Question

An Arduino Uno is configured with the voltage divider connected to Analog input pin A0 as shown, and the code shown below is uploaded. What happens? testCodeA | Arduino 1.8.1 1 Hourly Build 2019/10/29 11:12 As dum o testCodeA Uno #define LED 13 5v void setup) { pinModeCLED, OUTPUT) ; } 13 5k-R Ap void loop) int voltage-anal ogRead (A0) ; if (voltage 1024/2) digitalWrite(LED, HIGH); else R digital Write(LED, LOW); } GND Done compiling. Sketch uses 778 bytes (2%) of program storage space. Maximum is 32 Global variables use 9 bytes (Ø%) of dynamic memory, leaving 2039 14 Arduino/Genuino Uno on /dev/cu.usbmode m 14 10 1

Answer 1

The LED stays on always.

The voltage at analog pin A0 = 0.66*5 V ( By voltage division).

In the output of analogRead 1024 is equivalent to 5 V.

So as 0.66*5 > 0.5*5 , first if statement is true and hence the led will be given high voltage and thus it will stay on.