Remote control for the fan

It was a hot, really hot, really very hot summer in 2012 in place where I used to live. I bought some cheap fan, though it was quite powerful, but there were two major drawbacks for me:

  1. No remote control
  2. No timer for scheduling switching off, let say at night. And I did not want it to make noise a whole night.
a fan with the remote control
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Pic Lab, PIC16, Experiment #20, The encoder

I needed to get my hands on the encoder, so I started to explore things around it.

First of all, what is the encoder? This is a thing that helps to convert the rotation angle and a direction of rotation to some numbers we can use for our further advance.

Usually, the encoder has three terminals, to connect it I have used the following circuit:

All resistors have a nominal equal to 4.7KOhm.

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Pic Lab, PIC16, Experiment #14, USART (UART) module

Let’s look at USART module in pic microcontroller (uart module).

I’m going to move in two ways:

1. Using existing functions from a hi-tech compiler.

2. Writing my own functions.

USART = UART = SCI – the universal data transmitting/receiving protocol, which can work in synchronous and asynchronous modes. We pay attention to the second mode at the moment, this one is used for communications mostly.

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Pic Lab, PIC16, Experiment #13, Software I2C

I choose the software realization of the I2C protocol as the next experiment. There isn’t a description of this protocol, only realization. The curious soul should google it, there is a lot information on i2c subject.


Goal: To make the connection between PIC16f628a and IO port expander PCA9539 by i2c

What we have: PIC16f628a, PCA9539, devboard.

Why do I need it (in short): I have one project in development state for now. The project is a clock with a thermometer and two seven-segment indicators: the first 4-digit and the second has 3 digits. To control it I need 8+4+8+3 = 23 IO pins, but PIC16f628a has only 16, so in the such configuration, it seems not real to me. In the beginning, I thought about shift register using, but suddenly I received free sample sets from NXP and I took the decision to use PCA9539. In this case, there are only 9 pins to be used, and two pins from it are for I2C communication between pic micro, RTC clock, and the thermometer.

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Pic Lab, PIC16, Experiment #12, EEPROM

Goal: To write and read EEPROM

What we have: PIC16f628a and a simple devboard.

Microcontroller PIC16f628a has 128 bytes of EEPROM memory on board, not too much but we have what we have. Hi-tech PICC compiler has internal functions for work with EEPROM, but here I’m going to make some my personal functions.

Let’s look at the EECON1 register:

from the mikroe resourse
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