFORM_GPIO_INPUT,PLATFORM_GPIO_PULLUP);
//find ACK start
//wait pin to drop
int timeout = 100;
while(platform_gpio_read(DHT_PIN) == 1 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0) {
DHT_DBG("\tACK start timeout");
return;
}
//find ACK end
//wait pin to rise
timeout = 100;
while(platform_gpio_read(DHT_PIN) == 0 && timeout > 0)
{
os_delay_us(10);
timeout-=10;
}
if(timeout==0) {
DHT_DBG("\tACK end timeout");
return;
}
//continue to read data
while(1) {
//wait pin to go low, signaling next bit
timeout = 200;
while(platform_gpio_read(DHT_PIN) == 1 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0) {
//NODE_DBG("\tdata signal timeout");
break;
}
//wait start of bit
timeout = 200;
while(platform_gpio_read(DHT_PIN) == 0 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0) {
//NODE_DBG("\tdata bit start timeout");
break;
}
//mearure pulse lenght
timeout = 200;
while(platform_gpio_read(DHT_PIN) == 1 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0) {
//NODE_DBG("\tdata bit read timeout");
break;
}
int pulseWidth = 200 - timeout;
//shift data
data <<= 1;
if(pulseWidth > 40)
{
//bit is 1
data |=1;
}
else {
//bit is 0
//nothing to do
}
}
//do the math
float temp_p, hum_p;
uint8_t data_part[5];
data_part[4] = ((uint8_t*)&data)[0];
data_part[3] = ((uint8_t*)&data)[1];
data_part[2] = ((uint8_t*)&data)[2];
data_part[1] = ((uint8_t*)&data)[3];
data_part[0] = ((uint8_t*)&data)[4];
int checksum = (data_part[0] + data_part[1] + data_part[2] + data_part[3]) & 0xFF;
if (data_part[4] == checksum) {
// yay! checksum is valid
hum_p = data_part[0] * 256 + data_part[1];
hum_p /= 10;
temp_p = (data_part[2] & 0x7F)* 256 + data_part[3];
temp_p /= 10.0;
if (data_part[2] & 0x80)
temp_p *= -1;
read.temp = temp_p;
read.hum = hum_p;
}
}
int ICACHE_FLASH_ATTR dht22_read(dht_data *read){
DHT_DBG("dht22_read");
//put dht pin on output mode with pullup
platform_gpio_mode(DHT_PIN,PLATFORM_GPIO_OUTPUT,PLATFORM_GPIO_PULLUP);
uint64_t data;
os_memset(&data,0,sizeof(uint64_t));
//init sequence
platform_gpio_write(DHT_PIN,1);
delay_ms(5);
platform_gpio_write(DHT_PIN,0);
delay_ms(1);
platform_gpio_write(DHT_PIN,1);
//enable input reading
platform_gpio_mode(DHT_PIN,PLATFORM_GPIO_INPUT,PLATFORM_GPIO_PULLUP);
//find ACK start
//wait pin to drop
int timeout = 100;
while(platform_gpio_read(DHT_PIN) == 1 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0){
DHT_DBG("\tACK start timeout");
return 0;
}
//find ACK end
//wait pin to rise
timeout = 100;
while(platform_gpio_read(DHT_PIN) == 0 && timeout > 0)
{
os_delay_us(10);
timeout-=10;
}
if(timeout==0){
DHT_DBG("\tACK end timeout");
return 0;
}
//continue to read data
while(1){
//wait pin to go low, signaling next bit
timeout = 200;
while(platform_gpio_read(DHT_PIN) == 1 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0){
//NODE_DBG("\tdata signal timeout");
break;
}
//wait start of bit
timeout = 200;
while(platform_gpio_read(DHT_PIN) == 0 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0){
//NODE_DBG("\tdata bit start timeout");
break;
}
//mearure pulse lenght
timeout = 200;
while(platform_gpio_read(DHT_PIN) == 1 && timeout > 0)
{
os_delay_us(5);
timeout-=5;
}
if(timeout==0){
//NODE_DBG("\tdata bit read timeout");
break;
}
int pulseWidth = 200 - timeout;
//shift data
data <<= 1;
if(pulseWidth > 40)
{
//bit is 1
data |=1;
}
else{
//bit is 0
//nothing to do
}
}
//do the math
float temp_p, hum_p;
uint8_t data_part[5];
data_part[4] = ((uint8_t*)&data)[0];
data_part[3] = ((uint8_t*)&data)[1];
data_part[2] = ((uint8_t*)&data)[2];
data_part[1] = ((uint8_t*)&data)[3];
data_part[0] = ((uint8_t*)&data)[4];
int checksum = (data_part[0] + data_part[1] + data_part[2] + data_part[3]) & 0xFF;
if (data_part[4] == checksum) {
// yay! checksum is valid
hum_p = data_part[0] * 256 + data_part[1];
hum_p /= 10;
temp_p = (data_part[2] & 0x7F)* 256 + data_part[3];
temp_p /= 10.0;
if (data_part[2] & 0x80)
temp_p *= -1;
read->temp = temp_p;
read->hum = hum_p;
#ifdef DHT_DEBUG_ON
char * buff = (char *)os_zalloc(64);
c_sprintf(buff,"%f",read->temp);
DHT_DBG("dht22_init temp : %s C",buff);
os_memset(buff,0,64);
c_sprintf(buff,"%f",read->hum);
DHT_DBG("dht22_init humidity : %s %%",buff);
os_free(buff);
#endif
}
return 1;
}
