All Questions
176,073
questions
46
votes
11
answers
61k
views
Cheapest FPGAs? [closed]
How cheap do FPGAs get? I know they're more expensive than microprocessors of comparable capability, but I wonder if there exist FPGAs that could contain a Microblaze soft core running Linux, while ...
- 12.5k
7
votes
8
answers
807
views
Any advice on reading datasheets [closed]
After my embarrassing mistake by having the component in backwards, I'm wondering if anyone has advice for the newbie (or expert) on reading datasheets.
What conventions are there which aren't ...
- 428
5
votes
3
answers
364
views
Choosing a switching device
I am overwhelmed with the variety of switching devices. MOSFETS/BJTS Relays(mechanical/solidstate),optoisolated solutions, etc..
I need to support 15V, 60A bursts, should be high efficiency, and ...
- 2,326
3
votes
4
answers
2k
views
Desoldering an SON package
I have recently discovered that my AVR Dragon has a busted voltage regulator (see this). I am trying to remove the voltage regulator IC so I can perform the mod specified on that page, however it is a ...
- 4,987
11
votes
4
answers
1k
views
How do I detect open-source licence violations by companies?
Let's say I have an open source project with a license that prohibits commercial uses. Then comes along a commercial product with striking similarities in functionality/hardware.
How would I go ...
- 2,326
8
votes
4
answers
3k
views
I don't get the Arduino concept
I have been struggling with making an Arduino for a while (was successful in making a breadboard version using an ISP programmer cable). They say that the Arduino bootloader is made so that no ...
- 3,847
17
votes
4
answers
8k
views
How can I tell how much juice a LiPo battery still has in it?
Suppose I have a circuit that draws its power from a LiPo Battery.
I would like to know how much power the battery still has in it.
Ideally a circuit of power level to voltage will be best .. this way ...
Atrigen
8
votes
4
answers
1k
views
Arduino with cell phone
I am trying to simulate button presses on a cell phone by using the Arduino to complete the button circuit thus simulating a button press. I figured out I have to use a transistor but I can't get it ...
- 221
4
votes
3
answers
443
views
SBC Recommendations [closed]
I want to get started with embedded development and for my first project I thought of making a caller-ID type of appliance.
Here's why I want a SBC for this:
I want to be able to locally serve this ...
jfl207
5
votes
2
answers
883
views
LM335 doesn't seem to work
I'm relatively new to electronics, and I'm trying to make a thermometer using a LM335 temperature sensor. By reading the datasheet I thought it was simple, connect up 5V to a resister, then to the V+, ...
- 428
7
votes
3
answers
3k
views
AVR self-programming
According to the datasheet, the ATMega168 can only execute self-programming instructions when running code from the bootloader block.
Once the bootloader is complete and the application starts, can ...
- 28.6k
22
votes
7
answers
3k
views
Identify processor type from raw binary code?
Not really related to chips, but hopefully I'll get some directions to follow from here.
I got a chunk of code, but I don't know what processor it intended for.
Are there tools available that can ...
- 395
14
votes
10
answers
52k
views
Arduino hooking up LCD without POT
I am using this LCD:
Plus I am using an Arduino. I am trying to hook this up but without a 10K pot. How is this possible? Every tutorial I found involved the 10K potentiometer
- 221
7
votes
1
answer
1k
views
Shutdown for LT3080 current source
I would like to use a LT3080 as a current source (see datasheet page 17 in Typical Applications Section). However, I need to be able to shut it off. Since $$I_{\text{out}}=10\mu\text{A} \times R_{\...
- 8,249
8
votes
2
answers
188
views
Resources to understand robot locomotion and Gait functions
Recently I have been watching Robert Full's talks on TED. He has some obscenely interesting works on robot locomotion. This has intrigued my curiosity and I have been trying to understand his works. I ...
3
votes
3
answers
971
views
Piggy-backing off power amplifier outputs
My motor-scooter has a built in radio, with a small speak either side of the front panel, below the handlebars. It's a JonWay, i.e. cheap Chinese, so I suspect the radio is more suited to developing ...
- 261
3
votes
1
answer
467
views
Rotation span of SparkFun ROB-09065 servo
Does anybody know what the rotational span of the ROB-09065 servo from SparkFun?
And even better, is there a datasheet available anywhere?
- 728
7
votes
5
answers
464
views
Removing digital noise in software
I have a design which expects a TTL level square wave from a radio reciever which is fed into a microcontroller. There is some TTL level noise as no encoding is done on the transmit end. I was ...
- 4,987
21
votes
14
answers
99k
views
How to clean a potentiometer?
I have a couple of potentiometers that haven't been touched in quite some time. In fact, probably not in 15 years. So now they produce noisy output, presumably from oxides or some other crud that has ...
- 19k
4
votes
5
answers
8k
views
How to Determine a PCB's Power Requirements?
Disclaimer: I have very little (almost none, really) electronics experience.
I purchased a set of IR illuminator boards off of eBay. The only information that the seller provided was that the board ...
glnsdre
8
votes
2
answers
518
views
logical not circuit?
I don't have much experience with electronics, but I think what I want to do could be cobbled together from a Radioshack.
I have a Dig 5006-IP automatic sprinkler controller. It controls 24V DC ...
frank
4
votes
1
answer
13k
views
Reading a pin as an input on AVR XMEGAs
I have been messing with AVR's XMEGA line. They are pretty amazing microcontrollers. However, Atmel changed much with this new line. I am trying to detect a pin going low.
I have tried to set the <...
- 547
6
votes
2
answers
1k
views
ATA Interface for PIC
I've been considering using a NANDrive by SST in a new design, however I wasn't sure how complicated it would be to connect a PIC to the ATA interface on the NANDrive. I did a quick Google search and ...
- 3,869
5
votes
2
answers
3k
views
FTDI Basic Breakout - 5V
Can this board be used to upload sketches to the Arduino. I tried by hooking the TX port on the FTDI Basic Breakout to RX port(Pin 2 on the Arduino) and RX port to pin 3 on the Arduino. But so far I ...
Tim
3
votes
3
answers
150
views
Prototype Options For Medium Current Application
I'm looking for the best option to develop a medium current (approx 1-2 amps) prototype board.
Should I be using perfboard, Vero/stripboard or etching a custom board? Or are there any other options ...
- 31
12
votes
2
answers
4k
views
Reading a Rectifier Diode
How do you read the numbers on a rectifier diode? It only says "06" (or "90") on it (twice, once horizontally and once vertically). I figure I'm supposed to assume this is a 1N4006, but I'm a bit of a ...
- 221
6
votes
2
answers
4k
views
Does CPU pipelining always imply a multicycle datapath?
I'm studying the MIPS CPU and I have a very basic question about the datapath. Since the MIPS CPU uses a 5 stage pipeline, that means that the pipeline is using a multicycle datapath, correct? If a ...
Henley
18
votes
2
answers
4k
views
Solder Flux Classifications
I was at Fry's yesterday, looking for some thin solder to use on an Adafruit kit with through-hole components.
Two of the solders I found were labeled RA Flux and No Clean, respectively. An engineer ...
- 3,720
2
votes
1
answer
626
views
What type of connector to use for pressure contact?
I'm designing a robot gripper that needs to pickup an electronic device (the size of half a laptop) and move it around. The problem is that when the device gets picked up, I need to establish a USB ...
- 791
8
votes
3
answers
885
views
Passive listening to USB communication
Is it possible to passively listen on low speed USB communication?
Suppose I connect a logic analyzer to D+ or D- line, will I see a valid data?
- 395
4
votes
1
answer
741
views
When are MIPS control signals generated?
Are the control signals for a given instruction generated within a single cycle
for the pipelined, the multicycle as well as the single-cycle implementations of the MIPS32 datapath?
I think they ...
Henley
-1
votes
1
answer
223
views
Robotics custom search engine
I made a google custom search engine:
robot cse. Any sites I should add to the list.
http://forum.microchip.com/
http://www.avrfreaks.net
http://www.societyofrobots.com/robotforum/
6
votes
2
answers
1k
views
Dual Role USB device on AVR
Is it possible to run both USB Host and USB Device controllers on top of an AVR (ATMega64)?
Specifically, what I'm looking for is to receive data from a usb keyboard, and simultaneously sending ...
- 395
4
votes
2
answers
382
views
Support for MSP430x5xx processors on MSP430-gcc
How would I add support for a new MSP430 processor type on MSP430-gcc? E.g. msp430x5xx series.
I understand I must produce the relevant .h/.o files but how do I generate/integrate those in msp430-gcc ...
- 545
-1
votes
2
answers
806
views
Help me find an adapter USA --> Israel [closed]
I just bought a cat feeder from the united states, and brought it to Israel. Israel has 220V power sockets, and the device (that came with the timer below) doesn't fit, obviously.
The problem is I ...
18
votes
2
answers
5k
views
What are 'return' pins?
On a VGA connector, there are numerous 'ground' pins. Three of these are Red return, Green return and Blue return; But why does each color component have its own ground pin?
- 415
5
votes
2
answers
716
views
logic triggerable strobe light circuit
Does anyone have a circuit that will trigger a strobe light to flash in response to a TTL logic signal? Specifically, if I have a strobe circuit capable of flashing 1000 times per second, it seems ...
- 19k
9
votes
1
answer
2k
views
Isn't it overkill to use a regulated power supply for a nixie tube?
I've seen any number of nixie tube designs on the web that use regulated 170V supplies for the nixie tube anode.
Wouldn't it be possible to use unregulated, half-wave rectified 170V peak power for ...
- 19k
3
votes
3
answers
515
views
superscalar CPUs and data dependencies
I'm learning about superscalar CPUs and I had a question about that and data dependencies. Given the dependencies, RAW (read after write), WAR (write after read), WAW (write after write), when ...
Henley
8
votes
8
answers
6k
views
Can you base a computer around a 32-bit microcontroller?
We all have(mostly) 32-bit machines at our homes. But the 32-bit machines have a microprocessor in them. I was reading an article about the ARM Cortex. Its a 32-bit microcontroller. Now that intrigued ...
- 3,847
35
votes
2
answers
31k
views
33
votes
8
answers
50k
views
Current flow in batteries?
I am reading a basic electronics book: "There are no Electrons: Electronics for Earthlings" and I came across a clever passage about the fact that you need a closed circuit in order for current to ...
mike
2
votes
2
answers
4k
views
RJ45 Female Crimp Connector
Where can I find a female RJ45 connector that can be crimped to another cable rather than being soldered to a PCB or installed in a wall or plastic enclosure?
Something like this: http://www....
- 1,334
11
votes
4
answers
10k
views
Is it possible to drive TTL inputs from 3.3v microcontroller
I need a quick heads up on a problem I am trying to solve at work. I'm trying to connect to a parallel data port on an interface module we use to access smart cards. The port has an 8bit input and an ...
- 638
15
votes
1
answer
9k
views
What does the e3 or e4 printed on an IC mean?
So after staring at a few ICs today, I was wondering what the "e3" or "e4" stands for on the top of an IC. For example, here is an e3:
user1307
22
votes
4
answers
24k
views
Are Common Mode Choke Coils needed on USB?
I was looking over the schematic for the GumStix Palo 43 and noticed they used a common mode choke coil on the data lines coming in from USB.
I understand how this design can help remove noise coming ...
- 17.3k
4
votes
6
answers
1k
views
Write Once Memory
I've seen news articles talking about how SanDisk released Write Once Read Many (WORM) SD cards, but I can't find anywhere to buy them!
I'm thinking of building a project where I'll want to write ...
- 572
4
votes
2
answers
453
views
iCade - making it a reality
So I want to make my own version of the iCade Any thoughts on how I go about doing the hardware side? Has anyone done an unofficial version of this? I'm thinking a combination of:
Concave Button
...
- 5,030
9
votes
7
answers
5k
views
Best shunt resistor for power meter application?
Looking for a shunt resistor for measuring power usage and was wondering if anyone had any experience with these.
It should be capable of handling 110V/20A in-home circuit.
EDIT: Energy monitors ...
- 1,923
1
vote
4
answers
830
views
Programmer for Sanyo LC87F5NC8A Microcontroller
I want to hack my Samsung DVD player. But the IC used it a Sanyo LC87F5NC8A. I don't have a programmer that can dump or program this UC. Any advice ??
Seuros