Electronics-Lab.com Blog

DS1820 based digital thermometer with pic16f84

DS1820 based digital thermometer with pic16f84 - [Link]

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. [via]

PIC16F84 Serial Programmer - [Link]

The clock is synchronised via the German time signal DCF77. It has a display with automatic brightness control and a RS232 computer interface. Arvin writes:

The clock is built around a PIC16F84 microcontroller from Microchip. I chose this microcontroller since its FLASH memory is easy to program and assembler and programmer software is freely available for GNU/Linux. It has 13 general input/output pins which is just enough to implement all the feature I wanted.

[via]

A DCF77 Clock with RS232 Interface - [Link]

To control a webcam with two servo motors (pan and tilt). Easy and simple to build, only need some basic knowledge about electronics and programming. This circuit is based on a PIC16F84 Controller. The total cost of the project is about 40 Euro (40$) including two servo motors and one PIC16F84. All the software/code can be downloaded as free or shareware. [via]

Building a robotic webcam - [Link]

The purpose of this project is to present a device that is useful and at the same time demonstrate to the beginner many features involved in programming the PIC. Some of the topics included are:

* Simple use of MPASM assembler
* Demonstration of use of timer 0 and the prescaler
* Use of length of instructions to set up timing delays
* Using interrupt routines
* Detection of switch closures including debouncing
* Saving and recovering data from the onboard EEPROM

[via]

Darkroom Timer - [Link]

This is the Frequency Counter for 100Hz-2.5GHz, using LCD 16 chara.x 2 lines ,TCXO 12.8MHz(1ppm ) and PIC16F84. The Voltage (0-510mV) of the input signal is also indicated on the LCD , therefore tuning of the coil can be conducted while checking the frequency. Furnished with IF offset-function, this can be applied for the frequncr display of the home brewed transeiver. Print circuit board size is very small of 100mm x 43mm. [via]

Frequency Counter – [Link]

Rob Arnold writes:RF is just way too cool not to use in your designs. But if you’re a newbie like me it is difficult to successfully build solid RF transmitters and receivers. When I started out I didn’t realize that the larger breadboard I was working off of was causing a lot of the signal deviance because the metal traces on the breadboard worked like small capacitors and changed my circuit dynamics. So after much research I found the Reynolds Electronics RWS and TWS 434 RX/TX pair. I looked into a similar product by MING Microsystems and Radioshack but the Reynolds were superior in performance, cost and ease of use. So with that and two PIC16F84’s I started working on my serial RF link from my control interface (Joystick) to my robot. [via]

RF Modem Robotics Project - [Link]

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. [via]

Serial interfacing LCD with Pic Microcontroller - [Link]

The purpose of this timer is to provide a countdown time from 1 second to 99 minutes & 59 seconds. I use it to control the lighting for the Ultra-Violet exposure of photosensitive PCB material. The project provides also an audible alarm at the end of the countdown time and switches the UV lights by means of a relay. It is based on a Microchip microcontroller, the 18 pin PIC16F84(A). This microcontroller contains 1Kbyte of flash memory for program code, 64bytes of static RAM memory, and 64bytes of EEPROM memory which are used here to store up to 15 different (user-programmable) countdown times. [via]

PIC16F84 Countdown timer for PCB exposure unit - [Link]

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. [via]

Surprisingly Accurate Digital LC Meter - [Link]