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Links for programming Microchip PICs:

Software: The Flash PIC programmer - recommended.

Hardware: I've built and used the Trivial Low Voltage Programmer with FPP to drive it and
the combination worked fine. There is a Trivial High Voltage Programmer design around,
for those older chips which do not support Low Voltage Programming.

I've built my version using a CMOS non inverting buffer, and a couple of zener diodes
and a red LED in series for the main supply of 5 V and the programming supply of around 13 V.

The simpler versions of PIC programmers do not include means of reading the device.
You are then operating blind, because the success or otherwise of the programming operation
has to be guessed at.

Was the defect in the program? Or did the device fail to program? With a programmer
capable of verifying (by reading back) you can eliminate one element of doubt, which is
a great help when you are trying out a program of your own.

After trying both, I've come to the conclusion that Low Voltage Programming does not offer
any advantages to the hobbyist and that High Voltage Programming is better.
It frees up a port pin and you have to use a wall wart to supply the programmer anyway. So
here are my designs for a programmer using the CD4050 CMOS non-inverting buffer. Since
this is a slow chip, glitches at the input do not get passed through to the PIC. Hence my version
might be expected not to misbehave with long cables to the computer port. This is based on
very limited experimental observation, however.


All of us screw up, one time or the other. Relax. Other guys do it, too.

Circuits

A headphone amplifier using a bipolar operational amplifier.

My Universal PIC Programmer . You drive it with the Flash PIC programmer.

Another approach to an Atmel 89C2051 programmer capable of reading back also,
using just one general purpose integrated circuit.

A serial terminal built with a PIC16F628A and HD44780 single line LCD module
for connecting to the serial port of a computer. This could be used, for example,
on a dedicated computer used as a file or print server instead of a large monitor.

Propellor clock - my attempt to display time using seven whirling LEDs on a stick.

Capacitance and ESR meter circuit, pcb patterns and source code. The parts are
an 18f876, an LM339 and a few transistors.

Speaking Clock circuit and pcb for the blind. Tells time when you clap. Source code.

LCD Clock circuit with program space left over for expansion. Source code four bit
interface for 16F84. An extension makes it into the code for an auto fare meter.
Demonstrate it with a motor spinning a disk and an optical pickup.

Tiny Audio Amplifier using LM386.

Ultraviolet water purifier hooked up in a boat's water supply using a delay circuit.

Serial Link Monitor to troubleshoot communication through the serial port.

Serial Dongle - an interface between a microcontroller's pins and the serial port of the PC.

A nixie tube rolled off my desk onto the floor. The innards are quite interesting to look at,
the shaped electrodes all have equal area and they are designed not to obscure one another.

Old meter module using nixie tubes. I'm building it into a multirange voltmeter for my home lab.

Nixie Clock using cascaded 4017 cmos counters and transistor drivers.

Nixie Spinner - use to test nixie tubes, or as a display to show off if you got just one of a kind.

Frequency comparator to compare the frequencies of two signals that are nearly equal,
e.g. to check dropouts or noise on a clock line.

Time Delay and Undervoltage Cut intended for protecting the compressor on refrigerating equipment.

At times I need a source of slow pulses for testing counters and lamp chaser circuits.
A simple pulse generator circuit built around a 555 timer.

Counter and Lamp driver circuits for running lights with seventeen lamps. Uses two 4017 chips.

A manual EPROM Reader. Consists of switches and LEDs connected to a socket and little else.

A group of students wanted to demonstrate Amplitude, Frequency and Phase Shift Keying techniques.
Generate an eight-bit serial signal, send and receive it.

Valve based Signal generator circuit - Heathkit

One inch tube Oscilloscope from an old book.


RF and Ham related

When things go wrong, reduce complexity and get down to the basics.

An rf probe inside a ball point pen body using silicon diodes


Simple Circuits for kids

Clap Switch using transistors.


... and today's tip from my friendly manager is ...


Other files

Mobile phone disassembly - I am curious, so I take apart a Nokia 1100 just to see its insides.

Download Sound operated Remote control - clap_rem.zip - 947Kb
Turn on or off four appliances with two hand claps. The appliances have to be silent types, though.

Ventriloquist Horn - a silly idea on the halfbakery.

Edible Tickertape in top hat

CD4017 flash animation and suggestions for using the chip in practice.

Magic Cat Fur - Spoof Invisibility Idea, from the halfbakery.

Moonwalking Animation - another spoof from Bitmagic.

Welcome to the real world!

About myself - with a pinch of salt.

Web Ring page - Look, Ma, I can do it in colour, too!

A fairy tale back from the days of the Sinclair Spectrum - about lawyers and agreements
and things like that. From the 'Sinclair User', a computer magazine of those olden times.


Hardware and software working in harmony towards a common goal -
that's the description of a successful microcontroller project.

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