Questions tagged [port]
A port is a physical interface for a computing device to other devices. They are often realized as a single pin or a set of pins and can be operated in different modes.
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ATmega - reading PIN defined as PORT
What value reads the ATmega328 in case:
DDRA = 0xff;
PORTA = 0x00;
pin_state = PINA;
another words, what is state of PIN if I/O is defined as output PORT and all ...
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What is the reason that this RJ11 cable can't be connected to this socket? [closed]
I connect one end of this RJ11 to my router's WAN port, and I connect the other end of it to a 3-pin plug, and I connect that 3-pin plug to the phone jack, but when I try to connect the RJ11 cable to ...
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Error during analysis in AWR Microwave Office
How to fix this error, and what does it mean?
A port is off grid. All polygon edges with ports attached must be 'snapped' to the grid.
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Can a ESP32 and PCF8575 IO port Expander drive a IRLR7843 MOSFET directly with a 6A Load?
I posted earlier about using BUZ11 Mosfets in my project and driving them with a CA3081 NPN transistor array. But as I need 24 Mosfets, the circuit parts count is still too high.
I have researched ...
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Altium: Duplicated instances of sheet symbols to create single PCB room
I'm wondering if the following is possible in Altium: To make my schematic easier to follow, I want to break up my sheet symbols into several different ones in the top level schematic, while not ...
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What's the name of this video door eye wire connector? (port and connector)
I bought a video eye on Aliexpress. A wire with a connector comes from the peephole, and there is a port on the back of the screen.
What are their names? Is it some kind of USB or what is it?
UPD: I ...
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STM32 USB virtual port data sending problem
My project needs to extract sensor data from STM32, now my problem is this CDC_TRANSMIT_FS function can only send uint8_t data, I want to at least send uint16_t data or 32-bit float, how can I achieve ...
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I want to use a single switch for two pins
This is my microcontroller circuit, in which I'm using two switches. The first one is an ISP switch and the second one is a RESET switch.
Is there any way to use only one single switch for both ...
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STM32F103 USB CDC - device descriptor request failed
I'm working on a custom device which has to communicate with a PC over a virtual com port. I'm using STM32CubeIDE with code generated by the included STM32CubeMX. Here's a little information about my ...
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I2C Strange goings on
I am using a Teensy 4.0 and an MCP23016 Port Expander (only I2C device) on my PCB.
I have 4k7 pullups to 3V3 on SDA & SCK.
SCK track is 77.9 mm long, 0.254 wide.
SDA 64.3 mm long, 0.254 wide.
I ...
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Reverse engineering port on laser for rotary attachment
I have a Trotec Speedy 300. It has the ability to control a rotary attachment by plugging it into a 12 pin Molex port inside the printer. The attachment costs over $1500 plus shipping from the company ...
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OpenOCD stuck listening on ports
I have a fresh install of Maxims Micros SDK and I am having an issue when I try to debug or even run on target. I get the following output on the eclipse console, it never gets past this listening ...
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How to lessen emission of an enclosure box from I/O ports?
I am designing an enclosure box which will contain motor controllers(TB6600), microcontroller(ESP32 and Arduino Mega) and a 12 V power supply. I have not decided which material will enclose this. My ...
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Why do RF hybrid coupler opposite ports cancel?
I am reading "Practical Radio Frequency Test & Measurement A Technician's Handbook." by Joseph J. Carr. The book states on page 36 (screenshots are attached) that "The one general ...
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Arduino PORT manipulation analogRead()
I am trying to figure out on my Arduino UNO how to read analog input using port manipulation. I have found a lot of tutorials on how to do that for digitalRead / digitalWrite, but nothing with ...
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Short circuit USB port with multimeter
I've installed new car audio into my car. It works fine for a few months now.
There is a USB port on the car audio for charging. Before actually using it, I wanted to test if it is safe enough and ...
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How do I calculate the terminal-to-terminal resistance and capacitance from an impedance matrix?
If I have a circuit with \$N\$ ports (and therefore \$2N\$ terminals), how can I calculate the terminal-to-terminal resistance and capacitance from a given impedance matrix \$Z\$? We can assume a ...
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8-bit quasi-bidirectional I/O port
The schematic attached is from a very old device. It's using the microcontroller SAB 80535. According to the datasheet P5.7-P5.0 is an 8-bit quasi-bidirectional I/O port. There's a keyboard, a LCD and ...
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Reflection coefficient in a microwave amplifier
I have a question about the reflection coefficient in a microwave amplifier (two-port network), what is it and what is it based on?
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What is the difference between PTC and PORTC?
I am working on s32k144 controller in which I learnt how to configure pins as INPUT, while referring data sheet I got to know the base address GPIOC base address: 400F_F080h which is matching with ...
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How to connect a Microchip ENC28J60 to 3 port stand alone unmanaged switch chip with out using MCU
I have a working design running a Microchip PIC24 with TCP IP stack using the ENC28J60 chip. I am new to switching, and would like to add a second port for daisy chaining multiple devices without ...
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2 Ethernet jacks on a Device with ENC28J60 chip in with switch
I have an Ethernet device that works with Microchip's ENC28J60 chip perfectly. So if I want to connect a cable from a switch/controller, to device 1 (that has 2 RJ45 jacks), then have device 1 second ...
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What is the difference between a USB port and a USB receptacle?
The Wikipedia article USB hardware states:
Standard connectors
The type-A plug. This plug has an elongated rectangular cross-section, inserts into a type-A receptacle on a downstream port
on a USB ...
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Why 8051 microcontroller uses four different ports for I/O instead of using address bus and control signals
8051 has four ports for I/O .Therefore four peripherals can be connected to it at a time .
My question is why doesn't it use the address bus to activate a specific peripheral ...and then use the data ...
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Is it possible to use SIM7600 modem for both data and SMS simultaneously?
I am interested in using the SIM7600 module for designing a system with LTE communication. The module will be connected to the host system via USB.
I would like the host system's Linux to use PPP to ...
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Test to identify active source in electrical network
I have a black box of a N-port electrical network and I wanted to know whether inside this box is there any active source of energy (i.e battery) present or not, so is it possible to determine active ...
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Determine the z parameters of two port network
New to EE, and I was wondering if anyone could help me check what is wrong with my answer on this question.
$$\frac{V1-Vn}{4}+\frac{V2-Vn}{3}=\frac{Vn-4V1}{2}$$
$$Vn=\frac{-27}{13}V1-\frac{4}{13}V2 -...
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What is this port called? I want to guess it is for video
What is this port called?
If this is off topic, please direct me to the appropriate place for my question
Looks equal in thickness to micro, slightly more narrow resulting in a more squared shape.
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Do we need to send HSync, Vsync, HFP, VFP, HACTIVE in the Display port
On going through the display port specification, in the main stream packet structure I see only the pixels getting packed between blanking start and blanking end. Don't we need to send HFP, HBP, Hsync,...
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What is inter-lane skew insertion in display port
I am reading the display port specification facing some issue in understanding some terminology
1. What is inter lane clock skew
2. In the fig 2.8 what is bus steering ?
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Question regarding a charger modification for a Dell 3100 docking station
I'm quite new and inexperienced to this so I would appreciate any guidance I can get.
Given the quarantine situation I need to work from home more so I purchased a used D3100 docking station but with ...
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What exactly do D+ and D- on a USB connection do? [closed]
Of the four pins on the usb I know the power and the ground pins are used to supply power to a USB device. But the other two ...
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What does _SFR_IO8(0x04) do? AVR
I'm trying to write a program in assembly to toggle the on-board LED of the Arduino MEGA2560.
To do so I just have to indicate the direction of the pin (13 in this case which is PB7) as output and ...
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Is there a way to direct the data to a particular port for this scenario?
There is a PC program which reads ASCII data from serial port in real time and processes it. The thing is I'm not able to change the code. The program reads the incoming data where one can only set ...
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Options for replacing a broken charger when dealer no longer sells these [closed]
First post on this exchange, please do not delete it as a "request for shopping recommendation", this is close to, but not intended as one of those.
We have a Trimble DiNi 22 which runs fine, but we ...
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USB3/2 hub cascading (reverse hierarchy)
I want to implement multiple USB ports using one USB3.0 and one USB2.0 hub with four ports each.
The microprocessor I want to implement these ports for has just a single USB3.0 port left (of which the ...
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How to trigger a relay through a USB port?
I'm more a computer programmer than an electronic specialist so my question might seem simple to you.
I have a speaker and some other devices, I wanted to turn them off when TV is turned off, so I ...
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What type of printer port is this?
I just got a currency discriminator (Carnation CR1500) that can be connected to a receipt printer. There is a modular jack on the back of the machine, but I don't know what kind of cable it needs. It ...
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Characteristic Impedance of a port
I thought that the characteristic impedance was a parameter defined only for transmission lines. But now I have this question: is it defined also for a port? And, eventually, what does it represent ...
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Decoding Signals from an Unknown Port on Spectrometer
We have a Thermo-Nicolet Nexus 670 FT-IR Spectrophotometer, made in the USA around 2000. It was the work horse of the infrared spectroscopy community. The instrument sends out signals to a proprietary ...
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Impedance of the circuit between given points
I am trying to learn one and two port networks and the book introduced Determinants and minors to calculate the impedance of the circuit. Kindly see the following question:
I have managed to do the ...
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Directional Coupler Terminals
I have a basic question about directional couplers.
In this scheme each port is represented by one wire. What does it mean? The other terminal of each port is GND for all?
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Pic Programming - Nested Loops
I'm having some problem with my code and I can't get my two loops working properly. I'm new to C programming so I might have got the basic loop concepts wrong. I've got 10 LED lights connected to my ...
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Understanding Ports on DAC
So I am working with this DAC and I am trying to attach reference voltages and outputs, but I am confused.
Looking at this image of the board, what is the connection to VOUT ? How do I connect to ...
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low voltage pin in Keil (ARM) debuging?
I am going to work with one TFT LCD 2'8 (ILI9325 Driver) with STM32F103RE ARM MCU. So I have one example program in Mikroc for ARM ( Microelectronica Co), which is working good, you could download ...
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For given circuit, does the current "io" through the branch equal zero after short circuit ? [2-port network]
The circuit is;
simulate this circuit – Schematic created using CircuitLab
For given 2 port network, Im shorting V1 to solve for y22 and y12 and apply a current source at V2.[Y-Parameters]
...
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Determine Y-parameters for given circuit. [Used Nodal Analysis]
I am trying to solve this circuit for past 3 hours, no success, so I am posting here.
simulate this circuit – Schematic created using CircuitLab
I used nodal analysis, I will go over the ...
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Exercise about voltage thresholds of logical port
I don't understand how professor resolves this exercise!
I have two connected logical port and I want to calculate the time of transition from low to high for example.
In the solution, the minimum ...
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Two-port model of a BJT
In electronic books, the small signal model of a BJT is given as:
I've just studied two-port networks theory and, as an application, another book I'm reading shows this picture:
1st question: why do ...
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Should I use all the pins from 1 Port or few from each available (STM32)?
I am using a MCU from the ST, specifically from the STM32L1xx series. I want to connect 2 sensors, both of which will use the I2C protocol, 1 MicroSD card with SPI and 4 Interrupts. Is it a good ...
