I found it is hard to make RF transceivers even with years of expereince. Even it is a kind of worthless when the working guaranteed modules are already available. nRF24L01.jpg NRF24L01 Wireless Transceiver Module is one good example. You can buy two of them for < $8 and I'm sure it will cost you mo...

We have worked with DS1307 RTC which works over I²C. I guess DS1387 is also the same.
Have a look at How to interface Real Time Clock DS1307 to PIC16F84.

DS1307 is one of the devices that used widely in micrcontroller applications. It provide Serial Real Time Clock is a low–power, full BCD clock/calendar plus 56 bytes of nonvolatile SRAM. Address and data are transferred serially via the 2–wire bi–directional bus.The clock/calendar provides seconds, ...

You are correct. It is always good to find the cheapest micro that satisfy the minimum requirements. However when you are learning, it is very good to work with a micro with good help. PIC 16F877A is one of them and I remember I told you this before. Have you considered the oscillator in PIC12F629? ...

This page shows an example on how to drive a unipolar stepper motor. These motors can be found in old floppy drives and are easy to control. The one we use has 6 connectors of which one is power (VCC) and the other four are used to drive the motor sending synchronous signals. ULN2003A driver chip ha...

In this tutorial, we will cover the basics of Arduino’s SPI (Serial Peripheral Interface) capabilities, as well as the AT25HP512 chip, which is a serial EEPROM, used to store data. This chip runs at 10MHz at 5V and is organized into 512 pages of 128 bytes each, giving us 65,536 bytes of data storage...

This is the simplest Arduino demo, used to verify that everything is working - and will result in a blinking LED connected to a DIGITAL IN/OUT pin on the Arduino. When a DIGITAL OUT pin on the Arduino is set HIGH, 5VDC will be sent out on the pin. 5VDC is too much voltage for a typical LED to handle...

Each digital pin on the Arduino has an internal pull up resistor that can be turned on and off using the digitalWrite() command when it is configured as an output. When it is HIGH, 5V sent to the pin and can deliver 40mA of current. This is adequate to power an LED, but most devices that you will wa...

You may want to use the Arduino to control a DC powered device that draws more current that the 2N3904 transistor can supply. A solution for this situation is to use an NPN Darlington Transistor designed for medium power linear switching applications. In this tutorial we will use a TIP122 transistor...

Just posted something relevant for you Is it a coincidence?

You should use a LED driver to connect a 7-segment LED array to a microcontroller. Have a look at How to use MAX7221 to drive 7-segment LED set using a micro.

Good luck!