ADC Functioning of AtMega16

[CK]

Hello, 

I have given 4 sensor inputs to the ADC port (Moisture Sensor, Battery Level Indicator, Rain Sensor and Water Level Indicator).

However, i do not get the desired output, maybe due to the load on micro controller.

The voltage level drops when displayed as output.

How to get the actual voltage output?

Is there a way to reduce this load on micro controller?

 

ADC functions:

double Read()

{

ADCSRA|=(1<<ADSC);

while (ADCSRA & (1 << ADSC));

ADCSRA|=(1<<ADSC);

while (ADCSRA & (1 << ADSC)); 

_delay_ms(200);

return ADC;

}

///////////////////////////////////////////////

void InitADC(unsigned char ch)

{

   

 

ADCSRA=(1<<ADEN)|(1<<ADPS2)|(1<<ADPS1);

ADMUX = (ADMUX & 0xF8)  | ch;

_delay_ms(200);

return;

}

 

 

[AJISH ALFRED]

 

There are 8 adc channels for atmega16. If you connect your sensors to any 4 seperate channels, there won’t be any issues of loading. You can then switch the channels before take reading of each.

By the way, you have’nt said anything about your expected output.

[CK]

hello,

The  microcontroller’s pin number 40 is connected to moisture sensor, pin number 39 is connected to battery indicator, pin number 38 is connectd to water level indicator , pin number 37 is connected to rain sensor.

i am using 12V battery

Excepted output : 5 , 12 , 5 , 5

output getting :0.073 ,5.000 , 0.092 , 4.0804

[AJISH ALFRED]

 

Have you connected adc reference voltage pin, pin32 ADREF to 5V ?

[Author]

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