int dht11_read(int gpio, int* temp, int* rh) {
unsigned int cs, expected_cs;
int max_cycles = 100000, thresh;
/* Get DHT11's attention. */
set_gpio(gpio, 0);
os_delay_us(20 * 1000);
/* Switch GPIO pin to input and let it stabilize. */
read_gpio_pin(gpio);
os_delay_us(1);
/* Starting with high, wait for first 80us of L. */
await_change(gpio, &max_cycles);
thresh = await_change(gpio, &max_cycles); /* First 80 us low. */
/* Then 80us of H. */
thresh += await_change(gpio, &max_cycles); /* Then 80 us high. */
if (max_cycles <= 0) return 0;
/* We use this to calibrate our delay: take average of the two
* and further divide by half to get number of cycles that represent 40us. */
thresh /= 4;
/* Now read the data. */
cs = (*rh = dht11_read_bits(gpio, 8, thresh, &max_cycles));
cs += dht11_read_bits(gpio, 8, thresh, &max_cycles); /* Always 0. */
cs += (*temp = dht11_read_bits(gpio, 8, thresh, &max_cycles));
cs += dht11_read_bits(gpio, 8, thresh, &max_cycles); /* Always 0. */
expected_cs = dht11_read_bits(gpio, 8, thresh, &max_cycles);
/* printf("%d %d %d==%d %d %d\r\n", *temp, *rh, cs, expected_cs, thresh,
* max_cycles); */
return (max_cycles > 0 && cs == expected_cs);
}
ICACHE_FLASH_ATTR static v7_val_t GPIO_in(struct v7 *v7, v7_val_t this_obj,
v7_val_t args) {
v7_val_t pinv = v7_array_get(v7, args, 0);
int pin;
if (!v7_is_double(pinv)) {
printf("non-numeric pin\n");
return v7_create_undefined();
}
pin = v7_to_double(pinv);
return v7_create_boolean(read_gpio_pin(pin));
}
int oem_gpio_set_irq_type(int gpio, unsigned int type)
{
if(type == IRQ_TYPE_EDGE_BOTH){
if(read_gpio_pin(gpio)){
type = IRQ_TYPE_EDGE_FALLING;
}else{
type = IRQ_TYPE_EDGE_RISING;
}
}
if(type == IRQ_TYPE_LEVEL_MASK){
if(read_gpio_pin(gpio)){
type = IRQ_TYPE_LEVEL_LOW;
}else{
type = IRQ_TYPE_LEVEL_HIGH;
}
}
switch(type){
case IRQ_TYPE_EDGE_RISING:
__gpio_as_irq_rise_edge(gpio);
break;
case IRQ_TYPE_EDGE_FALLING:
__gpio_as_irq_fall_edge(gpio);
break;
case IRQ_TYPE_LEVEL_HIGH:
__gpio_as_irq_high_level(gpio);
break;
case IRQ_TYPE_LEVEL_LOW:
__gpio_as_irq_low_level(gpio);
break;
default:
return -EINVAL;
}
return 0;
}
