Questions tagged [usb]
USB is Universal Serial Bus. If your question relates to a specific chip, please mention it in your question.
3,491
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FTDI FT234XD not recognized
I designed a PCB that incorporates FT234XD (Datasheet) USB-UART converter but no matter what I tried, I couldn't get it working. Host computers does not even react let alone give an error so it's ...
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Connecting another Arduino to RX pin, bypasses first Arduino.,
I've got two Arduinos. One connected via USB to a PC, then another with its RX connected to the RX of the first Arduino. Both have a common ground through through the USB and another wire connecting ...
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Not just another USB voltage question [closed]
I have a travel razor that charges with a USB–A cable, but the razor is the proprietary Norelco type connector. So I thought I'd solder a USB–C directly onto the board in the razor.
I checked the ...
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Is the voltage on the negative of a differential pair actually below the ground voltage used to generate the signals?
Apologies if it’s obvious but I always hear that differential pairs have a negative and positive waveform (one on each line) that’s opposite. Now I get that you could choose whatever value or point “...
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How to force a SLOW charge over USB
It is often asked how to charge faster over USB, but I want to do the opposite, charge overnight as slowly as possible, to preserve battery life.
If at all possible I'd like to limit charge current to ...
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Can I force the DD port in the TI ISOUSB111 Isolator to be downstream-facing?
I am new to USB comm. protocol. I am using a TI ISOUSB111 Isolator. The basic setup seems simple enough but it is not working for me as expected, it does not enable recognition of USB devices. I ...
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What are the consequences of connecting the USB-C 3 TX+ to a 3.3V plane?
I would like to understand the consequences of pulling the TX+ pin of a USB-C 3 connector to 3V.
For context, a community of retro-gamers has taken to building controllers & similar items that ...
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FatFs. How to find the end address and start address of a file on a USB drive?
USB drive connected to STM32F407VGT6
I need to find the end address and start address of text and ...
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Powering a passive usb hub with an external power supply? [closed]
So i have a generic usb hub with 4 ports, and as a usb 2.0 normally gives 5V at 500ma, could i just cut positive and negative and wire it to an external power source?
I tried it and pc won't recognise ...
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Charge USB C cable with no CC pin
I just want to make a "USB C" charging cable from 5V power supply (have cut cable w/ red black green and white pins connected from factory). I just want to use 500 mA max.
How do I connect ...
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STM32 USB Full Speed and card reading causes slow USB speed
I-m trying to accomplish best USB speed through STM32H743 MCU to PC.
First of all I was testing just receiving data. I was sending sending 8192 bytes from MCU to the pc without any other tasks, and ...
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USB 3.0 Debug Cable with a Type-A To Type-C Adapter
I know that the USB 3.0 Debug Cable is just a standard USB 3.0 without the 5V supply line (VBUS).
I have a USB 3.0 Debug Cable Type-A to Type-A (in particular this one: USB 3.0 Debug Cable).
I need to ...
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Capacitors on USB data lines for better USB data blocker
USB data blockers are small adapters that have a male and female USB connector, but inside the data lines are disconnected.
They can be used to safely charge your devices on public USB ports without ...
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Parallel MPPT and buck with PV to power an ESP32 via USB
I have a 100w 20v 5A PV that is being used to charge a 72v SLA pack. The MPPT has the 12v-60v input and output 24v-72v range I need. It doesn't have a USB port built in though.
I'd like to have this ...
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Can I override negotiated USB power requirement?
I have a Wacom CTL-472 tablet. On the back panel it says Input: 5V, 25ma. And if I use a USB power measuring device, it is actually less than that, drawing 19ma.
So I expected to be able to plug this ...
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Can any one help me in writing a code for just out put VCC = 5 V for 120 sec only when there is a trigger signal thee go off all the day? [duplicate]
The red and black colors in the USB Cable all time out put VCC = 5 V and Ground = 0 V , Can any one help me in writing a code for just out put VCC = 5 V for 120 sec only when there is a trigger signal ...
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Can anyone help me write a program in Python to output 5V from a USB port to control a relay? [closed]
Can anyone help me write a program in Python to output 5 V from a USB port for only 2 min and then off for feeding a relay using only the power wires of the USB cable and without using an Arduino?
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5V USB-Power without Battery makes MCP73832T toggle the LED
My schema works as long as the Battery is attached to it.
In fact, it even works if I disconnect the Battery - EXCEPT that the LED1 toggles in that case.
My intention is to use the circuit either
5V ...
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How can I make a USB cable use a push button & capacitor to allow power to flow?
I'm looking for a way to make a usb cable have a push button connected to allow power to flow.
'Device_X' should have a momentary button and, I'm assuming, a capacitor that gets charged when the ...
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Serial port (USB) status, powering off a peripheral device vs. unplugging it?
I asked this question yesterday on Stack Overflow. It may be a hardware question, and it may be a software question. The question is getting very few views in the original forum, so I am reposting ...
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USB peripheral not responding to SETUP packets
I'm writing some Verilog on a Spartan S7-50 FPGA to control a MAX3421E (datasheet) over SPI. I've gotten everything working with setting up the chip (full-duplex, Vbus, connection detection, host mode)...
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USB D± : Simultaneous BC 1.2 and USB2.0 data transmission Possible?
Background
USB pins D± are used for:
USB 2.0 data transmission
Battery charging (BC 1.2)
Question
Can D± be used for USB 2.0 data transmission and BC 1.2, or does BC 1.2 preclude the use of USB 2.0 ...
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SAMD51 can't get USB to enumerate
I made a simple custom board with a SAMD51 and am trying to get USB to enumerate on my computer, it works with Atmel START USB example so I know the board is ok. I have a problem where after sending ...
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USB-C: Adding Data Transmission to USB PD
Background
Texas Instruments' reference design PMP41013 exhibits bidirectional power transmission (DRP) via USB-C USB PD.
This is principally accomplished through an IC:
...
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Merging HDMI and USB to one cable
I have a project which includes a display which has a mini-HDMI input and a USB-output (D+ D- differential pair) for touch screen.
How can I combine those two into one cable to talk to my MCU? I'm ...
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USB Type C - only for powering my board
I want to use a USB type C cable only to power my board.
My board requires 5V input and max of 2A load.
I read that by default, the USB Type C cable can give an output of 5V & 3A.
So, I am ...
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USB-C: USB PD plus Data Transmission: Possible?
Background
Texas Instruments' reference design PMP41013 exhibits the use of bidirectional power transmission (DRP) via USB PD via USB-C.
This is principally accomplished through the use of two ICs:
<...
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USB protection from short circuits [closed]
I just bought the Hantek6022BE oscilloscope and realized (unfortunately too late) that it needs to connect two USBs to the computer to work.
I think it is because of a power issue (maybe 500 mA from a ...
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Advice on design of a Wind Turbine system
I am currently doing GDP at university. Our project is about creating a portable wind turbine which can be used to charge phones and batteries via USB output (5V). As mechanical engineers we don't ...
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I2C to USB converter with interrupt
I have a touch screen with I2C and interrupt output and I would like to connect this touch screen over a USB cable to a host controller.
I know that it is possible to transfer interrupts on the USB ...
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USB serial connection between Raspberry-pi and Android-phone
I have a Raspberry-pi-3-model-B and an Android phone device.
The connections are as follows:
My raspberry pi is connected to my laptop through USB (this is not the important part).
Also, from the ...
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USB series resistors
I have 2 questions:
The USB differential pair D+/D- are impedance-controlled 90 Ohm transmission line..
Why do I need to put a 22 Ohm series termination resistor in it?
Isn't that a discontinued ...
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USB to FTDI connection
I try to connect USB 2.0 to a FTDI FT2232HL. This is my first high speed layout.
I am planning to use 2-layer board 1.6 mm. I know that I have to keep 50 Ω Z0 and 90 Ω Zdiff. However with the 2-layer ...
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Did I map the correct pin leads from web cam to usb cable for use on Raspberry Pi?
I have two Dell Latitude E5440 and I pulled out the camera for both of them. Although both the cameras look to have the same form factor, I do notice the inscription between them are different. One ...
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FT232H on PCB Causing "USB device not recognized" Error on Windows
I have designed the following FT232H circuitry into a board on which I require a USB to I2C interface:
This circuit largely comes from the schematic for the UM232H eval kit (which I have and it works)...
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Why does this USB-C connection only work in one connector orientation?
I have a setup of devices connected as follows:
A B C
[laptop]<---<<--->[keyboard]
Where
<- is a ...
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Issue in integrating USB with SD card using STM32F4 [duplicate]
I am currently working on a project that involves integrating USB functionality for data transfer and data logging on an STM32F407VG micro-controller. Specifically, I want to log data files on an SD ...
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Odd USB Hub + USB to UART Behavior
I've condensensed several USB connections into 1 leveraging the FE1.1s. I built an eval board that tests this setup prior to implementing into the bigger project (see attached schematic).
The FE1.1s ...
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USB pin connection in ESP32 PCB schematic
I want to know about the VBUS pin connection of the USB connector. I have an ESP32-S3-DevKitM-1 board.
https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/hw-reference/esp32s3/user-guide-...
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CP2102N-QFN20 Overheats and Blows Board
I'm currently working with a custom board that uses the CP2102N-QFN20 connected to a USB-C female port and an MCU for UART. The device should be bus powered, and as far as I can tell, I've followed ...
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FT4232H Not Appearing
I am currently testing a custom PCB using an FT4232 chip. I have had this chip manufactured and am currently trying to get it to be recognized by my PC. I have it currently connected to a USB port ...
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Can I put 12 V LED lights into a USB to be plugged into a USB power bank?
I'm doing a project for school and I'm going to be making a 3D print nano gauntlet from end game. I want to put some LED lights into it but I'm just trying to figure out for easy access if I can hook ...
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Can someone explain USB ESD-protection on Nucleo 144?
On the STM32 Nucleo-144 eval board, there are 3 different ESD protection devices for the USB port:
U19 = USBLC6-2SC6
U21 = ESDA7P60-1U1M
U22 = ESDALC6V1-1U2
Source:
https://www.st.com/en/evaluation-...
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Is pin B5 (Vconn) connected to anything in a USB type-C legacy cable assembly?
The USB Type-C Cable and Connector Specification specifies (section 3.5) that in legacy cable assemblies (cables that have an non type-C plug on one end) the CC pin of the C plug (pin A5) must be ...
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Establishing communication between laptop and an oscilloscope [closed]
I am trying to establish a connection between this oscilloscope and my laptop using the USB port on the oscilloscope.
This is my code in Python:
...
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USB HUB for OTG
I have designed a custom board with Processor which is having a dedicated USB 2.0 OTG port. I want to convert it to 4 USB OTG ports. so I was thinking to use the USB 2.0 HUB with OTG support for 4 ...
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What is the communication protocol used by non-expansion card USB ports to communicate with CPU?
USB ports can come as expansion cards, like this:
Now obviously, since this is a PCIe USB card, the communication protocol used by this expansion card to communicate with CPU is PCIe.
But what about ...
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Detect if the device is connected to a USB 2.0 or a USB 3.0 port
Is there a way for a USB 2.0 Device to detect if it is connected to a USB 2.0 or USB 3.X host port? I need this to figure out the maximum current the device can safely take.
Some more details about ...
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Powering NX3DV42 switch with 5 V?
I plan to use the NX3DV42 switch from NXP to switch between SWD and USB pins in a nRF53-based design. The goal is to provide USB in a default setting and SWD in an advanced setting by using a switch ...
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Can you draw power from the ADUM4160 USB isolator
I am developing a USB powered medical device and I am thinking of using the ADUM4160 to isolate the USB from the device.
However, there is one thing i didn't understand about the device: does it ...
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