Questions tagged [serial]
In serial communication data is transmitted as a sequence in time. Main advantage: much less wires needed. Main disadvantage: Higher bandwidth for the same throughput.
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Serial USB and battery charger in an ESP32-based PCB
I'm developing an ESP32-based board with a USB used for both firmware upload through serial and 3.7v LiPo battery charging. Although, I'm not sure if I've developed these parts well.
I share my ...
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MAX3362 RS485 IC connection with ESP32
I am using MAX3362 RS485 serial data transfer IC with ESP32. Marked pins 1, 2 and 3 are connected to GPIOs of ESP32. Do I need to add any additional pull-up resistors or some termination resistors or ...
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DTR pin in the FT232RL working confusion
I have seen one of the schematics of the Arduino Nano where I have the DTR pin of the FT232RL connected to the capacitor and then to the reset of the Arduino. As far as I have understood, when the USB ...
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How were standard serial port baud rates chosen?
How were standard serial port baud rates chosen? 1200, 9600, 115200, aren't the numbers we'd expect (powers of 2 or 10), but don't seem random either.
Wikipedia states
Many of these standard modem ...
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Strange serial comms where data sent has missing characters using Arduino UART
I have an Arduino Uno that sends data to the Raspberry Pi over UART.
But a lot of the time, I am finding that some of the data is missing.
For example, it supposed to send:
...
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How should I debug this ARM Cortex M STM32 UART write?
I have a STM32F446RE on a Nucleo F446RE, and I'm trying to learn how to program the UART to write over the Virtual COM Port (connected to USART2).
I'm able to download someone else's code, modify it ...
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How can I find which serial port is connected to Nucleo board via ST-LINK?
I have a Nucleo board connected via USB to ST-Link running on Ubuntu Linux. ST-Link works well in that it can program the board. I would like to use the built in virtual serial port, but am not sure ...
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USB Type-C pins' designation
I am trying to design a USB to Serial converter featuring CH340C IC and I'm a bit concerned whether I have correctly hooked up the SBU, DP/DN, and Shell pins. Is there any chance that I did everything ...
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Difference between DM13A and TLC59281 Constant Current LED sink Drivers
I was using DM13A driver in my old PCB designs and it was working perfectly using Arduino Mega. Due to parts shortage at JLCPCB I had to use TLC59281 driver for my new PCB. But TLC59281 is not working ...
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How to set up RS232 UART in Proteus?
I am having difficulties sending the correct message to the hyper terminal from ATmega32 micro controller. For some reason, the MAX232 chip is giving undesirable voltage levels. I want it to give ±15 ...
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USB Port Design with ESD/Overcurrent Protection
I am working on a small project in which I use a CH340 to communicate with an MCU, but during prototyping I probably should have a way to protect the controlling computer's USB port from shorts. I ...
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Placement of USB/UART converter for robustness and noise immunity: long USB cable or long EIA-422 cable
Consider the very common case of communication between the UART peripheral of a microcontroller and a PC, using a USB-UART converter such as are available from FTDI and others[1].
If there's a non-...
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If there's no ADC and DAC in SerDes, how come the signal that passes through the channel are analog signals?
On the Tx side and the Rx side, the signals are digital. And the way we determine whether a SerDes is good or not is to check its eye-diagram, which means there's no analog signal appearing in the ...
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Baud Rate calculation from logic analyzer
I am somewhat new to approaching this from this angle, been using serial coms as documented for many many years configuring everything from radios to network equipment. Familiar with what baud rate IS ...
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How to prevent power transfer (reverse current) between two DE-9 RS-232 cables? [closed]
we have two USB host devices that communicate with each other and as part of the chain, we are using two Serial to USB cables to connect them, like this:
We are not 100% sure as this happened at a ...
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ESP32-S3: Serial stops working after a random period of time
I am using a ESP32-S3 Dev Kit (Arduino code) connected to a MAX3232 to read data from a solar inverter. I am facing a strange problem as follows:
The UART (Serial1, ...
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Determining a serial protocol of an industrial crane
I'm currently trying to read packets sent between a small truck-mounted crane's controller (handheld device with joysticks/buttons/etc) and its control box. The communication occurs over a single data ...
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Serial communication baud rate issue
I am a bit confused regarding the baud rate of serial communication.
Suppose I am sending a value of 198 to the receiver with a baud rate of 9600. At the receiver, the rate is also the same. Thus isn'...
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UART isolation with opto-coupler
I've got two devices running on different power sources and different grounds.
I'd like to connect them together through a Serial connection (UART TTL) at baud rate 460800.
Both devices have 3.3V UART ...
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Serial isolation with 6N137 opto-coupler
I have two Raspberry Pi that I'd like to connect together through a serial interface.
I've spotted the 6N137-L which can work with 3-5 V input voltage. I can connect it to the 3.3 V or 5 V GPIO pins ...
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Can the effective transmission rate from a python script to an arduino be increased when using serial communication?
I attempting to move a servo (controlled by an Arduino) with a Python script. The Python script issues a command to the Arduino to tell it where to move the servo head to. The communication is handled ...
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How many UART interfaces can be used in this MCU
I want to understand how many UART interfaces can I use in this ATSAMD21 MCU.
I searched for "UART" in the datasheet to find which pins and how many UART interfaces I can connect to. But I ...
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Does it matter when I step down the voltage in a two part conversion?
I’m designing a 3.3V board using 328P that I want to program via usb, meaning I need a usb to serial conversion. My question is, does it matter if I regulate the voltage (MIC5129 LDO) between the USB ...
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Sampling 24V one wire serial with a voltage divider?
I would like to sample 24V one wire serial with a voltage divider, wouldn't grounding the resistors in series potentially affect the data being transmitted?
I was considering using an optocoupler but ...
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I need a microcontroller with two hardware USART ports [closed]
I have a rather peculiar requirement for a project:
I need some sort of microcontroller that has two independent USART interfaces that have to be reconfigurable at runtime.
Let's call them ...
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Not reading the start signal from DHT22 sensor
I'm trying to implement a program from scratch to read from a DHT22 sensor connected to an ESP-01 as a learning exercise. I am basing my implementation on the from adafruit DHT library. Following is ...
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When designing a product that uses a DE9 connector, is it normal to just classify it as an RS-232?
Question:
When designing a product that uses a DE9 connector, is it normal to just classify it as an RS-232?
Background:
I am seeing a lot of references to RS-232 while reading engineering documents ...
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ESP32 BLE Bluetooth Serial to Hardware Serial Bridge
I'm looking for a way to use serial devices with my iOS iPhone without buying a $20 device.
I have an ESP32 which can do Bluetooth Serial to Serial using this code but if I replace the Serial with <...
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I2C issue communicating with an analog to digital converter mux ADS1015 through TCA9548A I2C multiplexor
I am using a Raspberry Pi Zero 2 to talk through a TCA9548A to multiple ADS1015, each ADS1015 is on a separate SDA/SCL channel of the TCA9548A. I am able to scan all channels and see the active ...
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Decoding Pin Configuration and Compatibility of a Mouse Operating in RS-422 Half-Duplex Mode
I have come across a system whose keyboard/mouse input claims to work on RS-422 but it has only four pins instead of the usual five pins associated with RS-422. I am seeking clarification on the pin ...
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Interfacing TLC59731 with Attiny85
Has anyone had any experience communicating with a TLC59731 from an Attiny85? I'm not sure how to configure the USI to support the EasySet "protocol" described in the datasheet. I imagine I ...
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Detecting a break condition over UART on ATmega328P
I'm implementing a protocol which begins with an 88 µs break (low) and uses an 8-N-1 configuration.
The latter is easily set with UCSRnC, but is there a way to configure the UART hardware to detect ...
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Can I Use RS232 Library For RS422 in PIC Microcontroller?
I have this project where I have to use RS422 and Max485 serial communication.
The task is simple: The input from 15 buttons should be send to PC by RS422 using PIC18F4620.
I have no experience in ...
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Analyzing the complexity of a number in the Arduino IDE
I'm working on a project where I'm linking a calculator (TI-84) to an Arduino (Nano) and I want some way of classifying or quantifying how complex a single number is (small whole numbers being very ...
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ESP32 program completely halts when serial terminal is disconnected
My platform is ESP32-wroom (Devkit v1 board). ESP-IDF 5.0 on Win10.
I've been using PuTTY to monitor the ESP32's serial log and output (the main serial where all the diagnostic info goes, not the ...
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How to double a single TTL to link to 2 independent TTL terminal
I am working on a project that needs multiple serial connection between mcu sensors .
In order to send data by ttl serial from 1 mcu to 2 other mcu and reverse...
What is the best way to achieve this ...
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Attiny85 USIDR Write Speed
The USIDR register for serial communication on the Attiny85 is 8-bit. If I need to send 32-bits, can I write each byte sequentially as fast as the program can run, or do I need to delay between each ...
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Spikes in the signals acquired by Data Acquisition System
I am trying to develop a Data Acquisition System (DAQ) to monitor two analog signals. I am using Cy8ckit-059 development board as ADC.
After converting the analog signals to digital, I am transmitting ...
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Ublox Neo M8N + wemos lolin32 serial monitor problem
So i have a neo m8n that should print my lat and lon to the serial monitor,but fails to do so. Here is the code:
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Passing Serial Object Created by a Library to another Library
I am trying to create a library for Topway brand LCD based on this docs. Inspired by this library header file, and source file I have created a Serial object in my library which is fix.h and fix.cpp. ...
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Interfacing an old spectrometer with PySerial
I asked this question on the Engineering StackExchange and someone said it might be more appropriate here.
I want to interface an old Shimadzu spectrophotometer (Model UV-1601, manual here) through ...
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How to choose pull-up resistor values for level shifting circuitry for serial communications
I recently joined a new project where two ESP32-WROOM-32UE modules on separate circuit boards talk to each other via the UART pins. The distance between the two boards is roughly 1 meter of cable ...
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Reason to have MSB in a serial communication always high
I'm working on a code (written by other people) that uses a custom protocol to transmit data over RS485 in 8-bit packets.
For some reason, the protocol is built so that every 8 bits transmitted are ...
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Is there a way to use any communication without a CPU?
I am looking for a way to communicate without using a CPU on one side of the communication.
For more details, I have many cards that need to communicate with one main card on which there is a CPU. ...
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Definitions of Serial TTL UART MCU acronyms
I was looking for a comprehensive list of terms and acronyms concerning serial peripheral communication including their descriptions and, crucially, how they relate to each other. Since this site ...
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Unable to clear faults on Monoblock via RS232 command: Need help decoding serial messages with Arduino
I recently purchased an XRB160PN192 Monoblock with a known fault of high voltage (HV) for a low price to use in my graduation project. After reading the user manual, I found that the HV error, along ...
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RS232 DCD over Serial-USB Adapter
I've been reading about PPS in linux and GPS synchronization.
I stumbled on some sources recommending using a USB GPS, I'm nto quite sure I understand how the interrupt signal is passed through.
The ...
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How to make an ESP32 S2 not lose USB connection after uploading?
I am using an ESP32 S2 Mini, and I'm running into this problem:
I put the unit into the "flash" state, by pressing the "0" and "RST" buttons. Doing this establishes the ...
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Most probable cause for unwanted capacitance on serial line?
I'm a PCB rookie and just got the first sample of a 4 layer flex-rigid board that I made.
I'm using 3.3V TTL-UART @ 115200 baud, the stackup is as follows:
CU 35 (signal)
Prepreg 0.7mm
CU 35µm (GND)
...
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