Seven Segment LCDs? Answered

Http://i00.i.aliimg.com/photo/v0/325133078/7_segment_LCD_panel.jpg Has anyone had any luck hooking up seven segment lcds to their arduino's? These have 4 seven segment digits, a :, and an am/pm display. They have less than 28 pins.

Question by Michael_Bell 7 years ago  |  last reply 7 years ago


Seven Segment LED/LCD displays?

Does anyone know a good tutorial on how to use these? Thanks!

Topic by perkinsb1024 11 years ago  |  last reply 11 years ago


7 segment display nsn64r

Hi!Is there anyone having data on nsn64r pinout ? I found a few of them but no pinout instructions.Thanks

Question by gonzo_one 4 months ago  |  last reply 4 months ago


LED display

I have a Gill ultrasonic wind gauge which transmits data intermittently (after each race) showing the actual windspeed -9.9 to +9.9 range It outputs the data at 9800/7/even/1 the data is in a series of bytes with the data in the middle of the series I dont know what the other bytes are for I want to display the data automatically in a LED (segment) display, the display changing each time the gauge transmits new data will an 'ordinary'LED controller allow me to do this? thanks david cooke 

Topic by DavidC69 3 years ago  |  last reply 3 years ago


How to I display voltage on a 7 segment display?

Okay, I've never actually come across this before or needed to do this but now i come to it, i realise I am really lost to it. What i need to do is display a 3 digit (hundreds eg. 342) number on three 7 segment displays. So pretty much I just need a 3 digit voltage read-out to be incorporated into a portable design. I've been looking around and have come across the Analog to Digital converters, and understand how they work, but I'm not sure how to incorporate them or to put it to any use. So if anyone knows or has a schematic or any information I could work off, please help. :)ThanksPyroten

Question by pyroten 9 years ago  |  last reply 6 years ago


7 segment led display driver help?

7 segment sed driver/decoder circuit helpEMAIL FLAGIve looked all over, and have already tried 3 circuits, but none work. They have either the wrong ic, wrong led display, etc. So, I want to make a circuit that, by using a decoder, I can flip 4 dip switches and make the display make certain numbers. I have a 7447 ic, common cathode led display, but I can only either find a circuit with a 7447 and a common anode, or a circuit with a common cathode but a different decoder (a latch/decoder/driver). Here is the first site I tried:http://www.allaboutcircuits.com/vol_6/chpt_7/9.htmlAnd when I finally flip the switches, nothing happens even though I made it exactly as shown. But it has a CMOS, so thats probably a big problem. I also tried this site:http://www.atilim.edu.tr/~hkar/lab5.htmBut it has a common anode, and when I tried it it didnt work. I have exactly ELS321HDB. And I have a power unit that can go from 5 - 18 volts. Can anyone show me how to make this? Im not too good yet at reading circuit diagrams, because I seem to make it way more complex then it should be.

Question by 101yummYYummy101 10 years ago


0-12V Digital Display?

Here's what I need, and haven't been able to figure out how to do it: I designed a motor speed controller that runs a 12V fan.  Speed control is via PWM through a 50K linear Potentiometer. I need to be able to read the percentage of run voltage ie: 0V=0%, 6V=50%, 12V=100%.  I want to display this on 3 7-segment LED displays. Anyone with insight would be greatly appreciated. Brian

Question by BrianAriz 3 years ago  |  last reply 3 years ago


Help with Arduino programming for LED display

What I want to do is keep score with my coin soccer game. I will have 2 metal contacts in the goals that when a coin goes through it will break contact and send a signal to the Arduino having the contacts allways HIGH and then when its LOW, it changes an 7 segment LED. I am very new to programming and the C language. I think I can write the whole IF and ELSE statements but I don't know how to make the LED display change. I need the LED display to change after getting the signal from my Arduino by going up one number. It is a single 7 segment display. Can someone help me with the code for that? Thanks in advance.

Topic by Wally_Z 7 years ago  |  last reply 7 years ago


How should I build a digital "counter with a seven-segment display?

I have a seven segment LED display and I would like to build a digital counter that will increase or decrease the number value displayed on the display when I press a button (a button for counting up and a button for counting down). So I would like to be able to press one button to increase the displayed value (1, 2, 3...) and then press a different button and have the value decrease (9, 8, 7...). Thanks for the help!

Question by MadMechanic 9 years ago  |  last reply 6 years ago


common anode and common cathode differences in 7segment display

What are the changes need to do when using common anode seven segment display instead of common cathode seven segment display. hint:use transistors?

Question by nethmi.amanda.3344 4 years ago  |  last reply 4 years ago


7 segment sed driver/decoder circuit help

Ive looked all over, and have already tried 3 circuits, but none work. They have either the wrong ic, wrong led display, etc. So, I want to make a circuit that, by using a decoder, I can flip 4 dip switches and make the display make certain numbers. I have a 7447 ic, common cathode led display, but I can only either find a circuit with a 7447 and a common anode, or a circuit with a common cathode but a different decoder (a latch/decoder/driver). Here is the first site I tried:http://www.allaboutcircuits.com/vol_6/chpt_7/9.htmlAnd when I finally flip the switches, nothing happens even though I made it exactly as shown. But it has a CMOS, so thats probably a big problem. I also tried this site:http://www.atilim.edu.tr/~hkar/lab5.htmBut it has a common anode, and when I tried it it didnt work. I have exactly ELS321HDB. And I have a power unit that can go from 5 - 18 volts. Can anyone show me how to make this? Im not too good yet at reading circuit diagrams, because I seem to make it way more complex then it should be.

Question by 101yummYYummy101 10 years ago  |  last reply 7 years ago


Where can I find large seven segment displays?

My neighbor wants me to make a scoreboard for his ping pong table, but I'm having difficulty finding something to use as the display.  Seeed Studio has some, http://www.seeedstudio.com/depot/7-Segment-Display-8-Inches-Red-p-1194.html, but they come in individual segments.  Sparkfun has some as well, but they're on a tan colored PCB.  Where's the cheapest place to find 6"+ displays on a black background?

Question by furrysalamander 4 years ago  |  last reply 4 years ago


A brighter speedometer? LED display?

My current speedometer uses the same type of display that you may find on a solar-activated calculator or cheap alarm clock (the ones that display black letters on a grey background). problem is, I cant see it in bright sunlight! Is there is a way to make a speedometer with my own set of 7-segments displays that use LEDs, or if I could convert my current one to using them?

Question by phephq 8 years ago  |  last reply 8 years ago


Fixing a 5 character seven segment display clock

This is a count up race clock that fell due to high winds and has stopped working. It is a springco athletics model 2710A. I have already tried respecting and reconnecting all the non soldered pieces of this display. The main chip on the board is a PIC16F887 with 20 pins. Each display is connected by a single ribbon cable with 20 pins and there are jumpers on each display labeled 1-6(presumably for the character placement in the display). If I cannot find a way to fix the current hardware I would like to replace the control board with an arduino that can do the same thing but I do not know how to wire the display to the arduino nor what model to use. Any suggestions are welcomed.

Question by Tsall1698 2 months ago  |  last reply 2 months ago


Trying to figure out how to make a 7 segment LED show random

Hey everyone I am working on a project where I would like to install one of these: http://cgi.ebay.com/10pcs-0-8inch-7-segmen...=item483fd1c0dd and have it display completely random things (dont even have to be numbers) How could I possible go about doing this? I would like to try and make it as simple as possible, Thanks!

Topic by snake126 8 years ago  |  last reply 8 years ago


LED Scoreboard

Hi, My name is Tom, i am new to instructables and to advanced electronics in general. I want to make a LED Scoreboard which can display two scores (each on a different display) i also had an idea how to make the display. The idea is placing red LED's under plastic cutouts of a classic 7 segment digit board (ilustrated on the picture), the problem is that other than that i have no idea where to start and nor what to look for so any help is appreciated. P.S. I can solder, but that's about it that i can think will be useful to this project. Thanks in Advance  

Topic by Loonzard 5 years ago  |  last reply 5 years ago


Read from a 7-segment display LCD

Hello everyone. Suppose you have some device with a numeric LCD display with some 7-segment digits (i.e. a digital scale), and you want to hack it in order to read out electronically (for example with an rs232 connection), while preserving functionality of the thing. How you would do that?

Topic by avvelenato 3 years ago  |  last reply 3 years ago


20 year old 7 segment 9 digit led display- PLEASE HELP TO FIGURE OUT PART NUMBER AND DATASHEET?

URGENT HELP APPRECIATED I have a 20 year old 7 segment 9 digit led display, i cannot figure out the part no. Here's is what is written in the back of it- (NSA 520 DCCB VO 0179-A) it has 9 digits, a segment below every digit, 7 segment per digit, 18 pin holes

Question by polkijain 5 years ago  |  last reply 5 years ago


How to make a 7 segment clock? Answered

Hi! i have 6 X 7 segment displays ( i think common annode) hanging around and i was wondering if i could make an clock with hours minutes seconds and an LED or 2 LED's that blinks every second, without an arduino. i do have an arduino for programming but i rather use other parts so that i can use my arduino for other projects. who can help me? Thanks!

Question by ingkiller 4 years ago  |  last reply 4 years ago


Pin allocations on 4 digit, 7 segment LED display... Answered

Hi, I have recently bought a 4 digit, 7 segment LED display to hook up to my arduino and am unsure of what pin does what. I have a green KINGBRIGHT (2009-34) CA56-216WA (M3) and can not find it on the kingbright website. Also, while I was looking at the other models I noticed that some pins were labeled DP. If anyone can be of any assistance it would be greatly appreciated. Thanks again!  Ari

Question by anonymouse197 8 years ago  |  last reply 8 years ago


I would like some assistance in designing a digital LED display vacuum/boost gauge for a turbo application. Answered

Hello!   I'm new here. I would like some assistance in designing a digital LED display vacuum/boost gauge with both a linear LED display as well as two seven-segment display modules.   I plan to use a standard automotive MAP sensor to provide the -30Hg to  +30psi signal.   What I envision is having the two seven-segment displays sit next to a row of 28 green LEDs for vacuum to -28Hg, 7 yellow LEDs for pressure from +1psi to +7psi, and 8 red LEDs for pressure from 8psi to +15psi that light up incrementally as the pressure increases or vacuum increases from a center point of zero (clear LED always on).  The problem is that I have absolutely NO idea of where to start other than the layout of the LEDs.  So any help would be appreciated. Thanks! Skullmaster20  (Chris) Edit -----  This is a drawing of what I'm trying to create, and a picture of what I'm going to replace.

Question by skullmaster20 9 years ago  |  last reply 9 years ago


new to arduino, want to run a dual display for 2 sensors

I'm new to the Arduino community.  wanting to set up a dual radar setup with 2 ultrasonic sensors,  (Ultrasonic Sensor Module HC-SR04), and outputting to a pair of 7 segment displays ( two 7 segment displays each).  I've found a code to do a single could use a lot of help to output two at the same time, basically 2 lanes without 2 units.  im using an arduino mega, ordered a unor3 and hopefully it can be made to run on one or the other. code is as follows: /* HC-SR04 Sensor    The circuit:     * VCC connection of the sensor attached to +5V     * GND connection of the sensor attached to ground     * TRIG connection of the sensor attached to digital pin 2     * ECHO connection of the sensor attached to digital pin 4  */    /*  This is a radar ping sensor that calcultates the speed of an  object traveling away or towards the sensor. I took some of this  code for the HC-SR04 Sensor implementation by Tautvidas Sipavicius. The rest  is original code from me. I know that the seven segment display  code is not the best to look at or the most optimized but it  serves its purpose just fine and is easy to understand.    Written by Matthew Ladd  */   const int trigPin = 2; const int echoPin = 4;   void setup() {   // initialize serial communication:   Serial.begin(9600);   //First 7 segment (ones place)   pinMode(30,OUTPUT);//F   pinMode(31,OUTPUT);//G   pinMode(32,OUTPUT);//E   pinMode(33,OUTPUT);//D   pinMode(34,OUTPUT);//C   pinMode(35,OUTPUT);//B   pinMode(36,OUTPUT);//A   //Second 7 segment (tens place)   pinMode(37,OUTPUT);//F   pinMode(38,OUTPUT);//G   pinMode(39,OUTPUT);//E   pinMode(40,OUTPUT);//D   pinMode(41,OUTPUT);//C   pinMode(42,OUTPUT);//B   pinMode(43,OUTPUT);//A } void zerofirst(){   digitalWrite(30,LOW);   digitalWrite(31,HIGH);   digitalWrite(32,LOW);   digitalWrite(33,LOW);   digitalWrite(34,LOW);   digitalWrite(35,LOW);   digitalWrite(36,LOW); } void onefirst(){   digitalWrite(30,HIGH);   digitalWrite(31,HIGH);   digitalWrite(32,HIGH);   digitalWrite(33,HIGH);   digitalWrite(34,LOW);   digitalWrite(35,LOW);   digitalWrite(36,HIGH); } void twofirst(){   digitalWrite(30,HIGH);//F   digitalWrite(31,LOW);//G   digitalWrite(32,LOW);//E   digitalWrite(33,LOW);//D   digitalWrite(34,HIGH);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void threefirst(){   digitalWrite(30,HIGH);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void fourfirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,HIGH);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,HIGH);//A } void fivefirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,HIGH);//B   digitalWrite(36,LOW);//A } void sixfirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,LOW);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,HIGH);//B   digitalWrite(36,LOW);//A } void sevenfirst(){   digitalWrite(30,HIGH);//F   digitalWrite(31,HIGH);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,HIGH);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void eightfirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,LOW);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void ninefirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,HIGH);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void zerosecond(){   digitalWrite(37,LOW);   digitalWrite(38,HIGH);   digitalWrite(39,LOW);   digitalWrite(40,LOW);   digitalWrite(41,LOW);   digitalWrite(42,LOW);   digitalWrite(43,LOW); } void onesecond(){   digitalWrite(37,HIGH);   digitalWrite(38,HIGH);   digitalWrite(39,HIGH);   digitalWrite(40,HIGH);   digitalWrite(41,LOW);   digitalWrite(42,LOW);   digitalWrite(43,HIGH); } void twosecond(){   digitalWrite(37,HIGH);//F   digitalWrite(38,LOW);//G   digitalWrite(39,LOW);//E   digitalWrite(40,LOW);//D   digitalWrite(41,HIGH);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void threesecond(){   digitalWrite(37,HIGH);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void foursecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,HIGH);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,HIGH);//A } void fivesecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,HIGH);//B   digitalWrite(43,LOW);//A } void sixsecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,LOW);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,HIGH);//B   digitalWrite(43,LOW);//A } void sevensecond(){   digitalWrite(37,HIGH);//F   digitalWrite(38,HIGH);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,HIGH);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void eightsecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,LOW);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void ninesecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,HIGH);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } long distanceOverTime(long first,long second){  return ((first-second)/.1)*.0223693629;//taking cm/s to mph } long holder;//store the cm from last time through loop. long temp;//used to store the speed value after changes int counter; void loop() {   // establish variables for duration of the ping,   // and the distance result in inches and centimeters:   long duration, inches, cm;   int tens;   int ones;   long Speed;   // The sensor is triggered by a HIGH pulse of 10 or more microseconds.   // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:   pinMode(trigPin, OUTPUT);   digitalWrite(trigPin, LOW);   delayMicroseconds(2);   digitalWrite(trigPin, HIGH);   delayMicroseconds(10);   digitalWrite(trigPin, LOW);     // Read the signal from the sensor: a HIGH pulse whose   // duration is the time (in microseconds) from the sending   // of the ping to the reception of its echo off of an object.   pinMode(echoPin, INPUT);   duration = pulseIn(echoPin, HIGH);     // convert the time into a distance   inches = microsecondsToInches(duration);   cm = microsecondsToCentimeters(duration);   Speed=distanceOverTime(holder,cm);   holder=cm;//after speed caclulation so take the cm value for another calculation   Speed=abs(Speed);   if(Speed!=0 || counter==10){     temp=Speed;     counter=0;   }else{     counter++;   }   if(temp>=100){    zerofirst();    zerosecond();   }else{     ones=temp%10;     tens=temp/10;   }   if(ones == 0){     zerofirst();   }else if(ones==1){     onefirst();   }else if(ones==2){     twofirst();   }else if(ones==3){     threefirst();   }else if(ones==4){     fourfirst();   }else if(ones==5){     fivefirst();   }else if(ones==6){     sixfirst();   }else if(ones==7){     sevenfirst();   }else if(ones==8){     eightfirst();   }else if(ones==9){     ninefirst();   }   if(tens == 0){     zerosecond();   }else if(tens==1){     onesecond();   }else if(tens==2){     twosecond();   }else if(tens==3){     threesecond();   }else if(tens==4){     foursecond();   }else if(tens==5){     fivesecond();   }else if(tens==6){     sixsecond();   }else if(tens==7){     sevensecond();   }else if(tens==8){     eightsecond();   }else if(tens==9){     ninesecond();   }       Serial.print(inches);   Serial.print(" in, ");   Serial.print(cm);   Serial.print(" cm, ");   Serial.print(Speed);   Serial.print(" mph");   Serial.println();     delay(100); }   long microsecondsToInches(long microseconds) {   // According to Parallax's datasheet for the PING))), there are   // 73.746 microseconds per inch (i.e. sound travels at 1130 feet per   // second).  This gives the distance travelled by the ping, outbound   // and return, so we divide by 2 to get the distance of the obstacle.   // See: http://www.parallax.com/dl/docs/prod/acc/28015-PING-v1.3.pdf   return microseconds / 74 / 2; }   long microsecondsToCentimeters(long microseconds) {   // The speed of sound is 340 m/s or 29 microseconds per centimeter.   // The ping travels out and back, so to find the distance of the   // object we take half of the distance travelled.   return microseconds / 29 / 2; } again, all your help and thought are appricated

Topic by herb1977 1 year ago  |  last reply 1 year ago



How do I use a Common Anode 7-Segment LED? Answered

I have a SA23-12EWA Common Anode 7-Segment LED and I can only get the decimal point to light up. How do I connect it so that the other segments light up?

Question by powerman666 6 years ago  |  last reply 6 years ago


how to make tachometer with 7 segment display for single cylinder 2 stroke 6v ignition..can anyone help me? Answered

I found a diy project from https://www.instructables.com/image/FU19QM5GH4NN2QX/Building-the-circuit.jpg but i want to use only 3 led(7-segment display) instead  of  4 led.. and another problem is this circuit only fit input signal from 12v ignition 4 cylinder ( car ), but mine is 6v single cylinder 2-stroke( motorcycle ).. what i have to modify so than i can make a circuit that can use 6v signal to the ic and only use 3 led(7-segment display.. can any give an opinion or some one that have done this to help..im not to good with electronic but i understand english. :-)

Question by kill_them_now 7 years ago  |  last reply 7 years ago


Arduino connect 6 Digit 7 Segment LED Display

Hey guys, so I have been looking at various photo booths on Instructables and would love to create my own one using a Arduino and a Raspberry Pi. To get this in place i would like to know which Arduino can run this "rig". I will have 7 x 7 segment LEDs, Camera Remote to trigger camera, Raspberry Pi to receive, process print and show the images, printer to print the images(well this will be connected to the rPi, and a lcd to preview camera view before picture is taken. 2 Big buttons to trigger sequence and to print the last 4 photos onto 1 jumbo print. *NOTES* 6 of the 7 segments will be multiplexed for the top display. 1 x 7 segment will only count the amount of photos left (4-3-2-1-0) for every "session" LCD will be connected to the camera only for before snap preview. The press off a button will start the "session" The count down on the main display (6x7Segment) will go like 5 - 4 - 3 - Pose - Smile then the picture is taken. the single 7  segment will then go from 4 to 3 and the main display will start again from 5..... While this is running the LED in the button need to be off After all 4 photos has been taken the rPi need to get a signal to get the images (not sure how to do this either) process them en make them print ready. If the print button is pressed within 10 - 15 seconds the image will print out. ONLY WHEN THE BUTTON IS PRESSED.(This button will light up for this 10-15 seconds while the start button if off) All images need to stay on the device for later printing and saving on a disc. After the 10-15 seconds the first light need to come on again for next "session" I have no idea how to start this. Any help in this would be great. I am a wedding photographer with little to no knowledge in electronic circuits. But i know from reading (a lot this week) that i might need some extra parts to not damage the Arduino etc. Thanks in advance.

Topic by DragonzA 4 years ago  |  last reply 4 years ago


stop 7-segment from ghosting?

I'm working on a simple arduino 7 segment driving circuit. (It also has a led bar-graph that displays binary numbers but that part is working fine.) When I get the display working I might make an instructible out of it. Here's the basic layout: -using this 8 segmet 4 digit common cathode display. -arduino controls what segments are on via 74HC164 8-bit Serial Shift Register -shift register controls an array of 8 PNP transistors with base and pull-up resistors -transistors connect to display anodes through resistor array -display cathodes (common for each digit) connected to array of 4 PNP transistors with base and pull-down resistors  -PNP transistors controlled by arduino. (I will post the schematic shortly.) In software, to display a four digit number, I shift the pattern for a given digit to the shift-register, which in turn turns on the PNPs for the corresponding segment anodes. I then turn on the NPN for that digit's cathode. I delay for a few milliseconds, then turn the NPN off, shift the next digit in, and turn the NPN for that digit on. Rinse and repeat. It works fine but the segments that should be off are at about 1/2 brightness, making all the digits look like eights. Even the DP looks like it's on and I'm not turning it on anywhere. Do I need pull-down resistors for the anodes or something? What's going on here?

Question by Vick Jr 7 years ago  |  last reply 7 years ago


Dear Instructables, how would i go about creating a 3 digit up counter that reacted to 3 buttons of different values?

Basically i'm designing and making a scoreboard for a rugby match for an a-level course. I'll explain the buttons of different values first, in rugby (for those who don't know) there are 3 different ways that the score can increase 2 points (conversion), 3 points (penalty, drop goal) and 5 points (try). I already know how to make a circuit to increase in 1's but i wasn't sure if you could do it with 3 different values in the same circuit. I was thinking of using a 4024 seven bit counter connected to a bcd to led decoder then to 7 segment led displays. is there anything out there which could make my job easier or do you have any advice or could you help me? Thanks alot, Hrimiller Edit: 4024 seven bit counter connected to a bcd to led decoder then to 7 segment led displays

Question by hrimiller 6 years ago  |  last reply 6 years ago


Arduino LED Clock RGB?

This is probably too big of a project for a first timer.I do not own a Arduino but plan to get one in the next few weeks or so or whenever Make releases the Getting started with Arduino KIT Again. I'm planing my project so that I can work on it with the fewest problems. I had the idea from 5volts fire extinguisher striking clock. My question is that is there a way that I can use RGB LEDs? I just wanted to use RGB LEDs instead of 7 segment displays but use the same layout and have a nice color fade with the time.http://www.5volt.eu/archives/16 Look for his schematic and code.The schematic shows a easy way to hook up a 7 segment display to an Arduino. I'm just not sure how to control another color. I was thinking maybe 3 BU2090's going from pins 12 an 13 and using the Arduino to control the power going to them. 5volt suggested triple multiplexing but I'm not too sure on how to do that. Also I'm not sure on common anode or common cathode LEDs?(I don't want to use 54 of each color.)As for clock face I was thinking like in the picture. 2 LEDs per segment, 8 for the colon. That is a 24"x12" box using 10mm LEDs. Center to center LED height is 7.125"Any help would be appreciated I have hit a snag trying to figure this out.

Topic by Rob K 10 years ago


Timer Mod question

Anyone know how or if it's even possible to mod a countdown timer like this one:http://www.goldmine-elec-products.com/prodinfo.asp?number=G15871to have an led segment display like this: http://www.allelectronics.com/images/gold/full/SDA-801.jpgwould i just need to take off the old time and solder the segments of the new display accordingly?

Topic by mrshow555 11 years ago  |  last reply 11 years ago


Multiplexing more than 100 7segment LED displays with a microcontroller

What are the multiplexing techniques to interface about 100 7segment displays to a 8-bit microcontroller (say 8051). If I hook up a row of decoders to the control pins of the display array on a common bus, I guess I might acheive it. But I doubt if there would be any flicker while doing so. Say for example, If I have 64 pairs of 7seg digits to be controlled, I may do a round-robin multiplex to the tune that each pair is ON for about 1ms in every 64 ms. Will that be possible, given that the duty cycle and frequency are of that order? Thanks for your invaluable response. Regards, Ather

Topic by blue_flare 11 years ago


How can I apply a calculation to a frequency counter?

I am trying to find a way to convert frequency (as in cycles per second (literal cycles of a wheel)) into speed. I've found schematics and code for a frequency counter, but I want to be able to display the actual speed in MPH in LEDs. The calculation is simple enough to do - I just need to know if there is a way that I could covert the output of a frequency counter to MPH by way of some calculation, and if so, how.  essentially, I want to learn how to program, say, a PIC micro to read how often a reed switch is closed, then translate that into a readable speed on 7-segment leds. where should I start? what kind of chip should I use? Where do I learn to code? I am pretty much lost thanks for reading

Question by phephq 8 years ago  |  last reply 8 years ago


I need an arduino temperature and humidity sensor WITHOUT Wifly

Hi all, I am looking to make an arduino temperature and humidity sensor with an onboard display. I am fairly new to arduino but do have electronics experience. I am looking to just look at the thing and be able to read the temperature and humidity without having to go into the other room and kick someone off of the computer. I currently have an arduino uno, a RHT03 Humidity and Temperature Sensor, several 7 segment displays, enough LEDs to make a led matrix or clock type setup, and a Nokia 5110 graphic LCD with arduino board (which I could remove if needed) found at https://www.sparkfun.com/products/10773  Any help would be greatly appreciated. Thank you all. Professorred

Topic by professorred 6 years ago  |  last reply 6 years ago


FULL CODE FOR A 24 * 9 LED MATRIX

Https://www.instructables.com/id/Make-a-24X6-LED-matrix/ I have successfully made a 24 * 9 led matrix following the instructions on above link, which when I use with an arduino from a serial monitor I am able to display a scrolling text. However l want when one types a text and or numbers -maximum seven, they should be displayed permanently or stationary except of course if one decides to change the text and send again from the serial monitor. Kindly can someone send a full code for the task. I suppose you will change and update the code from the above link. My email address is : simonnjoroge2000@yahoo.com

Topic by NJORO1975 1 year ago  |  last reply 1 year ago


Screen to use for HUD in goggles?

I'm using a GPS module and Arduino to make a Heads Up Display for a pair of old ski goggles I have. What kind of display can I use to show my speed? I just need two digits (but 2 7-Segment LEDs would probably be too thick). Any suggestions are welcome!

Topic by Login258 10 years ago  |  last reply 7 years ago


Digital Logic Design Project Combinational Lock?

In this project you are required to design a 4 digits combination lock (not using arduino)  The project is such that it can be reconfigurable i.e. there should be an option that we can change the password of the lock at run time. Input to the system is from the hex keypad. Output of the system is ‘open’ and ‘close’ words displayed on a seven segment I used registers,flip flops, mux ,comparator  but couldn't get the desired result

Question by r_sammad 4 years ago  |  last reply 4 years ago


Problems with the 4511b IC chip??

SO i made a circuit which is a binary adder(using the 4008b) that adds numbers in binary and then passes on the result to a 4511 IC(its a BCD to 7 segment decoder),so basically it adds numbers in binary and displays them in decimal .It seemed to work fine for a while but then suddenly when i tried adding 0011 +0001(3+1) in binary ,it still displayed 0 and then i tried tapping the battery for a second or two and then suddenly the seven segment display shows 4 .The circuitry is all fine and right .but do i have to connect latch enable(pin 5) pin of the Ic?.Both the IC's run on a 9v battery and for the 4511 decoder IC i used 33k pull down resistor .Is my pull down resistor value for the 4511 IC too high ?The binary adder part seems to work very well,its the bcd to 7 segment decoder IC part that I'm very much concerned about.Is there too less power for both the chips to run on?I've not got a single idea at all .so, >PLS help me if you can.

Question by Strontium 5 years ago  |  last reply 5 years ago


24 x 24 LED Matrix Project

I would like to share with you all an awesome project and some doubts and questions related to the same. This is a 24 x 24 LED Matrix project taken from here. All the data is taken from the same link. 24×24 LED dot matrix -->   This is pretty old circuit but I found it interesting to describe here. 24×24 LED display is formed by using 9 8×8 Dot LED matrix displays, that are connected to AT90S2313 MCU. MCU scans an indicator lines in series. Special PC program is written which allows drawing images on screen and transfer them via COM port to device. You can send images in series what gives an animation effect.   Circuit is was built using obsolete AT90S2313 MCU which can be replaced by Attiny2313 MCU with minor modifications of firmware. To make program work you event don’t need to connect device to computer COM port. You can store images in other master MCU EEPROM memory Each received byte from UART is immediately sent to 8 LEDs, second byte to next 8 LEDs and so on. Bytes has to be sent one by one without delay. USART is working at 115200 baud, 8bits, no parity. ---------------------------------------------------------------------------------------------------------------------------------- THE PROBLEMS >1>I really dont know if the circuit is good or not tell me if it is going to work. >2>I cant get 8x8 dot matrix displays so i am going to normal leds to a 24x24 one. >3>I have never worked with bus before (the bold red lines in the circuit) so i dont know how to connect it. >4>The schems are segmented i am finding it hard to figure out how to connect some of the segments. >5>Also i need to know how to hook it up to my pc. >6>I have never done programming so i need to know how to program the ic. THANK YOU I couldnt get the images uploaded nicely so i linked them. 1 2  

Topic by science_freak 8 years ago  |  last reply 8 years ago


ICL7107 and LM35 based 7-segment thermometer

I'm trying to create a digital centigrade thermometer based on an ICL7107 3 1/2 digit 7-segment driver/ADC and an LM35 linear centigrade temperature sensor but I'm having a few problems. There doesn't seem to be much online about using the ICL7107 with a LM35 and most of the schematics available are for volt meters, but that's not a massive problem as the LM35 gives 10mV/C linearly. I'm just trying to go based on the few schematics I have found but I'm wondering about the supporting components for the LM35 which seem a little too simple. The first schematic I found was from a Hungarian electronics forum and seems to depict a diode and amplifier being used for the temperature sensing which seems like a bad idea to me. The second seems more like what I'm trying to do. The other few things are the negative voltage source, the first schematic shows an inverter being used as does the datasheet, but the second schematic shows an LMC7660 voltage converter which seems like a better option to me. The second one does also show three diodes in series used to drop the voltage for the LED displays which doesn't seem like the best idea, but I can't think of a better way to do it without attaching resistors to each one as the number of lit segments will be variable. The supporting components for the ICL7107 seem pretty consistent between the two and the schematic so I'm confident those are correct, but I'm looking for some advice on how to connect the LM35 in a way that will give me an accurate readout. Thanks!

Topic by andy70707 5 years ago  |  last reply 1 year ago


How to make a 5 channel Vu meter (equalizer)

Hey guys, I'm planning on building a sound equalizer display aka Vu Meter, with 10 segment LED. My idea is to make a central sound system with analog I/O for 5.1, with three stereo amps DIY kits, each one for Front (LR), Back (LR) and Sub/Central. I've been using a 2.1 Logitech since my Samsung 5.1 home theater died, and its not enough.  At first, I though about buying a new 5.1 system, but my budget is not enough right now, and as I always loved to build myself, I though, why not? In resume, its a central with volume control, LED to indicate volume output, and 5 rows of 10-segment LED for graphic equalizer. I'll attach an image with the sketch of the frontal look. Its not final, but it may be enough. Now the problem: My knowledge about this sound frequency area is pretty poor. I can't figure out how to make each LED Segment for an specific hertz. I'd like to divide it into 60Hz, 230Hz, 910Hz, 3kHz and 14kHz. For material, I'm planning on using laser cutted MDF for the box and glass for the front panel, to give it a "pro" look. I may change it for acrylic in the end.  The tools I own right now are:  1x Arduino Uno R3, which I intend to use it for the prototype and tests. 1x Arduino Mini, I'd rather use this one instead of an non-writtable CI for final project, as I may want to change codes and add stuff to it later. 5x 10-Segment LED Bar 5x Lm3914 I'd like to get to know how to divide and convert the frequencies of the sound into graphic, tips about the code for arduino and material list and mounting guide for each segment... Thanks a lot, I'm sorry for the long text, but I could not figure out how to explain it in other way. And again, thanks!

Topic by deadlyredink 1 year ago


Can someone please help me create a simple 7-segment number display? [see below for details]

Background info : My name is Simon. I'm a member of the Classic Celica Club of Victoria (Australia) that competes in an anual event called the Winton 6hr Regularity Relay. It's a 6 hour long track event with about 40 teams and 6 cars per team. Each team has one car on the track for the 6 hours. Prior to the race, each car nominates a time that they believe they can consistently do for their share of the race (usually approx. an hour each). Points are awarded for each lap achieved that is within 1 second of the nominated time. Points are deducted for any lap that is faster than the nominated time. The thing is THE DRIVERS CANNOT CARRY ANY FORM OF TIMING DEVICE IN THE CAR. The aim : To build a board that clearly displays a 3 digit time. (eg: 1min 56sec).  Team members will time the car on the track and then use the board to display the time for the driver to read as they pass by the pit wall.  (note: this practice is not against the rules). The requirements : The board must be big enough, and clear enough, to be read from >75m away. The adjustment of the board must be very quick and intuitive. (the task of timing is shared around and there's no time to train people to use the device). The board must be light enough to be held by outstretched arms. No timing device is required in the board itself. The time displayed on the board isn't always the time that is recorded. Adjustments are sometimes made for one reason or another. Scrolling through the numbers is fine, so long as you can scroll both up and down. Each digit should be completely individual (ie: not linked). Layout : [see attached images] I was thinking of using a typical 7-segment display layout made up of 79 x 10mm LEDs. The actual physical construction of the board is well within my ability. It's all the circuitry that i am clueless on.  I am a total newbie so please be gentle when describing electronics. I'm new to instructables but i have spent quite a few hours searching this site for answers. The thing i've found is that my device is far simpler than anything posted on here but i'm still too much of a newb to work out how to do it. ps: I hope i have posted in the correct section. Simon.

Question by Si Mo 9 years ago  |  last reply 9 years ago


My last instructable is not showing up in recent section

Yesterday, I posted a instructable in Technology section under Arduino channel. The public link works, but it is not showing up in recent as well as in search results. Here is the link - https://www.instructables.com/id/DIY-Digital-Clock-With-7-Segment-LED-Display/. Can anyone address this problem and suggest what I did wrong there? This never happened before to me.

Topic by Being Engineers 4 months ago  |  last reply 4 months ago


Seach has failed me. :(

Hey all,I'm new here, but i've made a tonne of things from this site, and always forget to register. ANYWAY, i came across something a few weeks back, and i just cannot find it again. Please please please help me.I think i was looking for something on how to make LED's react to sound or possibly a guitar valve amp or a spectrum analyser, when i came across it. It was some sort of LED or filament bulb or something, that was being built as a decoration. I'll try to be as descriptive as i can here. The actual LED/Light thing wasn't an LED. It looked like a filament bulb, but instead of it just being a light, it made symbols, text etc etc. It wasn't like a segment led or anything led related, it looked more like a filament in it. The lamp itself was box shaped, and it looked like it was about 50mm x 50mm x 50mm. I can't even remember the name of what that lamp display type thing was. There were a few things i've come across that remind me of what that thing was. It was a bit like a display version of one square of one those old school alarm clocks where the numbers flipped down?Sorry if this is a bit vague, i'm hoping it might jog someone's memory?

Topic by trad3mark 9 years ago  |  last reply 9 years ago


diode logic

I'm making a giant adding machine using only resistors(miscellaneous), switches SPST (for input) LEDs (for display) and diodes(for logic). NO TRANSISTORS I have it so that it can recognize 0,1,2,3,4,5,6,7,8,9, but if it recognizes 8, then it recognizes it as all the other numbers. If it recognizes 0, it recognize 1, and 7. If it recognizes 6 it recognizes 1, and 5. If it recognize 9 it also recognize 7. If it recognizes 3, it also recognizes 7. basically if you take a 7 segment display, any number on it, it'll recognize all the numbers in the number. I need help sorting it ou so that if it recognizes 8, it only recognizes 8. If it recognizes 3, it only recognizes 3. Etc...

Topic by guyfrom7up 11 years ago  |  last reply 7 years ago


EL Wire and Paper watch!

Just thought of this! Has anyone ever tried to make a watch/clock using el wire? I thought of making a simple 7 seg led design with a paper (this modeling plasitc) cover/strap as a wrist watch... Get the insides of a 7 seg type led watch. Use electroluminescentwires instead of segments. Put the wires bhind a paper face which is designed as a single piece with strap. attach battery. BINGO! Only thing I've not been able to verify - need to use an el inverter for the display Anyone had any dealsing with this technology and can tell me about it.. meanwhile I'lll scour the instructables Thanks

Question by sParekh 10 years ago  |  last reply 10 years ago


Slot Car Lap Counter using Hall Effect Sensor & Arduino

Hi guys, For a university project I am using a hall effect sensor to count laps of a slot car. I am hoping to count the laps and output the number to a 7 segment LED display. However I am very new to coding and arduinos themselves. I was wondering if anyone had any similar projects or knows of any code I could use or any ideas people may have for a potential solution. Any response would be greatly appreciated. Thanks.

Topic by TomR77 3 years ago  |  last reply 3 years ago


Connect a Sketch Answered

This is a People counter, well hope to be if working.ha. Lazer across a doorway hitting a LDR. The 4 digit 7 seg display counting up 1 each time a person breaks the beam.  As of now i  have a counting sketch from the Sparkfun example. It is counting up 0 to 999 and at the same time i have an LDR reading to the serial monitor and blinking the LED on pin 13. But they are not "interacting". I am trying to get the beam breakes from the LDR to advance the count by 1 every time it is broken. In the loop function is the mills that was advancing the counting. I have changed it to   displayNumber(counter).  Among other things.But i haven't been successful in having the LDR advance the count. The sketch is still missing some "stuff". What could i change to have the counter advance by 1 every time the lazer beam is broken?    Thanks W /* 6-13-2011 Spark Fun Electronics 2011 Nathan Seidle This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license). 4 digit 7 segment display: http://www.sparkfun.com/products/9483 Datasheet: http://www.sparkfun.com/datasheets/Components/LED/7-Segment/YSD-439AR6B-35.pdf This is an example of how to drive a 7 segment LED display from an ATmega without the use of current limiting resistors. This technique is very common but requires some knowledge of electronics - you do run the risk of dumping too much current through the segments and burning out parts of the display. If you use the stock code you should be ok, but be careful editing the brightness values. This code should work with all colors (red, blue, yellow, green) but the brightness will vary from one color to the next because the forward voltage drop of each color is different. This code was written and calibrated for the red color. This code will work with most Arduinos but you may want to re-route some of the pins. 7 segments 4 digits 1 colon = 12 pins required for full control */ #define ldrPin A2    // pin used for input (analog)    int digit1 = 11; //PWM Display pin 1 int digit2 = 10; //PWM Display pin 2 int digit3 = 9; //PWM Display pin 6 int digit4 = 6; //PWM Display pin 8 //Pin mapping from Arduino to the ATmega DIP28 if you need it //http://www.arduino.cc/en/Hacking/PinMapping //int ldrPin = A2; int segA = A1; //Display pin 14 int segB = 3; //Display pin 16 int segC = 4; //Display pin 13 int segD = 5; //Display pin 3 int segE = A0; //Display pin 5 int segF = 7; //Display pin 11 int segG = 8; //Display pin 15 int ldr_pinValue; int counter; int currState; int then; //int ldrpread; //int digit[4]; //int leftover; int LDR = A2;                                //analog pin to which LDR is connected, here we set it to 0 so it means A0 int LDRValue = 0;                    //that’s a variable to store LDR values int light_sensitivity = 500;  //This is the approx value of light surrounding your LDR //int digit_to_show = 0; int ldr_Pin = 0;  // LED status (0 = low, 1 = high) int inVal = 0;    // variable used to store state of input int switchOn = 725;   // value at which we switch LED on int switchOff = 550;  // value at which we switch LED off void setup() {         {     Serial.begin(9600);            //start the serial monitor with 9600 buad     pinMode(13, OUTPUT);     //we mostly use13 because there is already a built in yellow LED in arduino which shows output when 13 pin is enabled   }       pinMode(ldr_Pin, INPUT );    pinMode(segA, OUTPUT);   pinMode(segB, OUTPUT);   pinMode(segC, OUTPUT);   pinMode(segD, OUTPUT);   pinMode(segE, OUTPUT);   pinMode(segF, OUTPUT);   pinMode(segG, OUTPUT);   pinMode(digit1, OUTPUT);   pinMode(digit2, OUTPUT);   pinMode(digit3, OUTPUT);   pinMode(digit4, OUTPUT);     pinMode(13, OUTPUT); } void loop(){ {     LDRValue = analogRead(LDR);          //reads the ldr’s value through LDR which we have set to Analog input 0 “A0″     Serial.println(LDRValue);                  //prints the LDR values to serial monitor     delay(5);                                                //This is the speed by which LDR sends value to arduino     if (LDRValue < light_sensitivity)       {         digitalWrite(13, HIGH);       }     else       {         digitalWrite(13, LOW); {    if (currState() >  300) then         currState = HIGH    } else     currState = LOW //endif if currState != prevState and currState == LOW then // LOW or HIGH depending on the circuit     counter++     prevState = currState endif      //long startTime = millis();   displayNumber(counter);     //while( (millis() - startTime) < 2000) {   //displayNumber(1217);   //}   //delay(1000);    } //Given a number, we display 10:22 //After running through the 4 numbers, the display is left turned off //Display brightness //Each digit is on for a certain amount of microseconds //Then it is off until we have reached a total of 20ms for the function call //Let's assume each digit is on for 1000us //Each digit is on for 1ms, there are 4 digits, so the display is off for 16ms. //That's a ratio of 1ms to 16ms or 6.25% on time (PWM). //Let's define a variable called brightness that varies from: //5000 blindingly bright (15.7mA current draw per digit) //2000 shockingly bright (11.4mA current draw per digit) //1000 pretty bright (5.9mA) //500 normal (3mA) //200 dim but readable (1.4mA) //50 dim but readable (0.56mA) //5 dim but readable (0.31mA) //1 dim but readable in dark (0.28mA) void displayNumber(int toDisplay) { #define DISPLAY_BRIGHTNESS  500 #define DIGIT_ON  HIGH #define DIGIT_OFF  LOW   long beginTime = millis();   for(int digit = 4 ; digit > 0 ; digit--) {     //Turn on a digit for a short amount of time     switch(digit) {     case 1:       digitalWrite(digit1, DIGIT_ON);       break;     case 2:       digitalWrite(digit2, DIGIT_ON);       break;     case 3:       digitalWrite(digit3, DIGIT_ON);       break;     case 4:       digitalWrite(digit4, DIGIT_ON);       break;     }     //Turn on the right segments for this digit     lightNumber(toDisplay % 10);     toDisplay /= 10;     delayMicroseconds(DISPLAY_BRIGHTNESS);     //Display digit for fraction of a second (1us to 5000us, 500 is pretty good)     //Turn off all segments     lightNumber(10);     //Turn off all digits     digitalWrite(digit1, DIGIT_OFF);     digitalWrite(digit2, DIGIT_OFF);     digitalWrite(digit3, DIGIT_OFF);     digitalWrite(digit4, DIGIT_OFF);   }   while( (millis() - beginTime) < 10) ;   //Wait for 20ms to pass before we paint the display again } //Given a number, turns on those segments //If number == 10, then turn off number void lightNumber(int numberToDisplay) { #define SEGMENT_ON  LOW #define SEGMENT_OFF HIGH   switch (numberToDisplay){   case 0:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_ON);     digitalWrite(segF, SEGMENT_ON);     digitalWrite(segG, SEGMENT_OFF);     break;   case 1:     digitalWrite(segA, SEGMENT_OFF);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_OFF);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_OFF);     digitalWrite(segG, SEGMENT_OFF);     break;   case 2:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_OFF);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_ON);     digitalWrite(segF, SEGMENT_OFF);     digitalWrite(segG, SEGMENT_ON);     break;   case 3:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_OFF);     digitalWrite(segG, SEGMENT_ON);     break;   case 4:     digitalWrite(segA, SEGMENT_OFF);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_OFF);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_ON);     digitalWrite(segG, SEGMENT_ON);     break;   case 5:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_OFF);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_ON);     digitalWrite(segG, SEGMENT_ON);     break;   case 6:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_OFF);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_ON);     digitalWrite(segF, SEGMENT_ON);     digitalWrite(segG, SEGMENT_ON);     break;   case 7:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_OFF);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_OFF);     digitalWrite(segG, SEGMENT_OFF);     break;   case 8:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_ON);     digitalWrite(segF, SEGMENT_ON);     digitalWrite(segG, SEGMENT_ON);     break;   case 9:     digitalWrite(segA, SEGMENT_ON);     digitalWrite(segB, SEGMENT_ON);     digitalWrite(segC, SEGMENT_ON);     digitalWrite(segD, SEGMENT_ON);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_ON);     digitalWrite(segG, SEGMENT_ON);     break;   case 10:     digitalWrite(segA, SEGMENT_OFF);     digitalWrite(segB, SEGMENT_OFF);     digitalWrite(segC, SEGMENT_OFF);     digitalWrite(segD, SEGMENT_OFF);     digitalWrite(segE, SEGMENT_OFF);     digitalWrite(segF, SEGMENT_OFF);     digitalWrite(segG, SEGMENT_OFF);     break;   } }

Question by WWC 6 years ago  |  last reply 6 years ago


I2C to SPI BASIC code conversion?

 Hello all. Pretty daft and most likely simple sollution to those who know what they are doing I'm sure. I am building a 132 LED clock (60 for seconds, 60 for minutes and 12 for hours). I'm using a Picaxe 28X2 and will most likely be using 3 MAX7221's to display the LED's, 1 each for the hours, minutes and seconds. I'm currentlty using a DS1307 RTC module to keep time. Exposition over!  My question is, I am using open source code from a guy who made a clock using Pic 28X1, MAX7221 and DS1305 displaying on four 7-segment displays. now the differences between the Pic's with regard to coding I can handle, although I do have a 28X1. The fact that the DS1305 and 1307 use SPI and I2C respectively means that the differences between comms protocols are confusing the hell out of me.  Now please forgive the length of this question. Basically, I need some pointers as to whether it would be better to try and convert the code to use I2C for the RTC and stick with SPI for the MAX or should I just buy a DS1305 at almost £6 per chip and make my life a bit easier? I have already tried using the code with my 1307 but the 7-seg display I have just stays on the No2.  As for the differences in display type...well I'll come to that once I get the timing working.  If I've left anything out or you need more information then please let me know.  Here is the link to the clock schematic: http://tech-tut.com/wp-content/uploads/2008/08/real_time_clock_advanced_schematic.pdf    And the code is far too long to be pasted here I'm affraid and the file I originally got it from had converted it into word which pushed all the lines together. That was a fun few hours sorting that out! Thanks in advance

Question by LED Maestro 5 years ago  |  last reply 5 years ago


YY:DDD:HH:MM:SS Countup Clock

I was looking to make a countup clock that would be able to count off time in seconds, minutes, hours, days, and years using seven segment displays. I have yet to be able to find an instructable like this. I imagine it would be very similar to a normal clock; however I do not know enough about electronics to be able to modify the standard clock instructables to be able to make my own.  The only way I know to do this with the knowledge I currently have is to make a mini PC and that would be cost prohibitive as well as overpowered.   The idea came up because I have my one year anniversary approaching and I figured it would be neat to have a clock whose sole purpose is to give an exact time count of being married.  I played around with the idea of having the clock play a song or display something any time a new year was added, but I figured for now to just stick to the basics.   If anyone knows of an instructable that fits this idea or is willing to make one/point me in the right direction here, that would be fantastic. 

Topic by NELHAOTEC 3 years ago  |  last reply 3 years ago


Creating a minimal LED clock with Arduino for those with poor eyesight?

I've always had poor vision and cannot see any clocks at night without glasses or contact lenses.  Analog clocks are of no use.  7-segment clocks would have to be so big and bright, that they'd keep everyone up at night.  Clocks that make noise would create similar problems. I have an idea for a clock that has four, rather dim LEDs flashing the time constantly.  I need a LED for each place value: 10hr, 1hr, 10min, and a 1min LED, in different colors as necessary.  I could also settle with a 5hr, 1hr, and 5min LED setup.  As the clock runs, each place value would be blinked, pause a few seconds, and repeat the process.  That way, just a quick count would let me know how much sleep time I have left. Since I'm new to Arduino, it's beyond me for now.  I'm looking for pointers as I haven't found any clock projects with such a simple display. Has anyone seen any code snippets that could help me out? What would be a good timer (GPS, WWVB, RTC, etc.)? Where would be a good place to start? I'm not looking for a finished product, obviously.  I want to write the code myself.  But I also would like some good building blocks to begin with to help me learn the process. Any help would be appreciated!

Question by beartard 8 years ago  |  last reply 8 years ago