Analog inputs adc converter

guideon · August 11, 2018, 3:10pm

Hello everybody, we have a project to use soil moisture sensors to trigger realays for smart irrigation.
We have done some test with Arduino stuff and want to move to the BigClown plateform.
However I do not really understand how we can perform analog read as with an ADC converter.
With ADC you can setup 10 or 12 bits, maybe you just need to get the voltage from the sensor module.
So I have the following questions:
Can we use any kind of analog sensors and measure the voltage input.
Where can I find the soil moisture sensor firmware as an example.
Any expected shipping date for the soil moisture kit.
Best regards, Guy.

hub.martin · August 12, 2018, 8:29am

Hello,

soil moisture is using 1-wire digital communication, this blogpost will aswer your questions.
https://www.bigclown.com/blog/2018-07-17-soil-sensor/

Here is the code example

github.com

bigclownlabs/bcf-radio-soil-sensor/blob/master/app/application.c

#include <application.h>

#define SERVICE_INTERVAL_INTERVAL           (60 * 60 * 1000)
#define BATTERY_UPDATE_INTERVAL             (60 * 60 * 1000)
#define TEMPERATURE_PUB_NO_CHANGE_INTEVAL   (15 * 60 * 1000)
#define TEMPERATURE_PUB_VALUE_CHANGE        0.5f
#define TEMPERATURE_UPDATE_SERVICE_INTERVAL (5 * 1000)
#define TEMPERATURE_UPDATE_NORMAL_INTERVAL  (30 * 1000)
#define MOISTURE_PUB_NO_CHANGE_INTEVAL      (60 * 60 * 1000)
#define MOISTURE_PUB_VALUE_CHANGE           5

// LED instance
bc_led_t led;

// Button instance
bc_button_t button;

bc_soil_sensor_t soil_sensor;
struct
{

This file has been truncated. show original

So the communication is digital, we do not use any analog reading over Sensor Module. However you can connect your own sensor to the Sensor Module and read analog values. Let us know if you need some help to connect different sensor.

I asked @hubpav for shipping date, I’ll put that information here when I will know the details.
Martin

guideon · August 13, 2018, 7:42am

Hi Martin thanks for your response.

It is a little bit tricky I had a look to the soil moisture sensor code and I am in trouble.

I have tried to understand the github code but did not found where for example is defined the following expression:
BC_SOIL_SENSOR_EVENT_UPDATE_THERMOMETER

I have checked the SDK and was not able to find a definition.

We target to use two motion sensors with the sensor module one is a surface motion sensor with ambient temperature the other one will be buried under the roots.

The second one is an analog moisture sensor sold by pino tech the arduino voltage values are read with an ADC set to 10 bits. I guess that it is not possible to do so with the sensor module and I do not see how to do it.

The other way should be to use two big clown soil sensors. Could you provide a code example. Best regards Guy