how to make propeller clock with Microcontroller AT89S51?
mohhhs
Posts: 4
I am doing a project for my junior year, so i chose the propeller colck but once i started i feel kinda lost.
First the microcontroller have built-in oscillator so that means i dont have to get RTC right?
second how fast the motor should be and which kind is prefered? i saw alot and i dont know which one is suitable.
Third are there any suggesstion from you guys, and what else i need beside the motor, microcontroler, power supply,and leds?
First the microcontroller have built-in oscillator so that means i dont have to get RTC right?
second how fast the motor should be and which kind is prefered? i saw alot and i dont know which one is suitable.
Third are there any suggesstion from you guys, and what else i need beside the motor, microcontroler, power supply,and leds?
Comments
I haven't added the code of schematics yet, but I plan to do so soon.
hehe, well yes, they DID call the P8X32A "Propeller", so I have little sympathy...
For what sounds like a Spinning LED display, you first need to define what you will show - Analog, Digital, or a mixture of both.
The simplest first step, would be 'analog arms', which would need a choice of 3 lengths (H:M:S), and you need to know the phase velocity to know when to fire each LED.
Motor speed is going to be hard to control accurately, so you will likely need to get a good handle on time/location per revolution, and divide that into at least 60 - ie a position sensor is needed.
You might like to try different ON times for H M S to give a 'narrower pointer' effect for Seconds
There are many good examples on Google, even RGB ones, that paint numerals on an analog clock.
Your more important decisions are going to revolve around "Power?"
Safest is a Disc profile, and it will be easiest if only power is coupled across the axle - brushes or magnets/coils ?
(ie mount the controller on the spinning disc)
Actually Setting the right time will be another challenge, perhaps a TV remote to a Std IR Receiver somewhere near the axle ?
A local RTC + some form of power, will keep time across runs. Sounds fun...
Google finds some interesting 'Printed Winding Motors', such as
http://www.mightyboyev.com/5kW%20Printed%20Circuit%20Motors.htm,
so some R&D effort put into a good PCB design, could make the rest easy...
Oh, and ask your Tutor to flip to the AT89LP52, or AT89LP6440, faster than the venerable 89S51, and with better timers. Exactly the Same Sw.
1) You will find it much easier to do with a Propeller chip.
2) You can come back here with a new thread "How to make a Propeller Clock with a Propeller". Then you will have the advice, encouragement and assistance of one of the most friendly and helpful groups on the net:)
In general though, you will need to spin your LED propeller at about 50Hz so that the flashing LEDs form a non-flickering image to the viewer.
You will need a sensor to detect the position of the Propeller so that you can flash the LEDs in synchronization. A Hall effect switch at the 12 o'clock position say.
Speed control is not critical if you can adjust the speed of LED cycling to match the rotor.
Think about how you will get power into the rotor.
Might want to include an IR receiver on the rotor in order to get commands into the clock as it rotates for time setting etc.