255 Threads found on edaboard.com: Led Example
I agree with d123.
* Fuctionally you may use the 4067.
* There are dedicated relay driver ICs. They may be controlled with SPI or I2C
* you may use some logic IC like HC138 combined with a led driver like ULNxxxx
There are many, many example circuits here in this forum and even more in the internet.
Hobby Circuits and Small Projects Problems :: 03-23-2017 06:59 :: KlausST :: Replies: 4 :: Views: 500
I want power my led using I-Phone lightening connector.
Have anyone tried to do that or Did you have any suggestion for me?
For example:- Powering a USB fan. Instead of USB ,I want to use I-Phone to power on my led.
Power Electronics :: 12-17-2016 14:17 :: Manivannan M :: Replies: 0 :: Views: 360
A vague description...leads to vague answers..
I assume with "current limiter" you mean someting like a inrush current limiter for transformers.
If this is the case, then it is completely unsuitable for leds.
Please give more details or example circuits, links to datasheets, web pages, discussions, or device names.
Power Electronics :: 07-02-2016 09:11 :: KlausST :: Replies: 2 :: Views: 321
As soon you will show your code and schematics, as far you will get any usefull help.
i've tried learning C from example9 :two digit led counter
but its not working even after correction of MikroE team
here is the schematic
Microcontrollers :: 04-21-2016 07:48 :: janosandi :: Replies: 15 :: Views: 1057
After using mTouch framework, I am trying my hand on dedicated CPS channels (CPS0-CPS16). I have written the code for same which looks running except some pitfalls as follows.
When I press input X (for example), led for (X+1) glows. I see, everytime i call ISR kaflg value is written at kflag. please help me to
Microcontrollers :: 04-11-2016 16:04 :: pravin b :: Replies: 3 :: Views: 739
I have an led board where i want to add a circuit to control the brightness,
input parameter of the led board DC voltage ( 12V, 350mA),
i want to add a circuit in such a way that when the voltage turns from 12V to 0V and again 12V ( low pulse of few ms) the current decrease ( for example from 350mA to 200mA),
and when again i do (...)
Elementary Electronic Questions :: 04-08-2016 08:12 :: yassin.kraouch :: Replies: 6 :: Views: 719
My name is Ashley, I live in the UK, I work with alarm systems but have not worked at a component level for quite sometime.
I have a variety of bit at my disposal and have retro fitted my gun cabinet with a 12vdc led strip light.
The Magnetic contacts I use in work are what we call normally closed for example when a door is in its closed pos
Hobby Circuits and Small Projects Problems :: 03-08-2016 09:20 :: daiashthomas :: Replies: 0 :: Views: 2
I need to rotate for an example x=0XFF for 3 to right.
I cant do that only with >> because that is shifting.
When you want rotate you need to "memory" all bit not to lose such as in case for shifting (i think).
So that is not the same.
May I use this
display= (x & 0xFF)>>3 ; // display is diodes which simulating bits...
Microcontrollers :: 02-09-2016 15:06 :: 8051HELP :: Replies: 0 :: Views: 16
I have never played with the Sitara boards, but an SPI screen is really easy to use.
If you find a way to use GPIO (try to blink a led for example) and a SPI, then you just
wire the SPI to the LCD, the GPIOs to the proper places (usually chip select, Data/Command,
Reset) and you're on the right way.
Usually you can find the initialization p
Microcontrollers :: 12-25-2015 12:00 :: doraemon :: Replies: 1 :: Views: 892
Can you separate the loops for scanning the matrix display and for moving the characters.
For example, you can create a loop that writes to the entire matrix every mSec (say) but only shift the characters every 100 times ( of whatever) through that loop.
I assume that the brightness form the matrix is a direct function of how long you keep the led
Microcontrollers :: 11-23-2015 01:47 :: Aussie Susan :: Replies: 2 :: Views: 701
There must be 50,000 led driver designs in production by now.
If you are referring to a long string of leds with a buck CC regulator from a HV source, then a HV process is used.
But not for a LV solution
For example this part has a range of 2.5 to 6V and can supply leds up to 3A. for only $0.95 with 470nH choke total BOM (...)
Power Electronics :: 11-11-2015 21:26 :: SunnySkyguy :: Replies: 3 :: Views: 659
If the displays are only 7 segment you only need 7, PORTD pins for the segments and another PORT's 4 pins for digit select.
This will leave PORTD.0 free for the serial RXD.
ULN drivers were used as they were very large led's
Microcontrollers :: 09-26-2015 11:40 :: esp1 :: Replies: 11 :: Views: 936
Besides the low current capacity mentioned above, you need to be aware that using some led with color other than red, this effect is even more noticeable because the voltage drop will be greater in other colors. What you can do is to use a transistorized external circuit to amplify this current, like the ULN2003 IC for example.
Microcontrollers :: 08-18-2015 11:16 :: andre_teprom :: Replies: 33 :: Views: 1665
I'm using the LT3797 led driver in a SEPIC configuration. It uses a high-side currents sense resistor to set the output current. I'm following this circuit example for my application.120053
I would like to be able to "scale" the sense resistor on-demand (from a microc
Analog Circuit Design :: 08-12-2015 15:33 :: jstamour802 :: Replies: 4 :: Views: 765
I'm new to this, but I need help writing a code (MPLAB in C) for a frequency counter with a 4x 7 segment display using a PIC18f252, and a 74HC4511 driving the display.
it needs to work in the range 15hz to 200hz.
Thanks so much if any one can help ;)
Microcontrollers :: 07-14-2015 12:02 :: Kerryannewood :: Replies: 3 :: Views: 532
For a state machine, you have to list up the possible states (and combinations of states), and
list up the inputs / events that cause changes from a state to another. Here is an example (not
in C, in pseudo code with a C syntax).
Let's say you want to toggle a led with a button press. You have 2 states, led_ON and (...)
Microcontrollers :: 06-20-2015 01:34 :: doraemon :: Replies: 3 :: Views: 509
THis is a good example of a cheap design that costs about 50 cents to make in CHina. What did you pay?
REMOVE all 100 Ohm resistors for 27 V use. I assume you didn't get instructions.
THe middle Resistor is beyond rated power with taillight on only 380mW so will rather hot to touch and should use two 1K resistors or so in parallel for cooler oper
Hobby Circuits and Small Projects Problems :: 06-17-2015 09:05 :: SunnySkyguy :: Replies: 12 :: Views: 953
Texas Instruments datasheets for CD4xxx ICs show detailed graphs of minimum and typical output current sink and source at 3 supply voltages. The graphs allow you to select a load voltage drop (I use an led forward voltage). For example with a 10V supply the typical shorted output source current is 20mA or 18mA into a white 3V (...)
Analog Circuit Design :: 05-22-2015 01:52 :: Audioguru :: Replies: 2 :: Views: 427
I have recently discovered that a 4kV ESD event was causing my board to fail due to a discharge on the RJ45 shield, which then traveled to the led and into the IC causing it to fail.
What is a good way to protect that IC for FCC cert, and is there a good doc/example out there? I did put protection on the datalines, but didn't think of (...)
Professional Hardware and Electronics Design :: 05-07-2015 21:00 :: jelydonut :: Replies: 2 :: Views: 1217
Not sure which sensor you are actually using, 02BZ2.2 is a zener diode. Presumed it's any kind of photodiode (or a led used as photo diode), you can expect better results when operating the diode in zero voltage bias than in photo element mode. See the below circuit as an
Elementary Electronic Questions :: 05-03-2015 10:01 :: FvM :: Replies: 7 :: Views: 710
1. If your PIC is not going to do anything else besides beeing this PID... I suggest you to use a Timer flag to synchronize the ADC readings... for that, you need some idea of how much time it takes to process all this program... (for example, add a togglin led, and check with a oscilloscope the minimum and maximum time it takes to perform the proc
Microcontrollers :: 03-12-2015 02:22 :: Kurenai_ryu :: Replies: 1 :: Views: 764
How High can you do hand waving descriptions :roll: without a requirement or a comparison is one example of an 6x3 array of XL Cree ledS on ALum-clad PCB powered by one of my surplus wall transformers 20
RF, Microwave, Antennas and Optics :: 01-27-2015 01:29 :: SunnySkyguy :: Replies: 1 :: Views: 553
How good are you with Verilog? Have you tested any simple code like led blinking or 7 segment display? Altera website has many example code which you can take a look at. All the best! :)
PLD, SPLD, GAL, CPLD, FPGA Design :: 01-21-2015 15:33 :: d3javu :: Replies: 1 :: Views: 553
Give me IAR EW ARM example for LPC2148 led blinking.
Microcontrollers :: 01-05-2015 17:54 :: milan.rajik :: Replies: 6 :: Views: 827
Hello, I try to complie (using atmel studio 6 ) example
C code for led
#define F_CPU 1000000UL
DDRB |= _BV(DDB0);
PORTB ^= _BV(PB0);
I get atmel studio error: Error 1 'DDB0' undeclared (first u
Microcontrollers :: 11-23-2014 11:20 :: bigdogguru :: Replies: 6 :: Views: 3487
i have found a video for led matrix, but i d nt now what is the code used.
if any one can help me to give me an idea.
thank you very much.
Microcontrollers :: 11-01-2014 10:26 :: merzouk :: Replies: 2 :: Views: 660
Need an example code for 8X8 Dot Matrix led display in microC.
Basically I was trying to make one. I tried in many ways but it doesn't work. I don't know what was wrong I was doing....
here is my file:
const unsigned short letters =
0xFF, 0x00, 0x76, 0x76, 0x76,
Microcontrollers :: 09-24-2014 08:28 :: Mithun_K_Das :: Replies: 0 :: Views: 1568
i am in need of help for this project that i am doing, i did this schematic that is suppose to work as a 3 way led lamp circuit. (for example, first push on ob switch turns on 1 led, 2nd push is 2 leds, 3rd is all leds and 4th will turn off all the leds). Unfortunately, my circuit is not (...)
Show your DIY :: 05-23-2014 13:23 :: txrxno :: Replies: 0 :: Views: 1158
I am using my own hardware which is built with LPC2368 controller and DP83848 physical layer IC for Ethernet. All the connections are according to the mcb2300 schematic diagram.
and using easyweb example code copied from "C:\Keil\ARM\Boards\Keil\MCB2300" but same code working fine with Evaluation board
the two leds (...)
Microcontrollers :: 05-19-2014 06:54 :: padmaneela :: Replies: 1 :: Views: 788
Hi, thanks for starting this thread.
Many concepts are connected in this topic.
Some concepts seem paradoxical. Not easy to get an intuitive grasp on.
example, we can make a square wave easily, without needing to know anything about generating sine waves. We just switch a DC source on and off.
It might have led me to claim, therefore, that a sq
Miscellaneous Engineering :: 05-18-2014 22:11 :: BradtheRad :: Replies: 4 :: Views: 1280
I am new to pic32 bit microcontroller. I am learning the basic codes like led,LCD,PWM etc.
I found that there is no simulator for pic32 bit microcontroller. For example proteus for 8 bit controllers.
If there is any simulator for pic32 bit microcontrollers?
If there is no simulator for pic32 then
Microcontrollers :: 05-08-2014 16:45 :: horace1 :: Replies: 2 :: Views: 1117
i made a circuit for my led lamp. pub. in Elektor Electronics 9/2003 A simple switched regulator with 70 % efficiency. change R6 and L1 wire size for more current.
Analog Circuit Design :: 04-27-2014 15:21 :: tanveerriaz :: Replies: 9 :: Views: 1752
Please help me, need 16x16 led matrix code................
Microcontrollers :: 04-14-2014 18:16 :: tajulislam805 :: Replies: 2 :: Views: 1644
l I have micro controller 89c51 ,led,switch,compiler(keil),programmer (flesh magic)
SWITCH is input device connected port pin P0.1
led is output device connected port pin P1.1
I have written assembly code in keil software for exampleORG OH
SETB P1.1 ; led IS ON
CLRB P1.1 ; led IS OFF (...)
Microcontrollers :: 03-22-2014 09:05 :: vead :: Replies: 4 :: Views: 557
If you use IR you need a light emitter (IR led for example) which will draw power all the time and quickly drain a battery. The magnet and reed switch suffer the problem that they have to be in very close proximity and if you go fast, the magnet may pass the reed too quickly for it to operate. A magnet and Hall effect sensor will work or another me
Robotics and Automation Forum :: 03-08-2014 11:22 :: betwixt :: Replies: 6 :: Views: 977
i hv started working with pic.
i am using pic 16f676 controllers...
with mplab and pickit2...
can u help me i want some examples for learning. starting from led blink.
also mplab programming in C language or Assembly ...
thanks in advance,
Elementary Electronic Questions :: 03-03-2014 18:34 :: Far Han :: Replies: 0 :: Views: 1356
I think what Mohamed Saa is asking for is a utility to convert an image rather than font characters. For example something that converts a JPG or PNG image into the flash sequence for a rotating led display. As far as I know there are no programs available to do this, it is a rather specialized thing and probably needs coding for each different PO
Microcontrollers :: 02-27-2014 09:25 :: betwixt :: Replies: 5 :: Views: 622
Which ARM MCU you are using
This links is showing STM32F407VG reference of Discovery board which is excellent development board and is example written by me using above development board to blink led
Microcontrollers :: 02-08-2014 06:53 :: PA3040 :: Replies: 2 :: Views: 825
try google using "arm blinking led"
Microcontrollers :: 01-30-2014 06:10 :: kam1787 :: Replies: 1 :: Views: 3065
i am troubling bcoz of USB communication from long time.I have downloaded USB_HID example from keil website.
so how to add this code to my project.Consider it is based on interrupt transfer method.And there is key's on
software and i have to blink led with this aplication.
And if i mark Use memory layout from target Dialog then it gives scatte
Microcontrollers :: 01-29-2014 07:45 :: embpic :: Replies: 1 :: Views: 545
Could you give me please a "Hello World" example?
For instance, if I press the button from Tx board, the led from Rx board turns on.
Microcontrollers :: 01-21-2014 06:05 :: mariuszoll :: Replies: 7 :: Views: 738
Use a microprocessor board with an RS485 port and an led display?
Robotics and Automation Forum :: 11-19-2013 17:36 :: barry :: Replies: 4 :: Views: 1251
Forget the 555 it is completely useless for voltage monitoring.
It is easier to make the led light up when the voltage is high enough and go out as the voltage drops but even then it's quite easy. Before explaining, you need to set some parameters. For example, it's no good saying the led should light up when a 9V battery drops below 9V (...)
RF, Microwave, Antennas and Optics :: 11-16-2013 11:57 :: betwixt :: Replies: 14 :: Views: 5776
I am using 8051 development board with 89v51rd2.When i upload a code the board is working properly.but after a reset the code is not working.i first uploaded a running led code.its working properly.but after a controller reset the led just change.can anyone explain me what may be the cause?
Microcontrollers :: 11-09-2013 06:21 :: jovin555 :: Replies: 3 :: Views: 660
unsigned char x;
// Interrupt Handler
// RB Port Change Interrupt
if(PIR1.RBIF == 1) // if the RB Port Change Interrupt flag is set...
PORTA.F1 = ~PORTA.F1;//led on/off on press of switch
x = PORTB; // Need to read or write to the port to clear mismatch condition
Microcontrollers :: 11-07-2013 16:26 :: asking :: Replies: 3 :: Views: 499
The base-emitter voltage is a range of voltages so the actual amount of current in the current sink is a wide range.
The transistors probably do not match (but it is better since they are thermally joined) so the currents probably will not match as well as the example.
The base currents are on the left side so I think the led current is hig
Elementary Electronic Questions :: 10-25-2013 23:23 :: Audioguru :: Replies: 3 :: Views: 631
This is another example. There is in Keil\C51\examples\BLINKY
/* BLINKY.C - led Flasher for the Keil MCBx51 Evaluation Board with 80C51 device*/
#include // changed
// When you have enabled the option Stop Program Execution with Serial
// Interrupt, the Monitor-51 uses the serial interrupt of (...)
Microcontrollers :: 10-26-2013 10:42 :: nagkiller :: Replies: 6 :: Views: 616
first, maybe is better for you to test your sensor alone with out mcu,
use for example 9V battery, connect + and -, on the back side of sensor you probably have led indicator, when metal is close to sensor, led will light,
check your black wire and condition when led light,
Microcontrollers :: 10-21-2013 07:42 :: pasicr :: Replies: 3 :: Views: 862
I wouldn't attempt it for several reasons:
1. the signals feeding an LCD are very different to those used with an LCD. For example you will not have individual segment conections and digit drive signals.
2. it looks like you have one (1.5V) or two AA cells (3V) which isn't enough to drive most led displays. Each segment in a standard display has s
Elementary Electronic Questions :: 09-22-2013 08:11 :: betwixt :: Replies: 4 :: Views: 772
hello i have example which done by me. i have toggle led in ISR u can place ur code in ISR
Microcontrollers :: 09-21-2013 08:22 :: embpic :: Replies: 2 :: Views: 655