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One 4-digit 7-segment LED display like this.
Or four single digit numeric display like this one.
Temperature and humidity sensor DHT22.
https://github.com/DmitryDzz/ArduinoLibraries/tree/master/libraries/DHTlib
This library is http://playground.arduino.cc/Main/DHTLib fork. HumidityInt10 and temperatureInt10 fields where added.
https://github.com/ringerc/Arduino-DHT22
Temperature output samples: [ 0.1°], [-0.1°], [ 1.2°], [-1.2°], [12.3°], [-12°], [123°]. For temperatures less than -99° and greater than 999° the output will be [Err°].
Humidity output samples: [ 9.9H], [47.8H], [99.9H], [100H].
Error code samples: [Err5], [Err°].
- Err1: Checksum error
- Err2: Time out error
- Err3: Connect error
- Err4: Ack Low error
- Err5: Ack High error
- Err°: Too long temperature string
- DHT22 sensor: A7 for Arduino Pro Mini Atmega328 (A4 for Arduino Uno)
- Mercury switch*: A6 for Arduino Pro Mini Atmega328 (A5 for Arduino Uno)
- Digit 1 pin (PWM): 11
- Digit 2 pin (PWM): A0
- Digit 3 pin (PWM): A1
- Digit 4 pin (PWM): 3
- Segment A pin: 12
- Segment B pin: A2
- Segment C pin: 5
- Segment D pin: 7
- Segment E pin: 8
- Segment F pin: 13
- Segment G pin: 4
- Segment DecimalPoint pin: 6
(*) Mercury switch is connected to the input pin (INPUT_PULLUP mode) and one of GND pins. In case the switch is connected the display is off by default. It is turned on after shaking the switch for a second. And it is off again after LED_TURNED_ON_DURATION milliseconds.
- AUTO_START - should be false if mercury switch is connected
- LED_TURNED_ON_DURATION - time in milliseconds the LED display is turned on after shaking
- MODE_DURATION_IN_MILLIS - temperature / humidity pause time
- READ_DELAY_IN_MILLIS - sensor read interval
- COMMON_ANODE_LED - set true for LED with common anode, false for LED with common cathode
- BRIGHTNESS - 0 is min value, 255 - max
- DIGIT_DELAY_IN_MICROSECONDS - delay to light up one digit