Input devices

In this week I studied different types of sensors under input devices assignment.In this week I decided that to make a level sensor.In previous assignment that is in output devices I was mentioning about desolved oxygen sensor,but that sensors are expensive and that are'nt available on locally.Then I was changing my plan to use LDR sensor for this assignment.I was trying that sensor and studying too.

The purpose was simple! I need to run motor at night by using solar panel batteries.That's why I chose LDR sensor. I just make trial on that sensor by using bread board.After that Dr. Yogesh Kulkarni who is mentor of this project, suggest me that you should work on a level sensor. Then I realize actual problem and solution of my project.

In this system by using level sensors input, I will operate solenoid and motor too.

Then I am working on to design a circuit,which will gives variable voltage when water level increase or vice versa condition inside the tank.

I was taking only smd pad for milling. There is no any resister will solder here. I want to solder probe wires so, in eagle file I was taking resister over there.

I milled this board two times.Because of bed level modella machines. It looks like this..

After fixing that problem , I will design water level indicator.Which will sense the water level and after that gives signal for the motor and solenoid through relay circuit.Firstly, I program level sensor and taking resistance variation.

I was soldering the sensor parts and connecting wire for the water reading.

After doing soldering of board I moved towards the programing of my board using hello board. I was using ardiuno board for programming the hello board.

You should declare sensor pin in the program. When I was trying programming with Attiny 44 , it gave error like serial was not declared. Then I read data sheet of the attiny44 then I realize that there is no in built pins inside the microcontroller. You have to mention inside the code that which pin is your Rx pin Or Tx pin.

But similar problem happens. Serial was not declared error occure during uploading the program.

So, I was using ardiuno IDE for programming. When I put probe inside the water it reads/prints serially value below 600 and when put out from the water it gives value above 600 . Then I design new board with attiny 45. I was reading data sheet of attiny 45 during programming the micro controller.

watch input measurement

I was designing microcontroller board for the input devices by using attiny45 as IC.

I was using autodesk eagle software for the electronic design. Then by using modella machine I was milling PCB board. I use 1/64 milling bit for the milling the PCB and 1/32 bit for the cutting the PCB.

I milled and solder the board but it founds attiny 45 doesn't working condition. So, I design another board for the same operation.

In this programming I was declared PB0 pin as my indicator pin and PB1 pin for CRO reading. In this programming I was declaring PB5 as my sensor pin. You can watch video by clicking below link.

Measuring input by using CRO

CRO used for measuring the voltage, time period, frequency, peak voltage, peak to peak voltage and RMS voltage, we use Waveform Viewer, for measurement in EDWin. For programming this board I was using Attiny 45 data sheet. I got information about the all pins wich recieves input and output signal. So, we can declare any pin for the input and output. In my case I took PB5 as my input pin and PB0 as output pin which is connected to CRO for measuring the output.

I was using output devices microcontroller. Actually I was making that circuit for both the input and output devices. But as per evaluator suggetions I made seperate controller for the input devices. Connections for this controller as same as previous controller. In this controller circuit I just remove relay switch. In this circuit I was using Attiny 45 microcontroller. The code and eagle files of input microcontroller circuit zipped in the download folder.

I was taking reading for confirmation of sensor is in working condition or not. So, you can watch this by clicking on this link!

modified microcontroller measurement

So, in this assignment I have learned how to program attiny 45 and coding too.I learned how to operate CRO for measuring input signals. My lab instructor (Mr.Suhas Labade) helps me lots in coding .

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