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LED

Comp.Arch.Embedded is a worldwide Usenet news group that is used to discuss various aspects of Embedded Systems development.

We found 650 threads matching "led"

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The most relevant threads are listed first

Re: Micro Controller Advice/Help Needed

edgars - 16:15 14-08-08
> I'm building a small device that will talk to the world through a modem. > I've ordered the XE2422H devkit from XEComm. It basically has a RJ-11 > connector for the phone line and an RS232 connector for the controller. > > I need a cheap microcontroller that's easy to deal with which I can >...Re: Micro Controller Advice/Help Needed

Re: Two port implementation for a USB application consuming more than 2.5W

Kieran O' Leary - 16:37 12-08-08
"Brendan Gillatt" wrote in message news:WcqdnSoFnZqPBTzVnZ2dneKdnZydnZ2d@pipex.net... > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > sky465nm@trline4.org wrote: > > Ask port1 for 500 mA, and only then ask port2 for another 500mA. > > And report to the enduser what happends. L...Re: Two port implementation for a USB application consuming more than 2.5W

Re: Best solution to count RPM

MikeWhy - 16:32 06-08-08
"Joerg" wrote in message news:gPlmk.19292$Ri.16460@flpi146.ffdc.sbc.com... > > The OP mentioned motorcycles and he is in Italy. Have you ever seen a > Ducati or Moto Guzzi revv through several gears and go from zero to > freeway speed in just a few seconds? Some guys won't even stay i...Re: Best solution to count RPM

communication between PC and LED display

monika - 09:14 04-08-08
I am using a LED display which has following specifications: TFI-32x128-37RG 4.76mm Tri-color RS232/Ethernet 6.9"x26.22"x2" 4 lines of English I have connected it to PC com port and want to send data through the port. But when I use hyperterminal to send some data on the LED board, it is n...communication between PC and LED display

Re: computer-driven fans II

Frank Buss - 22:00 30-07-08
Ron Ford wrote: > It really helped me to see the pictures that come with these listings. > Temperature sensors look like cockroaches with eight legs. The first pin > is on the left as you read the name left to right, and it is symmetric > about the axis that would be the length. > > ...Re: computer-driven fans II

Re: Finding power - gnd shorts

Eric Smith - 20:14 23-07-08
rickman wrote: > As a matter of fact, the last day job I had the company had just > bought a $50,000 TDR. I am sure fixing a $150 board is exactly the > job they had planned for it. Even with that, I'm not sure it could > show me the short. It wouldn't easily identify the physical locat...Re: Finding power - gnd shorts

Ethernet Terminal I/O board

trex - 08:38 21-07-08
Hi everybody, I am trying to make a ethernet terminal I/O board. Basically making an x86 based 1U solution. I am trying to route the onboard ethernet connection via a patch cable (Cat6). this works but I also want the link/status leds. I did a simple PCB with two modular 8P8C Jacks with LEDs a...Ethernet Terminal I/O board

Re: Micro-SD card initialisation-problem - Resolved

Mark Borgerson - 13:17 19-07-08
In article , address@not.available says... > R.Wieser schreef in berichtnieuws > 487f9cf0$0$14357$e4fe514c@news.xs4all.nl... > > Hello all, > > > > I've connected a Micro-SD card to my printerport (using very simple 5v > to > > 3v voltage-step-down by three diodes and a re...Re: Micro-SD card initialisation-problem - Resolved

Timer ticks occurring much more faster

ratemonotonic - 12:04 09-07-08
Hi All , I am implementing RTC code on an AVR Atmega2560 I have a 32Khz clock crystal to TSOSC1 which is used by timer2 in async mode. I have configured the clock divide to 8 so the clock to the timer is 32768/8 = 4096. It is a 8bit so a interrupt should be generated every 16hz (4096/256). ...Timer ticks occurring much more faster

Re: Orthogonal matrix PS/2 kbd controller, low-power?

msg - 13:17 07-07-08
msg wrote: > larwe wrote: > > But why don't you buy a $10 > > rubber "rollup" keyboard off eBay and attach a couple of velcro strips > > to it? > > > Those rubber rollups were the first option I investigated... Also, they certainly aren't marketed as low-power, all...Re: Orthogonal matrix PS/2 kbd controller, low-power?

RS422 interface

svyamuna - 13:15 07-07-08
I am trying to interface two systems through RS422 link. There are only four lines connected between them (tx+/- & Rx+/-) and no ground. Independently both systems work fine but when interconnected and i try to communicate with each other there are some problems. initially master units Tx lines hav...RS422 interface

Re: tiny inductor with every bypass cap?

Terry Given - 19:04 23-06-08
Joerg wrote: > Terry Given wrote: > > > Joerg wrote: > > > > > Terry Given wrote: > > > > > > > Joerg wrote: > > > > > > > > > John Larkin wrote: > > > > > > > > > > > On Sun, 22 Jun 2008 13:03:09 +0000, Guy Macon > > > > > > wrote: > > > > > > > > > > > > > > > > > ...Re: tiny inductor with every bypass cap?

at91sam7: garbage on DBGU output

Roman Mashak - 22:20 16-06-08
Hello, MCU - at91sam7s64 toolchain - Yagarto (based on gcc-4.2.1) I have two distinct applications residing in the internal flash. The first one located at 0x100000, prints string and transfers control to the second application located at 0x104000, which lights the LED and prints a string...at91sam7: garbage on DBGU output

Re: Please suggest USB to RS232 adapter that works 100% [ FTDI rocks... and tunnels a serial port through USB ]

=?ISO-8859-1?Q?Glenn_M=F8ller-Holst?= - 02:49 13-06-08
CBFalconer wrote: > Tomás Ó hÉilidhe wrote: > ... snip ... > > Can anyone suggest a USB to RS232 adapter that does its job > > perfectly 100% of the time under Microsoft Windows, i.e. it > > trully behaves exactly just like any other serial port? > > Impossible. USB is not a serial p...Re: Please suggest USB to RS232 adapter that works 100% [ FTDI rocks... and tunnels a serial port through USB ]

Re: Connecting buttons with MSP430F2013 for Input Output with software

Jonathan Kirwan - 15:18 10-06-08
On Mon, 9 Jun 2008 10:59:54 -0700 (PDT), anmol wrote: > I want to connect 5 buttons with the MSP430F2013 MCU . I want to use > the buttons for input with a software . Please help and tell me how > to go about the task . If you have any tutorial , curcuit diagrams , > videos please give t...Re: Connecting buttons with MSP430F2013 for Input Output with software

AT921SAM7: jump to address in flash

Roman Mashak - 19:25 09-06-08
Hello, MCU: at91sam7s256 toolchain: Yagarto (based on gcc-4.2.1) First image XXX bytes length is burnt on the flash at the very beginning, by address 0x100000; second image resides on the flash at the (0x100000 + XXX). First image prints a short debug message out on DBGU port and then sho...AT921SAM7: jump to address in flash

Microcontroller-related engineering jobs

Jason Hsu - 20:49 02-06-08
I am seeking an electrical engineering position that has a heavy emphasis on microcontroller-based circuits. I believe these positions are usually called "firmware engineer" or "embedded engineer". I don't have formal experience in firmware/embedded engineering, but I do have informal experien...Microcontroller-related engineering jobs

Re: ARM9 STR912 IRQ woes (GCC/Eclipse/OpenOCD)

frikkiethirion - 11:39 02-06-08
Hi Richard > Sorry if this is a statement of the obvious, but have you checked that the > I bit in the status register is set such that interrupt are globally > enabled? I've double checked my startup assembly again and found in the section where the stacks are defined that no mention is m...Re: ARM9 STR912 IRQ woes (GCC/Eclipse/OpenOCD)

Driving tri-state LED matrix

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 08:18 30-05-08
The objective is as follows: uC pin set as output high: The Green LED lights up uC pin set as output low: The Red LED lights up uC pin set as input: Both LED's are off There will never be a time when both LED's are lit. Here's what I'm currently thinking of for th...Driving tri-state LED matrix

Re: MC68020 Embedded System HW Reset Problem - Need Help

Gene S. Berkowitz - 23:42 28-05-08
In article , jflan@tampaREMOVEbay.rr.com says... > > Hi - > I am hoping that someone could give some pointers as to how > and attack a reset (double bus fault) problem with an embedded > 68020 board that was originally designed by HP in a piece of > test equipment that was mfg back ...Re: MC68020 Embedded System HW Reset Problem - Need Help

Voltage from high impedence? (Newbie)

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 14:42 27-05-08
I understand from studying electrical science that the "ideal volt meter" would have infinite resistance and that it would draw no current whatsoever. However I know in reality that our volt meters have a little bit of conductance and thus a tiny bit of current flows thru them. It seems the h...Voltage from high impedence? (Newbie)

Re: Most suitable driver chip

Robert Adsett - 12:05 26-05-08
On May 26, 10:49 am, Tom=E1s =D3 h=C9ilidhe wrote: > On May 26, 12:11 am, Spehro Pefhany > > wrote: > > > I'm going to try get my hands on LED's that are bright in natural > > > daylight. Do you think I'd get much performance out of any such LED's > > > for 25 mA. > > > Ave...Re: Most suitable driver chip

Most suitable driver chip

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 18:12 22-05-08
I have a matrix of LED's, six rows and seven columns: X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X Across th...Most suitable driver chip

Re: Microscope Recommendations

Rich Webb - 16:29 22-05-08
On Thu, 22 May 2008 15:41:55 -0400, Blip wrote: > Now that almost everything I do is SMD stuff, I'm thinking about > trying to pick up a stereo microscope from ebay. They have pretty good > prices on 40x scopes. What value of magnification is best for checking > solder on boards? What are t...Re: Microscope Recommendations

Best way to get 2.5 volts from somewhere? (Vcc = 5 volts)

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 14:27 13-05-08
I've got a bi-colour LED. It has two pins. Internally it consist of two LED's in parallel except they face in different directions. I'm looking into ways of using one micrcontroller pin to control the LED as follows: Pin High = Light up Red Pin Low = Light up Green Pin as Input...Best way to get 2.5 volts from somewhere? (Vcc = 5 volts)

My idea of fully-portable C code

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 18:10 12-05-08
I've been talking about portable C programming lately, and I've claimed that I write fully-portable code. Many people here contested this claim, some more rudely than others, so instead of trash-talking back and forth I'm going to actually give an example of the way I code. In my most recent ...My idea of fully-portable C code

Pull up resistor on the gate of a PMOS

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 11:00 11-05-08
I have a tri-colour LED which consists internally of two LED's that have a common cathode. The device has 3 pins (two anodes and one cathode). Using one microcontroller pin, I want to light the LED either red, green or off. The microcontroller's pin states are intended to be as follows: Hi...Pull up resistor on the gate of a PMOS

Re: code optimiation

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 10:31 11-05-08
On May 11, 2:26=A0pm, Hans-Bernhard Br=F6ker wrote: > Tom=E1s =D3 h=C9ilidhe wrote: > > * Integer types may contain padding bits, and so sizeof(type) * > > CHAR_BIT won't necessarily give you the amount of bits in a integer > > type. > > On the contrary, that's exactly what it giv...Re: code optimiation

[EE] GPS logger with voice recording - Wear balancing for SD/MMC card needed?

wzab - 17:19 10-05-08
Hi All, I'm just working on the open source GPS logger with voice recording (to facilitate recording tracks for the http://www.openstreetmap.org project). The current architecture includes: GPS module - http://www.f-tech.com.tw/datasheet/GPS/FGPMMOPA2.pdf - first tests show, that it perform...[EE] GPS logger with voice recording - Wear balancing for SD/MMC card needed?

Re: PMOS in parallel with NMOS

Spehro Pefhany - 14:40 08-05-08
On Thu, 08 May 2008 19:21:02 +0100, John Devereux wrote: > Tomás Ó hÉilidhe writes: > > > On May 8, 6:35 pm, rickman wrote: > > > > > But what did you learn?  I can assure you that if you try to implement > > > a design like this in a job, your peers will not let you go to > ...Re: PMOS in parallel with NMOS

PMOS in parallel with NMOS

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 23:52 06-05-08
Let's say I have a microcontroller pin that will have one of three states: 5 V, 0 V or high impedence. Let's say I have a PMOS and an NMOS, and I connect their gates together. I connect the microcontoller pin to the gates. Now, when my pin is high, the NMOS will turn on. When the pin is lo...PMOS in parallel with NMOS

Loss of synchronisation: Are the chips reliable?

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 14:44 06-05-08
A lot of you are familiar with the method of using a shift register to multiplex a matrix of LED's. My college project this year was to make a Connect4 game consisting of a 7x6 matrix of LED's. I had two choices for implementing the display: 1) Use two pins from the microcontroller ...Loss of synchronisation: Are the chips reliable?

Re: Just assume that it's not in a defined state?

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 14:53 04-05-08
> Just out of curiosity - what are the other pins on the PIC being used > for? I've 12 pins available altogether: * 7 are going to LED's. * 1 is clocking a counter. * 3 are taking input from buttons. * 1 is turning a piezo speaker on and off. Here's my current schematic: http://f...Re: Just assume that it's not in a defined state?

Re: Simple Clockable Decoder Chip

Rocky - 14:37 03-05-08
On May 3, 7:44=A0pm, Tom=E1s =D3 h=C9ilidhe wrote: > Let's say we have an 8-Bit shift register. We reset it so that its > outputs are as follows: > > > Then again I could always just use two of these chips, but I just > thought I'd check to see whether there was a more suitable chip...Re: Simple Clockable Decoder Chip

Re: Inputs left floating at the very start

linnix - 11:37 03-05-08
On May 3, 5:37=A0am, Tom=E1s =D3 h=C9ilidhe wrote: > In college, I was always told not to leave input pins floating on a > device such as a 74HCT chip. I was told that the device might behave > erratically if any of its inputs are floating. > > I have the PIC16F684. One of its inputs go...Re: Inputs left floating at the very start

A few novice questions

=?ISO-8859-1?Q?Tom=E1s_=D3_h=C9ilidhe?= - 15:27 02-05-08
I've a decent enough knowledge of electronics but I'm not very big up on what's being used today in embedded systems. For instance, in my college course, we use chips in the "74HCT" family and we use transistors such as BC337 and TIP121 as switches. I've been asking around and it seems tha...A few novice questions

Re: Task priority for UI task handling menus and other controls

Vladimir Vassilevsky - 19:32 01-05-08
Steve Watt wrote: > [0] OK, a continuous 200 ms lag of response in my joystick would make > landing on a carrier somewhat harder. On the other hand, if it was > always there, it could be trained around and compensated for. The occasional delay in the reaction of the user interface ...Re: Task priority for UI task handling menus and other controls

Re: Debugging: Am I a dreamer. . . ?

Ed Prochak - 09:02 30-04-08
On Apr 29, 10:21 pm, Tim Wescott wrote: > On Tue, 29 Apr 2008 16:45:34 -0700, Tom=E1s =D3 h=C9ilidhe wrote: > > I've been programming in C for the best part of a decade now but it's > > only within the last year that I've really started doing embedded > > systems programming. > > >...Re: Debugging: Am I a dreamer. . . ?

Driving a led without a series resistor (PWM technique)

02:52 30-04-08
Hi, I'm designing a board where the microcontroller is supposed to drive 10 red leds and 4 optocouplers. I would like to drive the leds and the opto's without a series resistor using the PWM technique. I made some experiments and all seems to work fine in the lab. 1. The supply voltage i...Driving a led without a series resistor (PWM technique)

Re: Luminary Cortex ARM toolchain thoughts?

FreeRTOS.org - 17:34 26-04-08
"larwe" wrote in message news:5f9543eb-c46c-4d3b-b4aa-dc69b743a8c5@b9g2000prh.googlegroups.com... On Apr 26, 8:14 am, "FreeRTOS.org" wrote: > > Just for completenesshttp://www.rowley.co.uk > > > > (Used that lots too, very nice, clean, easy tool. Also uses the > > CodeSourcery com...Re: Luminary Cortex ARM toolchain thoughts?
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