Experiments with PIC16F628A

HD44780 based character LCD displays are very popular among hobbyists. They are easy to interface with microcontrollers and most of the present day high-level compilers have in-built routines for them. However, the bad part is at least 6 I/O pins of microcontroller are required to use them in your project. Therefore, they are not applicable for 8-pin devices like PIC12F series microchips. The aim of this project is to allow LCD interfacing to such devices using 3-wires. I am going to demonstrate this with PIC12F683 microcontroller. The character data or command from the microcontroller will be transferred serially to an 8-bit serial-in parallel-out shift register (74HC595), and the parallel output will be fed to the LCD driver pins.

If you have an old Nokia 3310 cell phone, don't throw it away. You can use its LCD screen for this cool project. This project describes the use of such a LCD to display temperature.  It uses PIC12F629 microchip as a brain that reads temperature measurement from a DS18B20 sensor, and displays it on a Nokia 3310 LCD screen. Source:  http://www.ivica-novakovic.from.hr/Nokia%20Lcd%20Termometar-eng.htm

For past few days, I have been working on a PIC12F683 based temperature data logger. I just finished this project and the product is available on my PIC12F683 blog page.This is how the finished product looks like. It reads temperature values from a DS1820 sensor and stores in its internal EEPROM. It has 3 selectable sampling intervals (1 sec, 1 min, and 10 min). Three tact switches provides 7 functions, and this runs with 3  AAA batteries. It can be interfaced to a PC through serial port, and also has an ISCP header for firmware upgrade.

With mikroC built-in library, use of ADC on PIC microcontrollers has become more simple. PIC16F628A doesn't have in-built ADC in it, so I am going to demonstrate this with my PIC12F683 development board. The analog input will be given through a potentiometer, and the 10-bit digital output will be displayed on a hyperterminal window on PC.

I have recently made a new PIC development board for PIC12F683. It is an 8-pin microcontroller with a lot of good features including 10-bit ADC and PWM. The development board has following features: 1. A Regulated +5V power supply. 2. 3 Red LED outputs which can be connected to any GPIO pins using jumper wires. 3. An ON/OFF power supply switch. 4. A Green LED as a power ON indicator. 5. An 8-pin IC socket for PIC12F683 microcontroller. 6. Two potentiometers: one for providing Vref, and other for simulating analog input to ADC. 7. An ICSP header connector. 8. Two tactile switches for input operation. 9. A TTL to RS232 level shifter using a transistor circuit. 10. A piezo buzzer. 11. A DC motor with driving circuit. 12. Access to individual pins of PIC12F683 through female header pins.