USB is Universal Serial Bus. If your question relates to a specific chip, please mention it in your question.
7
votes
1answer
89 views
in a USB cable, is it OK to swap the D+ and D- wires?
I heard that D+ and D- are differential signals, does it matter if I swap them when connecting a USB device to the computer?
0
votes
1answer
31 views
Amperage in a USB AC-to-DC power converter
so it was my understanding that USB was standardized with 5 volts (V) at 1 Amperage (A), but I've seen wall adaptors with 5V and different Amperage including 1A, 1.1A, 1.5A, 2A, 2.1A, and as much as ...
3
votes
1answer
54 views
Can an ATX PSU power a USB port directly?
I'm going to build a benchtop PSU from an ATX PSU, and I would like to add a USB charging port on it. It should be able to power an Arduino or charge my (non-Apple) phone. (I know Apple devices ...
7
votes
1answer
138 views
What separates a “good” eye diagram from a “bad” one?
I'm running some USB verification testing at work, and the Agilent oscilloscope I'm working with returns a nice summary of pass/fail statistics along with a pretty eye diagram. Since the pass/fail is ...
0
votes
3answers
48 views
USB Solarpanel read current with python?
I'd like to connect a small solar panel (2v 50ma) to a USB cable and measure the output on python. Now I was wondering if this would work and how to make it work.
How many volts can I send into my ...
0
votes
0answers
14 views
USB Solarpanel read current with python? [duplicate]
I'd like to connect a small solar panel (2v 50ma) to a USB cable and measure the output on python. Now I was wondering if this would work and how to make it work.
How many volts can I send into my pc ...
1
vote
1answer
40 views
PIC + L6203 (Driver) problem (PIC Resetting)
I've created an electronic board to control a joystick (Yoke) using a PIC18f4550. The uController communicates with the computer via USB and send/receive all necessary data information to control 2 DC ...
3
votes
1answer
60 views
How can electromagnetic interference from a USB charger cause a capacitive touchscreen to malfunction?
Electromagnetic interference from a USB charger can cause a touchscreen on a mobile device to malfunction, with symptoms such as reduced sensitivity or spurious touches. As an example, see ...
0
votes
1answer
53 views
External powered USB hub
I am planning on building a quite large USB hub, which final use is to connect, charge and sync let's say 40 iPads. The iPad electrical specification from Apple states that each unit needs to have ...
-2
votes
0answers
47 views
How would one make a USB 3.0 Camera work with an FPGA, what is required? [closed]
How can a USB 3.0 camera be made to work with an Altera FPGA? What are all the ingridients and possible routes that one can take to make such a camera work with an FPGA so that the FPGA can read the ...
8
votes
2answers
241 views
How can I check input of USB?
I have following wire as shown below, one end has male USB connector and other end has four wires. I know, when connected to laptop, the RED one acts as voltage source and BLACK as ground. If I give 2 ...
2
votes
1answer
91 views
Building a battery pack, how do I recharge it with USB?
I am working on a small 12V boombox project and trying to figure out how I should approach the power supply. I have some goals that I want to achieve:
Should be able to be charged with an iPhone ...
4
votes
2answers
76 views
If I plug in a USB wall adapter but don't have a device hooked up, will it use power?
So let's say I have a phone and a USB Wall Adapter. If it is plugged up, but I don't have my phone hooked up, will it use power? And if so, will it be a noticeable amount when left plugged in for ...
0
votes
0answers
64 views
Raspberry Pi not successfully booting with USB hub
I recently got my Raspberry Pi Model A, I decided to use a normal USB hub (with no external power source), it appears to be supported, as well as my other devices on the hub. My Pi has booted before ...
1
vote
1answer
86 views
At which level of voltage is USB device disconnected
I have to realize a USB switch on my own. For security I have a chip (TPS2052) which has short - circuit protection and is controlling the current. My problem is:
When I switch from one USB port to ...
0
votes
1answer
66 views
Run a processor through USB
I am really new to hardware design but have a fairly good knowledge of analog and digital circuits. I have only built one automated car using an Arduino board for a lab. However, I have really good ...
1
vote
1answer
54 views
DC 5V to 3.3V DC-DC Step-Down issue
TL;DR : The output voltage from my 5V DC to 3.3V DC stepdown seems to output 4.5V DC - why?
Background:
I'm trying to power an Airport Express from USB rather than a wall outlet. I have discovered ...
1
vote
1answer
65 views
How exactly do USB audio interfaces interface with a computer? (specifically ADC)
I have seen the likes of M-Audio fast track and similar devices that somehow covert an analogue voltage audio signal to a digital data stream which you can connect via USB to your computer. If I open ...
0
votes
0answers
70 views
USB over FFC (flexible flat cable), where to place termination?
I have a design with a NXP LPC 4330 microcontroller using the USB port in high speed mode (acting as a mass storage controller). Due to the mechanical constraints of the system, the USB port must be ...
3
votes
2answers
62 views
How can I test the amount of power I can draw out of a USB charger?
I've got several USB chargers where the labeling has worn off. I'm interested in using some of these with a Raspberry Pi Model B, which needs at least 700 mA, as well as other devices with varying ...
0
votes
2answers
53 views
Nationally Recognized Testing Laboratories or UL Certification necessary for USB device
I'd like to import a USB device similar to a mouse to the USA and Canada, does it need to be certified by Nationally Recognized Testing Laboratories (NRTL) or UL? Does it make a difference if the ...
1
vote
1answer
68 views
Powering off USB - question about grounding
I have a female USB connector that I want to use to power a little piece of electronics I'm working on.
I have a USB cable plugged into a computer with the socket on the other end and I'm using my ...
-3
votes
0answers
57 views
Why does my computer not recognize IOIO Mint? [closed]
I'm trying to connect my newly bought IOIO Mint to a Windows 7 PC using USB connection according to this tutorial.
I plugged in the USB cable (orange LED is on), then turned it on (red "Power" LED is ...
1
vote
1answer
66 views
Can I cut off the 5v output of the IOIO to the Android?
I'm working on a project using Sparkfun's IOIO for Android (https://www.sparkfun.com/products/10748) where power consumption is a concern. The IOIO board provides the phone with 500 mA charging if I'm ...
1
vote
5answers
643 views
10V from USB port
I want to connect a loading cell to the computer via USB port.
The recommended excitation voltage of the load cell is 10V, and USB output is 5V.
The current through the load cell is about 20mA at ...
1
vote
2answers
90 views
How should I build this circuit?
I have this homemade LED-USB thingy to illuminate my desk:
simulate this circuit – Schematic created using CircuitLab
I guess it's not a very technical schematics, sorry, I'm not even ...
-4
votes
1answer
62 views
How much max distance of SPI & USB & I2C and TWI(without any IC [closed]
How much max distance of SPI & USB & I2C and TWI(without any IC(my mean is directly)), and how can i amplify these?
1
vote
1answer
76 views
Use an active PS/2 -> USB adapter as USB-Serial Bridge
I'm working on a small robotics project where I need to enable my old phone (Nokia 5230, shows up as USB Serial port on Windows but USB cable is straight-through) to talk to an Arduino UNO R3 (doesn't ...
-2
votes
2answers
101 views
raspberry pi + USB Hub [duplicate]
I bought a cheap USB Hub Powered to connect my Raspberry Pi and two External Seagate HD (USB 2.0/3.0), but obviously that 400 mA is not enough for all this things.
So, I want to buy a new AC Adpater ...
3
votes
1answer
131 views
Safely extract power from USB
I am upgrading the lighting in a model with simple circuit which has 17 LEDs (approximately) plus one or two 555 timers. Presently, everything is powered by 3 AAA batteries. It drains between 150 and ...
3
votes
2answers
185 views
What is the purpose of capacitors and resistors in this USB bus?
Trying to understand the purpose of the capacitors and resistors in this bus powered configuration for the FTDI chip, I think the capacitors are for filtering high frequency noise, not sure what the ...
1
vote
3answers
105 views
Custom USB Impedance question
I'm looking at making my own USB cable for a project. The primary issue I'm having is that I'm getting a lot of capacitance in my cable between D+ and D- (400ish pF) which is enough to throw off the ...
3
votes
1answer
200 views
Working with FTDI library for accessing FPGA memory
I asked a related question here.
The board is Lattice MACHX02 1200 ZE.
I am using FTDI Library FTCSPI to access Lattice FPGA UFM through FTDI chip FT2232H. I configured the FPGA in SPI slave by using ...
3
votes
2answers
114 views
How to uniquely identify USB HID class device?
I would like to identify a USB keyboard uniquely(something equivalent to unique mac-id for the Ethernet cards) on a computer. Does the USB HID profile has a support for such identification ? If so ...
2
votes
1answer
89 views
What is the metal sheath surrounding a USB connector, and is it commonly connected?
I was tearing apart a mouse for repairs and noticed that the small plug for the USB connection had a fifth connection. This connection had a much thicker wire than the other four.
I assume it is ...
1
vote
4answers
171 views
How do I solder this USB Connector?
I bought this micro usb part: http://www.digikey.com/product-detail/en/10118192-0001LF/609-4613-1-ND/2785378
I need to solder it to a PCB that I designed, but I'm having a ton of trouble figuring out ...
1
vote
1answer
90 views
Home made USB charger based around LM2596: Smoothing caps
I'm embarking on building a home made mains USB charger based around an LM2596 DC:DC converter. I had a couple of Newbie questions.
Can I connect 5 or 6 USB plugs to the output of the LM2596 ...
2
votes
1answer
63 views
Searching for standalone unix development board to connect DC motors
I though a bit about the board and came to the conclusion that it may be more intelligent to use a stand-alone component which provides serial ports and an unix os which I then can control over the ...
0
votes
1answer
107 views
Programming an NXP - LPC1313FBD48
I was planning on flashing my mini os onto my NXP - LPC1313FBD48 (here is a link to where I bought it) but I wasn't really sure how. So I asked but I was told that I would need a serial to usb ...
1
vote
1answer
56 views
Listening in on ANT+ device communication?
I have TACX iGenius cycling trainer, which uses an ANT+ USB stick to control the resistance on the bicycle wheel. (You play a video in their software, and it matches the resistance on the wheel to ...
2
votes
1answer
75 views
Where do I lookup values for building an USB HID descriptor?
I'm trying to educate myself a bit on creating a USB HID descriptor in C for a PIC32 USB project I want to attempt.
I've downloaded the HID Usage Tables document from ...
0
votes
3answers
161 views
Three-prong / USB power outlets in wooden desk [closed]
I am trying to mount a strip of three-prong outlets and a strip of USB charging outlets on an old wooden desk. I can handle the carpentry aspect, but I am struggling with the electrical aspect.
I ...
1
vote
1answer
70 views
USB interface to bluetooth interface for digital scale
I've got a situation where I need to communicate wirelessly between a bluetooth-enabled Android device and a digital scale which can be accessed digitally via USB.
While normally I would be happy to ...
0
votes
2answers
76 views
USB Lamp, controlled by linux driver
I want to build a simple USB lamp (maybe colored LED lamp) which will be controlled by PC. So, actually, i want to get practice in linux kernel modules development, but i need to get appropriate ...
0
votes
0answers
60 views
Implementing USB On PIC24
We want to implement USB on our PIC24 based embedded system.
Hardware: All done
Firmware: USB part is currently Non-existent
My role: Make it all work
Questions: The protocols are very complex
...
1
vote
2answers
106 views
How does a computer (or USB device) detect that there is a new/lost connection?
I have two computers, a USB keyboard and a USB mouse. I want to build something that lets me switch the USB devices between the two computers. My approach would be to buy a new powered USB hub and ...
0
votes
2answers
97 views
Arduino Clone is not talking to my Mac
When I plugin my Osepp Uno (off-brand of Arduino Uno), the LED flickers a bunch, then the RX and TX lights do the same. But when I
ls /dev/ | grep -i usb
I get ...
0
votes
1answer
71 views
How simulate trick htc wildfire charger (get max current)
I have an HTC wildfire phone and I'm looking for way to trick this HTC to think it's connected to the original charger. I don't have original so i can't open it to measure. Right now for charging I'm ...
-1
votes
2answers
155 views
Multiple 2A USB Mains powered chargers [closed]
I'd like to know why there are no mains-powered chargers that can charge multiple usb devices at, say, 2A and 1A?
I'm after something that can charge 2 tablets that ask for 2A and 2 phones on 1A, so ...
0
votes
1answer
23 views
Are there any DIP alternatives to the FT232R?
I'm currently using an Arduino on a breadboard, interfacing with it via a FT232R chip mounted on a breakout board. For my final design I'd ideally like to use all thru-hole components for ease of ...
