USB is Universal Serial Bus. If your question relates to a specific chip, please mention it in your question.

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1answer
28 views

How does USB 3.0 negotiate power states?

I noticed, in another question, a comment regarding USB power states. I know that USB 2.0 negotiated power by tying the D+ and D- lines to specific voltages but I can't seem to find any information ...
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1answer
30 views

how to increase output current? [on hold]

I have several car chargers but all have 5v, 500-800mA output current. I want to increase the output current to 1A. So that my cell phone charges quickly. Help me what to change or add component to ...
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1answer
28 views

STM32F102 USB Programming

I am currently designing a board for a STM32F102 chip which needs to be able to use the USB bus to transfer data while the chip is running. However I also want to be able to program the chip through ...
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3answers
105 views

Can the power source for a USB device be different from the data source?

I was wondering if the data source (USB Host) for a USB device has to also deliver the power 5V circuit e.g. data and power need to have a common ground. Or can I connect the data lines to the data ...
0
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1answer
76 views

RAW USB data over IP even through WiFi

For very special project I need to transfer data from a USB device to another system remotely as RAW "commands". The source device is something like a security dongle (not exactly but is a good ...
1
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1answer
24 views

SRD-05VDC-SL-C 5V DC relay not working with XY-DJM-5V

I'm just a beginner and need some assistance. below is a diagram of a 4CH reciever which works fine with some leds and it reports 5V positive on Data0 when holding channel 0 on the transmitter. What's ...
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3answers
161 views

Why usb to serial port converter can’t program avr microcontroller?

With a serial port or parallel port in pc programming avr microcontroller is very easy and cheap. Problem is, no modern computer come with serial or parallel port. So, usb to serial converter should ...
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0answers
35 views

How to setup a usb Host device

How can i setup a usb host device with pic32MX795 with a pendrive as a device . I have been able to detect the pendrive and enumerate it partially , but cannot create a file on the pendrive . I am ...
4
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1answer
66 views

What is the ideal way to handle data pins D+ and D- on a USB power adapter to be compatible with fast charging on devices?

I have found that many USB wall chargers use a resistive voltage divider to set the D+ and D- pins to a specific voltage, usually between 2 and 3 volts. Other USB wall chargers short the D+ and D- ...
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1answer
50 views

Is an USB-to-UART converter different from an USB-to-RS232 converter? [duplicate]

I have a USB-to-RS232 converter. The GND, TX and Rx pins of the RS232 I connect to GND, Rx and Tx on a development board I have. I've set the right baud rate, flow control and other settings in my ...
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3answers
137 views

Why would the output voltage of a 5V SMPS (USB charger) increase with load?

I've been using a USB voltage/current measurement device to evaluate power consumption of USB devices and performance of USB chargers and batteries. Most of the USB power supplies I've used are ...
2
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1answer
38 views

USB Interrupt and Isochronous transfer bandwidth concept

I read in the USB spec and other USB materials on the web that interrupt transfer mechanisms (for devices like mice/keyboard) are guaranteed a 'bounded latency'. Whereas the isochronous transfers ...
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0answers
19 views

USB host bulk endpoint setup

Using PIC32MX795F512L as host , for MSD class trying to connect to a pen drive using MLA code , the enumeration is complete , but bulk transfer doesnt work .Cannot read the sector size . I faced ...
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1answer
30 views

USB max devices for host and hub

I am new to USB. I am studying the USB in a Nutshell Guide and the relevant parts of the USB2.0 spec. As per what I have read, a max of 127 devices can be connected to a single bus. As only one host ...
0
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1answer
20 views

Drivers rquired for GSM module [closed]

I'm woking on a GSM module which has a serial port. I'm using a TTL converter to convert it into USB to the laptop. the software I am using is terminal but I'm unable to select the port in the ...
0
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1answer
62 views

Good volts and amps but phone still charging slowly

I am really new to the EE game and am still tinkering. I have built my own portable DC power source similar to a Minty Boost from scratch and plugged it into the USB port of my Galaxy S3 and it ...
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1answer
30 views

UM232H-B Breakout Module as a parallel port

I want to build something like UM232H-B Breakout Module. This configuration uses an FT232H, to convert usb to serial/parallel. I don't know whether it works with FPGA parallel port programming cable ...
0
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2answers
79 views

I want to send data to seven segment display without micro-controller

I'm new to embedded systems I want to send data to seven segment display from my pc could i connect the seven segment display to my pc via serial or usb port or i have to use a micro-controller ...
0
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1answer
32 views

Mini-DIN to USB-Power [closed]

I have an old laser printer, HP LaserJet 2100, with 2 ports: a parallel port; an 8-pin mini-DIN female "LocalTalk port" connector: I am using a Raspberry Pi as a network print server. The Pi ...
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0answers
20 views

USB in Nucleo F302R8

I'm using the Nucleo F302R8 to build the firmware for a new board I'll develop using the same MCU. I'm trying to use USB CDC to have a VCP. I've started with CubeMX with the Nucleo F302R8 template, ...
0
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0answers
52 views

USB Audio Stream to Codec

I have been trying to design a USB Audio Interface with an Atmel SAM3U microcontroller and I think I have hit a wall in my thinking process. As a sidenote, I'm relatively new to the world of ...
0
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1answer
40 views

Plug-and-play usb-midi controller. How?

I am wondering how plug-and-play usb-midi controllers are created? To the moment I've created a simple midi controller based on Arduino Uno, but I am not able to use it directly. I have to use ...
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1answer
62 views

What USB class should I implement?

I'm playing around with STM32F4 Discovery board and libopencm3. I want to send data acquired from ADC channels over usb and display some charts on the computer. After doing some research on USB class ...
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2answers
100 views

Are all USB “audio adapters” DAC's? Can USB ports be used for analog output?

Kind of a weird question.. Background: My motherboard has started producing weird static(buzzing) noises on the audio output(3.5mm jack), it's not noticeable when using headphones, but on speakers it ...
0
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1answer
43 views

What's the maximum size of a USB descriptor?

I would imagine it has some theoretical limit right? I'm just curious so I can gauge how many endpoints a device can have based on the space used for all the other configurations. Or is it limited ...
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0answers
28 views

Tiva Launchpad for USB Read/Write

Is it possible to write/read text files on a USB Mass Storage Device using one of the USB ports on the Tiva Launchpad?
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4answers
91 views

What is this electronics component?

What is the yellow component shown here? This is off a Outlet USB phone charger.
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3answers
99 views

How do USB charging and “smart” charging ports (e.g. Anker's PowerIQ) work?

Software engineer with a hobbyist understanding of EE here. I've noticed lately lots of claims from producers of USB battery packs that their ports are "smart" and "identify the device" to "deliver ...
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1answer
105 views

keyboard and mouse interface

How do I interface a microcontroller with PC USB so that I can imitate the keystrokes and movement of keyboard and mouse. I've heard of software fixes, but is there any IC which can mimic the ...
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1answer
48 views

Why can some devices ignore the USB 10uF inrush limit?

In general, USB recommends that the maximum capacitance placed on the end of the device is 10uF, in order to reduce the "inrush current" when the device is plugged in. While it is possible to use ...
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0answers
54 views

Read and write FPGA registers via USB or Ethernet

I'm working on an FPGA project on an Atlys Spartan 6 board. I'm programming it in VHDL. I have two 32 bit registers, one for output, the other for input. I need to be able to, respectively, read and ...
1
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1answer
40 views

USB Hub bandwidth problem [closed]

I will use a Beaglebone Black with a powered USB Hub to control a USB Microphone (PCM2912A) and a USB HDD. The task consists in recording and writing the Audio directly into the HDD... Will I have ...
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0answers
17 views

Force disable USB connection state in system after power on

Title : Force disable USB connection state in system after power on. How to disable USB connection whenever system power on. I know USB 1.1 and USB 2.0 have 4 line Vcc DP+ DM- GND Setting DP+ ...
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0answers
34 views

homemade hub dynamo usb charger

I just made an usb charger to connect to my hub dynamo. ->voltage rectifier -> smoothing capacitor -> low voltage drop 5V regulator -> female usb port So now I can power / charge my mobile phone and ...
0
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1answer
48 views

Coplanar waveguide for differential trace calculator

Although there are plenty of free impedance calculators out there, I'm struggling to find one that can solve impedances for a differential pair using coplanar waveguide. Anyone know of any free ...
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0answers
50 views

Do I need a resistor for powering a 3-12v dc motor with USB 2.0

I'm trying to make a project from instructables: http://www.instructables.com/id/ATtiny8545-POV-Display/?ALLSTEPS And the guy uses resistors for his usb cable and now I'm not sure if I need to use ...
0
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1answer
95 views

Can I test a USB port with a multimeter? [closed]

After a recent thunderstorm (Derecho), we had a power outage. After power restored, I noticed my desktop's USB ports (and a PS/2 port) were not responding, even at a BIOS level. Tried a known good ...
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1answer
73 views

Change USB Device Description

Can you change an USB device's descriptors? My boss wants to change a USB diagnostic device's name. I thought changing the USB Device Description would be sufficient, but I don't know if it is ...
0
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2answers
90 views

Is it possible to change a USB's enumerated descriptors (from the OS side) after plugging it in?

I don't mean as in change the descriptors built into the device, but the descriptors that the OS has enumerated. Can this be done from the OS side without touching the USB device? For example, can I ...
0
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3answers
66 views

Olimex/ATMega328 Reading from UART and sending to USB

I'm getting frustrated with my electronic knowledge, because I want to do this simple thing: Olimex 328/ATMega328 reads data from UART (Olimex MOD-PULSE or whatever) and forwards it to the USB Port ...
1
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1answer
64 views

How can I create a DC-DC voltage multiplier [duplicate]

I want to take the 5V output from a USB port and make it 12V, so that I can run a cooling fan which is 12V. Is there any circuit I can make at home myself? If the output voltage is not exactly 12V, it ...
0
votes
1answer
51 views

How to program ATmega2560 chip

This is ATmega2560 http://www.atmel.com/devices/atmega2560.aspx How can you program this? Using Arduino as ISP? USBasp? Also, since this chip in a QFN (I think this is what it's called), then how do ...
2
votes
1answer
44 views

Raspberry Pi and USB modem - can I connect it like this?

As some of you know - Raspberry Pi has only 100mA available on USB ports. I want to connect USB modem (that takes > 500mA sometimes) to my Raspberry without powered USB hub. I have: Raspberry Pi ...
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0answers
40 views

Understand the shielding of a USB device

I have a GPS PCB which has regular USB pinouts (GND, +5V, DATA- and DATA+), but in addition has one stranded wire which is connected to USB type A plug. Marked as "USB connector" on the image: What ...
1
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1answer
54 views

USB port suppressor

I am using SN65240PWG4 USB PORT SUPPRESSOR. This is a part of the schematic: (I have connected pins A (6) and B (8) to D- and D+ USB pins. C and D I must connect to the supply) In this schematic ...
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4answers
123 views

Why is the led that I hooked up with my laptop blinking?

I connected a led to my laptop through a USB cable. I connected the red wire to the positive end of the LED and the black wire to the negative and of the LED. Why does the led keep blinking (pulsing) ...
4
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1answer
792 views

Could I connect USB wires to this mysterious device?

In a treasure box, as I call the boxes full of old computer electrical parts, I have found a device marked HannStar MV-4 94v-0 0611 E89382. I'm intentionally linking you to google search so that you ...
2
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0answers
88 views

Are any USB-to-SPI *slave* bridge chips readily available?

I would like to interface a battery-powered device to USB, without requiring users to install drivers. Data transfer requirements are moderate, so the ~60kbytes/sec of HID mode would be fine, but I ...
0
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1answer
53 views

How to set up a LiPo battery to be able to charge and discharge from the same circuit

I am new to using rechargeable batteries in electronics projects. To give some background on the context of the project, I'm trying to build a solar charger/power pack for a cell phone. My problem is ...
0
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0answers
46 views

Embedded host driver or RS232 host-side converter for CP210x USB device?

I currently have a device that uses a CP2102 UART-to-USB converter to send information to a PC. Now I want to instead have it send information into a dongle (not part of the actual device), which will ...