Search Engine

Led And Blinking

Add Question

1000 Threads found on Led And Blinking
lvd connected to VDD : diode and cap But please help me understand how use this if I use 7-segments led with common catode(-). How use separate VDD for led and PIC with diode and cap?
This combination, led+LDR, may be difficult to find, so here is the recipe for building one by yourself: Regards, IanP
im trying to build a rpm meter using infrared led and phototransistors.i need help with the ciruit and its interfacing with atmega 16 and also an idea how to write the code,thx in advance
Every logic family is characterized by different output drive current .. For example, 74ACT logic family can drive +/- 24mA of IOH and IOL .. Any output current above ≈5mA can directly drive an led (via a resistor) .. You have to google for I of your latch .. Rgds, IanP :D
I wrote a program counter for led and 7 a time both has to run.but 7 segment started run after that led started. here c1,c2 as a switch. This is my program #include unsigned int t,i; #define p0 P0 #define p3 P3 #define p1 P1 sbit c1=p3^2; sbit c2=p3^3; void led(); void segment(); void wait (int (...)
Hi please help !! ....I made a clap switch with an led and it worked fine clap switch as it is shown in the image attached is a clap On only switch and the led goes off fading within a certain time , then I clap again to ligh it on . Now I just wanted to change the led with a DC Fan ...everything went fine (...)
Two possibilities come to mind: 1) Solder wires to existing led connections and have them connect to a buffer amplifier with high input impedance, to drive external led. 2) Mount a CdS photocell next to each led, in a light-tight enclosure, and use the resistance change to trigger the external (...)
there is two possible defects in your circuit. However, if the led blinks for about 10 times your tuner is defective 90%. To be sure if it is a tuner or an IF circuit. Isolate the tuner first then the IF circuit. you can check this using a scope. Thanks. I Hope this helps:D
I test MULTISIM circuit make blinking led with PIC 16f84. Assembler code is ok and working good but if i attach one led with resitor over port RB0 pic pic16f84 this led dont blink becouse the level in OUT over port go to 0. Is same led and resitor make short circuit over (...)
Hi all, I have a project, below is the requirement: -> Control led brightness + blinking rate(OnTime and OFFtime). I am able to control the led brightness using PWM. My idea is using Timer to set the blinking. How can I compile the PWM and TIMER together? Microcontroller: (...)
Hi all!! I tried to blink a led and I can't as expected. I use CCS C. The hex file is working with ISIS properly. The code and the circuit are attached below. Can anybody tell me the mistakes?? Thanks in advance... #include <16F877A.H> #use delay (clock = 20000000) void main(void) { while (1) { output_high(PIN_A0); delay_ms(
Hi, Take a look at the comparator and ADC sections in the datasheet and how to disable them. The difference between 16F877 and 16F877A is the presence of an analog comparator in 16F877A and this needs to be disabled if the related pins are to be used as digital IO. ADCON1 = 7; //ADC off CMCON = 7; (...)
The simplest way is to buy a flashing red led and connect two more plain red leds in series to it
why the led keep blinking even thought i not press any button. pls anybody correct the code for me. thank you unsigned short i; void main() { TRISB= 0xFF; PORTB=0x00; TRISD = 0x00; // PORTB as ouput PORTD = 0x00; // Set port output as all 0's while(1){ if(TRISB.F0==1) { // Detect logical one to zero for(i=0;i <50; i++){ //re
Hi there i try to build an error code monitor with 1 led..i need like 10 input when input 1 is selected led is blinking 1 time after 3 seconds off blinking again... when input #2 is selected led is blinking 2 times 3 seconds off and blinking again....number (...)
Dear masters, Please help me. I have NEC Laptop, model Versa P8100 with Intel Pentium Mobile Celero 1,7Ghz, 2Gb of ram. have trouble the LCD screen is Blank... even Back lgiht not light. and, the power led and charging led was blinking... Fan for cooling system rotate in high rpm. i've browse for (...)
Hi everyone, I have an assignment to do i.e, 8 leds blinking one after the other on Spartan 3E board. The pattern for leds should be started from right most led and continue to the left one. after one round completion it should again be started from right. I know the basics to divide clock, the question (...)
you want to have leds blinking ? at which frequency ?
Dear all: anyone have the paper and block diagram of ldo, led,audio speaker and temperature sensor, i really need them, thanks!!!!!!!!! my msn:
Hi, For 1), you can use two 555. The first one as a monostable and the second one as an astable. The astable period be the blinking period of the led diode. The monostable period should be 5 second. The monostable output (3) should be connected to the reset pin (4) of the astable.
Just at first glance: You have a while(1) loop in the main program where you start the conversion by giving a pulse on ADC0804 /WR line via P3.0 at periodic 50 ms. At the end of each conversion EOT, INTR goes low and a service interrupt is performed. Though the HY62256 it's mapped only up to 7FFF, you count up to 0xFFFF. Let's say it's harmles
The led IS blinking but the time that remains in the off state takes about 2 or 3 instructions time, and the on state takes what the generic delay says. you should use a simulator so you can find bugs like this one easily. regards.
Would you care to do this tests also?: Test it with one led. Simulate the whole thing with MPSIM (replace the delays, if any, by single lines). Is it possible to format your code to post here? I don't feel akin to read such a mess.
I have this program which i want to modify to control led and reset the PIC via USART and VB6. i added some modifcation to allow led on when it receive any data from USART. The code display text to an LCD. simulated this in proteus and i used virtual serial port driver. I need help to detect (...)
Is it possible to make a distance measuring sensor using IC 555 and IC 565 along with an IR led and photodiode pair? I have the transmitter circuit which pulses the IR led at a particular frequency using IC 555(used in astable mode). Now I want to design the receiver circuit using photodiode and IC 565(PLL) (...)
hi, i need some design on to drive luxeon led and control the brightness of is better if the design is a swichmode type current source so i can vary the current and change the brightness of the led. please post your suggestion about this! Thanks a lot! rgds dilan
dear friends can we connet the ir led to the tx of one mcu and ir receiver to the rx of other mcu and do the communication? will it work perfectly or is there any possibility of data loss? ml
How to connect an led to a 8085 Microprocessor and toggle it.
Hi Mr. Karan, I went through your post & corresponding replies. In your schematic You have not mentioned led positioning, connect led with Series resistor of 1K on RA0 then try.
may be the connections are loose so when you are touching the terminal it glows its because of the dry soldering or another problem may be you are not using a pull up resistance for the led to give it a proper supply
Hello Friends, I read all ur discussion. i am new in digital circuits. I have knowlage of digital circuits and have some programming knowlage too but don't dont' have real world experiance. I have a working led matrix matrix of 7 rows and 96 rows. I want to test it with my won microcontroller. I am going to use this with my
I intend to use BC557 (PNP) transistor in indicator circuit, +at pin 1 (E), connect a + pin of led at pin3(C), and the -pin of led to Ground, the led is not glowing (6V input), when positive volt is given through pin2 (B) the led is glowing, since the transistor is PNP type if the base is biased the (...)
there is no differance electricaly all diodes will light up if you reverse bias them its just what band they emit on and led's are built to emit on specific wavelengh using techniques like tunnel or layer etc... best you study led's datasheets and info ... rather than ask daft questions (...)
I am creating a firmware for PIC18F4550 with the function of BlinkUSBStatus inside. But when i toggle one of my other leds from on to off or vice versa, the blinking led stops blinking. I am wondering why it will stops blinking. Actually the purpose of the blinking led is (...)
Circuit to count led pulses and latch on right number Should be quite simple.... I think...? Say cct 'sees' 24 blinks - then no more (ie, too many means no_good) I'd prefer it f this can be done without a microcontroller - ie. a simple fixed cct (no need to be able change the correct count once built). If the right number - then latch is Se
hi, any body can help me to know what is max input voltage can give to normal led, as well as for power led?
white is the transmitter and black is the receiver.... you can do a simple test to know the transmitter and receiver with your mobile phone with camera.... power ON the led. and thrrough the camera look at the IR led... the transmitter will emit light which cannot be seen through naked eye... you (...)
What are the minimum voltage and current values required for glowing a red led? I seen that 1.7v is the nominal voltage,what is meant by nominal in that case?
I have a proximity sensor setup which I'm trying to fix. It was removed from a Hand Dryer. It consists of an IR led and IR Decoder which are side by side and separated by a plastic housing. When your hand comes close the IR led light gets reflected back into the IR Decoder. I (...)
Measuring RPM would mean simply measuring the period between pulses from your photodiode, then some clever maths (once you know how many pulses per rotation, and your CPU's osc frequency) to convert this revolutions-per-minute. However, in order to measure direction, you'll need a second led/photodiode pair, perhaps with its own set of hole
Vusb should have a 0.47uF ceramic capacitor connected, with the other side of the capacitor going to Vss. I seem to remember that the capacitor needs to be there even if you are not using USB. Actually, that is not the case, if you do not indeed on implementing the USB interface, you can run the PIC18F2550 fin
Hi every body I want to write codes in this way that with a micro switch, I turn led ON/OFF. but in this way that when for the first time I press micro switch the led should be turn on and right after I pick up my hand from micro switch, timer start calculating 1 sec, and if before 1 sec I press the (...)
Main task of the system is to detect presence of people in a room by lighting up led strips which illuminate the ceiling (7 meters of white strip 2700K). Clicking the switch enables additional lighting in the form of
Beam break detector! you can use an IR detector module using a photodiode on one side and an IR led on the other. When someone enters the room then the IR signal being received by the photodiode will be interrupted and this activity can be monitored though a microcontroller.
hi which type of lcd you are referring with? graphical/charector/segment? single led/led array/7 segment? all are different ml
Hi, Im trying to get a PIC18F458 dev board to say something, anything! I started first with a VFD and now have scaled back to a simple led program. Have 2 source codes. Can someone point out where the encoding is at fault and what it should be? Appreciate. led: //05-03-12 led TOGGLE (...)
Dear Sir / Madam, Can you please suggest any low forward current led which can give good mcd? I am using this led in a PCB as an indicator. How much mcd is good enough for an indicator led? How to visualize or quantify mcd of an led? Thank you very much in advance, Regards, Madhusudhan
Hi there, I am having a SIM908 EVM board. I was able to send AT Commands and receive GPS data from a hyper terminal and a PIC24F. My next step is to send the GPS data to a backend server over a HTTP POST. I inserted a sim card in the EVM Board. I am using a normal power supply provided in the EVM kit. The VBAT led is (...)
Hi all, I am looking for a cheap, single color, near IR led/Laser Diode and a receiver photodiode for it, with a center wavelength of about 1550 - 1600 nm to monitor blood glucose this one: led1450E or this one:
Hi, can someone help me create a component in ISIS and ARES? Inside ISIS only has 2 pin bi-color led and i have failed to create a 3 pin bi-color led. Below is the link to the component's data sheet.