1btn: Open Source Wi-Fi connected IoT Button

What is 1btn?1btn-2-1_jpg_project-body

1btn (one button) uses the internet to complete a task with the simple, satisfying click of a single button. It connects to the internet over Wi-Fi to trigger whatever action you have assigned to it using a simple, online interface. One click, one task. It’s that simple.

You can support this project:  https://www.crowdsupply.com/knewron/1btn.

1btn: Open Source Wi-Fi connected IoT Button

Solar-powered AM2315 Sensor

After recharging the LiPo akku over the last night I started the test again. I increased the sleep time to 10 minutes to get better compare to a test before. This test was documented at https://drive.google.com/drive/folders/0BwUOc1bstFZ9Zm1JbUlORDNua2s. Under these conditions I got a runtime of 48 days from February to April.

You can follow the measuring results at http://www.ckuehnel.ch/AM2315@NODEMCU.html again.

I added a weather widget from kachelmannwetter.com to see the correlation between weather situation (means sun) and the voltage of the LiPo akku.

Solar-powered AM2315 Sensor

Solar-powered AM2315 Sensor

The test run started on 2016-04-13 stopped today. This was a run time of 15 days. We had horrible weather conditions. Temperature around 0° C at night, rain and a few sun over the day only.

At 5:25 the battery voltage was 2.4 V only. At 8:11 the node restarted after re-charging, but stopped at 8:37 again. This short periode of re-charging was not enough. Now, we are waiting for the sun…


Solar-powered AM2315 Sensor

ESP8266 Grove Kit arrived


Easy connection of Grove Sensors/Actors to NodeMCU/ESP8266.

You can buy this board via Aliexpress for $ 10.




But, pay attention, the connectors here differ in size from original Grove connectors. To document this I placed an Arch Pro board with two Grove connectors and the ESP8266 Grove Kit on the table and took an image. The difference is obvious.

Grove Connectors

The data sheets from original Grove connectors are here (Grove Connector 1)(Grove Connector 2). The distance pin-to-pin is 2 mm there.


ESP8266 Grove Kit arrived


AM2315The AM2315 is a temperature & humidity sensor with an I2C-interface in a nice enclosed style. The sensor contains a DS18B20 temperature sensor and a capacitive humidity sensor. A microcontroller inside builds the sensor interface and works as an I2C-slave.

For outside measurements it is also advantageous that the AM2315 comes in a rugged case with mounting bracket. While it is not rated as ‘weatherproof’, it is more suitable than SHT PCB-breakout sensors for measuring outside.

After crimping a Grove-connector we can connect this sensor to a Grove Arduino sheld hooked on a Wemos D1 board, for example. Or you connect the wires to a Wemos D1 mini.


At Github you will find an AM2315 Lua module and it is easy to integrate the AM2315 into your own application. I have included the AM2315 sensor into my DHT11 network and it sends now outside data to the MQTT. Its ID is ESP8266-13972685.

The data coming from the AM2315 sensor are marked red in the screenshot while the data of another outside sensor ASH2200 are marked orange. The two sensors are outside but at different locations.


The software am2315.lua and am2316_mqtt.lua is on Sourceforge and Github.


NodeMCU for the ESP32?

Espressif dveloped the ESP32 and NodeMCU users wait for this more performance offering CPU. The information is rare, yet.

In the NodeMCU repository on Github I found some discussion about the state of development and this nice diagram revealing some internals and peripherals.


It would be nice to hold this device programmed with NodeMCU firmware in hands asap. If you have further information please add it to get a better picture of what we can expect.

I received an interesting link from DIY India Magazine with some more information.

NodeMCU for the ESP32?