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Hobby Electronics:
PIC -- Based Analog/Digital Alarm Clock with
Voice-Recordable Alarm

Clock Face Clock Side

The idea here was to have an alarm clock with a rerecordable alarm sound, to afford some variety to the waking-up ritual and to provide respite from the insufferable beepings and raspings of usual alarm clocks. The basic concept is easily realized with a microprocessor, an LCD display module, a voice recorder chip, and some audio circuitry, and along the way I figured I could improve the appearance by adding a stepper motor to drive an analog face. The result is a basically totally trivial piece of circuitry enclosed in an ever-so-slightly less trivial mechanical housing, and with the schematics and assembly code here you too can build one, in no time, for fun and -- well, probably not for much profit.

Before I forget (it's so easy to take free software for granted these days...) let's be sure to acknowledge some of the outstanding open-source tools without the free availability of which this project, and so much else I have ever done, would have been prohibitively expensive to complete:

Table of Contents

  1. A brief description of how it works.
  2. A schematic of the circuit.
  3. Some pictures of the constituent parts before assembly.
  4. The assembly language code for the PIC microprocessor at the heart of the clock.

How It Works

The innards of this thing are really so trivial as to render a 'how it works' section somewhat superfluous, but here are the salient points.

Circuit Schematic

Hooray for gschem! Click here or click the image below for a larger view.

Clock Schematic


Circuit board (component side). PCB Component Side
Circuit board (solder side). PCB Solder Side
Stepper motor mounting, view 1 Motor View 1
Stepper motor mounting, view 2 Motor View 2
My PIC programmer, which I built following this guy's design. PIC Programmer

Assembly Language Code

Homer Reid: Analog/Digital Voice-Recordable Alarm Clock, by Homer Reid
Last Modified: 04/16/17