Soil moisture (humidity) control system

   Helpfull for home is a soil moisture control system, who can made easy with a Arduino development board.

   For tests I use a Arduino Mega board, alpahanumerical 1602 LCD with i2c interface, soil moisture module, but for real use must use relay module for control a wattering pump.

   I use sketch named lcd1602_i2c_soilhumidity_ver1.ino who can find at my Github channel.

   Soil moisture sensor is very chip

and has this schematic:

   My soil moisture sensor is not permanent powered with 5V because in timp probe sensor will be distroyed by electrocorrosion effects, so, I powered the sensor just few seconds at 5 seconds when pump is on for avoid flooding and at 5 minutes (in test I use 20 seconds) when soil is wet.

   I made a few years ago some tests with CMOS 4093 gates (see original article from  http://www.arduinotehniq.com/old/udare_automata/udare_automata_flori.htm) when I use this schematic whit permanent power of soil probe:

and after 3 months my stainess steel probe was corroded:

   So, I put a threshold value at 25% and I have 2 cases:

- when soil is wet, pump is off, measurements are made at long periods:

- when soil is dry, pump is on, measurement are made at 5 seconds for avoid floods:

   You can see these cases in a movie named soil moisture control system using Arduino

Soil moisture (humidity) measure system

   A nice and interesting gadget for Arduino board is soil moisture sensor, who can buy from Sparkfun,

ebay, aliexpress, banggood, etc.

   For last version schematic is:

   This version has 2 outputs, one analogical and one digial. If value of humidity is bigger than reference led D2 is on:

   I use a LCD1602 with i2c interface with a Arduino Mega (ADK) board and my test schematic is:

   I write a sketch named lcd1602_i2c_soilhumidity_ver0.ino put on my github channel:

   If sensor has probe in the air:

and if I put wet fingers:

  I made a small movie named soil humidity measure system on alphanumerical lcd display

and than I put a clone Arduino Uno board:

and made new movie, named soil humidity measure system on alphanumerical lcd display (2)

   Next step was to I use a Arduino Leonardo:

and a movie named soil humidity measure system on alphanumerical lcd display (3)

Arduino on VGA display

original article in Roumanian language

   I search for info about how can use Arduino as VGA tester or video card.
   First credible article is Simple VGA/Video adapter who can use 8-bit AVR MCU like ATmega8, 328, etc:

   Article is writted by Maxx Ibragmov and a their montage is:

   On TV, resolution is 20 rows with 38 character each:

and on VGA monotor, resolution is 20 rows with 20 characters each:

  I wanted fast result and try other adapter montage (without diodes):

   First test was with info from article Arduino generated VGA (color) signal - Complete!

who use this schematic:

   I use Arduino IDE 1.0.3 and my test image is:

NOTE (27.09.2017): Now site is "down", so you can download usefull files from https://github.com/LaboratorioDeGaragem/VGA-com-Arduino !

   I try to reproduce a more complex image like in article Arduino generated VGA (color) signal - Complete! (other site, same author):

but image is not clean.. and I jump to other material find in article Basic Arduino VGA:

   I use same Arduino IDE 1.0.3, but my test image is not same in original article:

   Next step was to reproduce expermiments from Nick Gammon with VGA

   First is a black/white VGA video card for 30 rows with 20 alphanumerical characters each. Schematic is simple:

   This VGA video card use i2c protocol for comunicate with other Arduino board, but results are very poor on transmision data (author say: unfortunately incoming data (can) make  the display "glitch"). I made a movie (explanations are in Romanian language, but you may can understund what I want to say):

   Next test was with moving colour test image on VGA display, using this schematic:

and a image is:

   I made a movie with image on VGA (saame, with explanations are in Romanian language):

   Next step was to test VGAX library writted by Sandro Maffioda after Nick Gammon info.. on display resolution is 120x60px with 4 colours.

   Schematic is simple:

   You can made some combination:

1) red & green made: black, red, green & yellow:

2) red & blue made: black, red, blue, purple:

3) green & blue made: black, green, blue, cyan:

4) red & cyan (green + blue) made: black, red, cyan, white:

5) blue & yellow (red + green) made: black, yellow, blue, white:

6) green & purple (red + blue) made: black, green, purple, white:

   I made some movies for understund more easy: