EC6711 EMBEDDED LAB Manual – ECE 7th SEM Anna University

ADC INTERFACING WITH ARM PROCESSOR

APPARATUS REQUIED

1. ARM processor, EK-TM4C123GXL 2. Computer with energia software.
3. 1kΩ Resistor – 5 nos
4. Bread Board.
5. Connecting wires

THEORY

Five 1kΩ resistors are connected in series. 5V is supplied and the circuit is closed by the ground. 5V is applied across 5 1kΩ resistors, so each resistor drops 1v, totally 5v. Test point in ground, it produces 0 analog voltage, From ground after the first resistor produces 1 analog volt, after the second resistor produces 2 analog volt, after the third resistor produces 3 analog volt, after the fourth resistor produces 4 analog volt, all these test point voltage nodes are connected with the analog IN pin of ARM processor one by one. Program is written to read analog value in analog pin using analog read syntax and this received scale value in program is converted by multiplication factor and can be displayed as 1,2,3,4 volt as digital numbers. Finally analog voltage across the resistors is displayed as digital voltage value numbers in ARM processor serial monitor.

PROCEDURE

1. Connections are given as per the circuit diagram.
2. ADC energia program is loaded in ARM processor.
3. Open the serial monitor in energia
4. In circuit connect analog pin to test point – gnd, 1, 2, 3, 4.
5. Observe the respective digital voltage values in serial monitor as 0,1,2,3,4