Blog Archives
Posted on 11 May 2008
Kees Krijnen writes:The Microchip PIC16C84 was one of the first serial in-system programmable microcontroller. I saw PIC serial programmers published in Electronic magazines in 1993. Today, many PIC programmer circuits - for serial and parallel PC ports - are published on the Internet.Despite its somewhat unusual design - like the 128 byte page RAM/Register direct/indirect memory mapping - it is a popular microcontroller, easily available and programmable now as flash microcontroller 16F84. The developer environment MPLAB from Microchip is free of charge and many application examples are available.[more]
Posted on 09 Apr 2008
The PICADC is a simple 12-bit, 8-channel analog to digital converter (with 4 additional digital inputs), which may be connected to the PC through the serial interface (RS232).
The sequence of sampled channels, and sampling frequence are programmed by the PC.
The maximal sampling frequency is limited by the data transmission rate, and at 115200 baud is equal to ca. 3kHz for 1 channel without digital inputs, and to ca. 500 Hz for 8 channel with digital inputs.The analog input voltage range is -2.5V to 2.5V.The digital inputs may be used for recording additional digital signals, eg. the time code used to synchronize the recorded data with other events.The PICADC is based on PIC16F84 (or PIC16C84) microcontroller, and MAX190 (or MAX191) ADC.[more]
Posted on 17 Mar 2008
This is PIC16F628 and pic16f84 base inductance/capacitance meter design by Phil Rice VK3BHR.Measuring range is from 0 to >0.1uF for capacitance and 0 to >10mH for inductance.Expected accuracy is +/- 1% of reading +/- 0.1pF or +/- 10nH.This project is a combination of two stolen designs.The oscillator design originally came from the AADE LC meter web page. It uses an LM311 comparator with positive feedback to make a parallel LC oscillator with digital output. It seems to oscillate readily over a wide range of L and C values. Hopefully, it follows the “well known formula for resonant frequency”.The frequency measuring part is a cut down version of the September 2002 Frequency Meter article from Amateur Radio magazine. The original idea for this came from the web pages of Eamon Skelton, EI9GQ.[more]
Posted on 08 Mar 2008
Parallel interfacing LCD with MCU at least need 6 I/O pins (4 bit mode) and maximun can up to 11 I/O pins (8 bit mode). The I/O pin can be cut down to 3 pin by serial iterfacing using shift register. They were few shift register can be used such as 74HC164, 74HC595, CD4094 and any compatible 8 bit shift register. Before you attempt to do serial interfacing, it is good pratice to familiar with parallel interfacing. You can find many reference from internet.Following diagram show the serial interfacing Hitachi compatible 2 X 16 LCD modules with Pic16F84 or Pic16F628 MCU.[more]
Posted on 13 Feb 2008
This is one of the most neat projects to build using a PIC. The design of the clock is mainly a clone of Bob Blick’s propeller clock, along with a few modifications of mine. I used a PIC16F84A, basically an improved version of the 16F84 and the 16C84.[more]
