The sensor sounds like work if this condition at dht.c line 42:

if (elapsed_cycles >= max_wait_cycles)

if (elapsed_cycles > max_wait_cycles)

Could be an error in the Zephyr's DHT driver?

Att, T. Primini

On Tue, Feb 6, 2018 at 8:32 AM, Tiago Primini <primini@...> wrote:

Hi everyone!

 

We are working on a PoC using SDK Nordic nRF52 + Aosong AM2302 sensor + Zephyr. The AM2302 sensor works like DHT22 that is already implemented in Zephyr, but due to some reason, our implementation is not working properly.

Basically, we follow the sample available in hts221 folder, but using DHT22 driver. The function sensor_sample_fetch is returning an error. We saw in dht.c that the condition (dht_measure_signal_duration(drv_data, 1) == -1) is being the cause of the read error.

 

Our prj.conf file is configured as:

CONFIG_GPIO=y
CONFIG_SENSOR=y
CONFIG_DHT=y
CONFIG_DHT_CHIP_DHT22=y
CONFIG_DHT_GPIO_PIN_NUM=3

Have you already use DHT driver in Zephyr?

 

BR,

 

Tiago Primini