Propeller Clock Mechanically Scanned LED Clock using PIC16C84

This is the first clock I ever built. I’ve built a few LED signs, but they get boring because I already know the message.

How this clock works:
A motor spins the “propeller”, and a small microprocessor keeps track of time and changes the pattern on seven LEDs with exact timing to simulate a 7 by 30 array of LEDs. It is an illusion, but it works nicely.

Propeller Clock

If you want to build this clock, you will need a few things, including:
Skill with motors and mechanical things.
Prior electronic experience.
A dead VCR or floppy drive or other source of a suitable motor and miscellaneous parts.
A programmer that will program a PIC16C84 or 16F84 microprocessor.

I have provided (almost)everything else:
The Next Page with drawings and plans.

mclock.txt A full description how to build it.
mclkpart.txt The parts list.
mclock8.asm The source code in Microchip MPASM format.
mclock8.hex The hex code ready to load into a PIC16C84 or 16F84 chip.
mclksch2.gif A large and very readable schematic diagram.
mclkmoto.gif A drawing of the modifications to the motor.

If you can’t get that kind of motor, you can use the motor from an old disk drive. This page has a lot of pictures and will take some time to load. If you use a disk drive motor or any other DC motor with brushes 180 degrees apart, you’ll need the slightly revised code:
mclockt3.asm The source code.
mclockt3.hex The hex code ready to put in a chip.

If you don’t have any way to put the program into a PIC 16C84 or 16F84 chip, you can build your own programmer.

Printed Circuit Board Layout for a version of the clock.

The hardware design and software are covered under the GNU General Public License.


For more detail: Propeller Clock Mechanically Scanned LED Clock using PIC16C84

About The Author

Ibrar Ayyub

I am an experienced technical writer holding a Master's degree in computer science from BZU Multan, Pakistan University. With a background spanning various industries, particularly in home automation and engineering, I have honed my skills in crafting clear and concise content. Proficient in leveraging infographics and diagrams, I strive to simplify complex concepts for readers. My strength lies in thorough research and presenting information in a structured and logical format.

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