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Wednesday, October 31, 2018

Arduino adjusting clock with dual thermometers


   Inspired by Arduino Digital Clock & Thermometer article, I change the schematic for use 2 sensors DS18B20 instead DHT22 (DHT11) sensor:
   Bogdan Arnautu, a blog reader, test the clock:
    With uploaded clock_2ds18b20.ino sketch, Bogdan made clock with 2 thermometers video:

Saturday, October 27, 2018

matrix mini clock with alarm, thermometer and hygrometer (3)

original article
    After few nights and days than test the clock, I change style for usualt temperature... without sign and normal C...
    Also, I change for positive and negative values 
- small than 10 degree Celsius
- bigger than -10 degree Celsius
- lower than -10 degree Celsius
   You can see in matrix mini clock with alarm, thermometer and hygrometer (3a) video nea display modes:

matrix mini clock with alarm, thermometer and hygrometer (2)

original article
   Because I use DHT22 (AM2302 sensor) am change the sketck (mini_clock_1_3_b.ino)  to see temperature with number after decimal point, like in next photo
- negative tmperature > -10 degree Celsius:
- negative temperature more than -10 degree Celsius
- positive temperature less than 10 degree Celsius
- positive temperature more than 10 degree Celsius

matrix mini clock with alarm, thermometer and hygrometer

   After some time, I update project "mini clock" with DHT sensor, schematic is now
  
  Because, I realize in original program I haven't all characters I need, I "reverse engineer"-ing  file with characters using Hexadecimal to Binary Converter to made new charactes:
So, character are vertical and from up to down. so I design my characters:
     Now, my character file has new characters 😆
   For not be problems, I remane my file as and put near original file
So, for testing, I simulate al cases:
- low humitity (< 10%)
- normal humidity 
- 2-digit negative temperature:
- 1-digit negative temperature:
- 1-digit positive temperature:
- 2-digit positive temperature:

    I use DHT22 (AM2302) sensor so sketch is
and if you have DHT11 just change to
   I use RTC with DS3231, but work without changes with DS1307 (note; DS3231 is more accurate than DS1307)....

Saturday, October 20, 2018

6 Digit 7 Segment HT1621 LCD Display Module with Arduino

   I buy from Gearbest an interesting lcd display with 6 digit 7-segment drived by HT1621 chip.
  I search informations about this display and Arduino development board and I find few articles, but more usefull was article from http://www.14core.com/wiring-the-6-digit-7-segment-2-4-inch-ht1621-lcd-display-module-on-microcontroller/. I test the schematic presented in article
with HT1621_test.ino sketch and on display is 23:45 clock with animated second and after 17 degree Celsius:
This mode can be see it on HT1621 6 digit 7 segment LCD display test video
   After some search and study I can put easy decimal point, so, using HT1621_test4.ino sketch, on display is a random hour clock with animated seconds indicator (between hour and minutes)
and random temperature (negative and positive)
   In HT1621 6 digit 7 segment LCD display - test 2 video you can see this display mode: