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In some point in the life of every electronics hobbyist the need to make a clock is borned, in my case it was about a month after I soldered my first part on a board, but back then I didn't have the right tools, parts and knowledge to do such a thing.
But after about 2 years I got all the things I didn't have back then and I was ready to make my first digital clock, and with all the LEDs I had left over from my 8x8x8 LED cube project I decided to make my own custom LED clock.
So join me and build your own custom LED digital clock powered by our favorite little micro-controller the Arduino.
But after about 2 years I got all the things I didn't have back then and I was ready to make my first digital clock, and with all the LEDs I had left over from my 8x8x8 LED cube project I decided to make my own custom LED clock.
So join me and build your own custom LED digital clock powered by our favorite little micro-controller the Arduino.
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Signing UpStep 1What Do We Need?
Here is what tools you will need to make this:
1) Soldering Iron.
2) Some solder wire.
3) Small needle nose plier
4) Small cuter
5) Wire striper
I made my clock with a stand alone arduino without the original board because I wanted to make a finished project.
Now here are the parts you will need to make the clock:
1) 130 LEDs.
2) 15 2N4401 transistors.
3) 20 1K resistors.
4) about 10 resistors for the current protection(more detail in step 2). I used 150Ohms.
5) DS1307 real time clock IC.
6) one coin cell battery holder.
7) 4 Tact switches.
8) Prefboard (you would like to get along one for the display about 8inch*3inch)
9) ATMega328 with arduino bootloader.
10) A programmer for programing the chip.
11) 7805 voltage regulator.
12) 16MHz crystal.
13) two 22pF caps.
14) 28 pin IC socket for the ATMega328.
15)10 uF cap.
16)0.1 uF cap.
17) 4017 counter
18) 32.768KHz crystal
1) Soldering Iron.
2) Some solder wire.
3) Small needle nose plier
4) Small cuter
5) Wire striper
I made my clock with a stand alone arduino without the original board because I wanted to make a finished project.
Now here are the parts you will need to make the clock:
1) 130 LEDs.
2) 15 2N4401 transistors.
3) 20 1K resistors.
4) about 10 resistors for the current protection(more detail in step 2). I used 150Ohms.
5) DS1307 real time clock IC.
6) one coin cell battery holder.
7) 4 Tact switches.
8) Prefboard (you would like to get along one for the display about 8inch*3inch)
9) ATMega328 with arduino bootloader.
10) A programmer for programing the chip.
11) 7805 voltage regulator.
12) 16MHz crystal.
13) two 22pF caps.
14) 28 pin IC socket for the ATMega328.
15)10 uF cap.
16)0.1 uF cap.
17) 4017 counter
18) 32.768KHz crystal
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www.alsatel06@yahoo.fr
plz
The script you added to upload to the atmega328 does not work with Arduino 1.0.
Can you make an updated version of the code.
There's an outdated standard library in his libraries called WProgram.h and in the original program.
All you do is edit the name to Arduino.h which is the name of the new standard library, but to do this you need an editor program like microsoft's visual studio to open, edit and save the new libraries. Once you've done that it should compile with no issues in 1.0.
Thanks
zahidhasan19@gmail.com
dave_steven1102@gmail.com
thanks!
Thanks Syst3mX.
please respond soon
Thanx
Thanks
ph-heema@hotmail.com
sorry but just one more thing how many days it took from you to make it ?
membrane_owner@yahoo.com
The calculation is simple and gos like this :
R=(Vcc-Vled)/(Iled*3)
R= the resistor value
Vcc = The voltage that is supplied
Vled = the forward voltage on the LED
Iled =the current the LED takes
Thanks again.
first I had these resistors on hand and second my blue LEDs was super bright so I had to limit the current even farther.
The real value I needed to use to get the maximum brightness is about 47 Ohms.
R=(5V-2.2V)/(20mA*3) = 2.8V/60mA = 46.666Ohms
We round it up to a value we can get and take that resistor.
You can find very detailed instructions on how to use the board.
The 10uF and 0.1uF capacitor is polarized right?
Dumb question, but how do I tell which pin is the positive pin?
The 10uF cap has a white strip along its body and this indicates the negative pin.
Also does the voltage rating have influence on the circuit?
Btw.
If the below is a description of a capacitor.
Description
CAPACITOR CERAMIC, 22PF, 50V, C0G/NP0, Radial
Dielectric Characteristic:C0G / NP0
Capacitance:22pF
Capacitance Tolerance:± 5%
Voltage Rating:50VDC
Series:Mono-Kap
Capacitor Case Style:Radial Leaded
No. of Pins:2
RoHS Compliant: Yes
How can I tell if that is a non polar capacitor or polar?
Let me see if I understand your schematic.
Correct me if I'm wrong in any way, please.
There are a total of 6 digits and 4 dots.
Each digit is broken down into 7 segments.
First:
The anode pin of each led in a segment is connected with the 150 ohm resistor and the resistor is connected to the emitter pin of the 2N4401 transistor. A total of 7 2N4401 transistors are used for the 7 segments. Is all that correct?
Second:
The cathode pins in a single digit are all soldered together and is then connected to the collector of another 2N4401 transistor. Since there are 6 digits this takes 6 more 2N4401 transistors. Is that all correct?
Last:
The 4 dots are split into the 2 upper and 2 lower led.
So 2 more t2N4401 transistors are needed.
The emitter of the 2N4401 transistor is connected to the anode pin of the 2 LEDs and the cathode pin of the 2 LED are then connected to a 150 ohm resistor and then grounded.
I have a question on the last one.
Why are the resistors connected on the cathode pin of the LEDs that are used as dots and not the anode pin?
like in the 7 segments the resistors are connected to the anode pins.
There is no difference in the way of the resistor connections
I changed it a little bit because it was easier to solder in my case.
The arduino platform is very popular so it's not that hard to find