Questions tagged [rs232]
RS-232 is the electrical standard used on most serial ports. Note that this standard is a +/- 15 volt system and requires a FDMI converter to make it compatible with TTL logic levels.
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Powering a device from the RS485 lines
I have found multiple RS232 to RS485 converter dongles (from different brands, models, and makes) that do not need external power to operate.
Connect the RS232 DB9 on one side, and three wires for the ...
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RS232 Noise problem
I designed an stm32mp1 mpu based pcb. When I connect from the m4 core and send the uart message, everything is as it should be. However, when I start the first stage bootloader from the a7 core, a one-...
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RS232 isolated communication via MAX3250
I have a two diffrent boards. One of the board is send the SoC and other things to Charger Board. While charging progress starts I want to isolate this to device because battery ground is isolated to ...
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Split RS232 RX line on 3 interface
I have a device that sends data (telemetry) over an RS232 serial port. The RX line is not used, this device only sends one string every second.
I need to read this data from 3 different devices, each ...
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Why does RS-232 Communication fail between these 3 ESP32's?
What's the Goal?
Trying to get two esp32's to communicate over their UART lines using RS-232.
My initial inspiration and idea for the connections was based on
https://esp32io.com/tutorials/esp32-rs232
...
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Proximity sensor (3 Wire NPN or PNP) to RS-232
I do have 2 proximity sensors (level sensors) with 3 wire design. They offer to be PNP or NPN and I need to implement them into an RS-232. They are supplied by 24 VDC. Is there somewhat like a ...
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Convert RS232 signal to USB
I have an optical amplifier that uses RS232 and I want to convert to USB. I've purchased this chip, also here. There is little documentation on this chip and the supplier hasn't responded to questions....
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What do the different LED lights indicate on a DB-9 tester and what can I infer from them? [closed]
I have a machine with an RS-232 port. When I power ON the machine and connect the DB-9 tester all the machine's troubleshooting guide requires is to check if the RTS light is green. I see there are ...
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Could RS-232 data be carried over a standard 3.5mm audio/aux cable?
I am looking at RS-232 control for various TV displays which use a different type of input connector for RS-232. The combination of RS-232 inputs on different TV displays is the standard 9-pin DB9 ...
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Odd behavior using the MAX3323EEPE to translate RS232 output to TTL logic levels
simulate this circuit – Schematic created using CircuitLab
I am using the MAX3323EEPE Maxim IC in order to attempt to take RS-232 output from a peripheral and shift it down to TTL logic levels ...
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max3232 disconnection suddenly - problem
Hi I use a Max3232 chip to connect the RS232 between the microcontroller(STM32F103) and an HMI, the problem is that sometimes this connection will be disconnected and no longer work, this may happen ...
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STM32 UART without HAL library
I am writing register level code for STM32F4 & in my code there is a timer for calculation of the frequency of an input signal.
I am trying to implement a UART for sending calculated data to ...
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RS232 and RS485 sharing same wires
I'm planning a serial port that can either work as RS485 (half duplex mode) or as RS232 (configurable by the user).
There are several UART to RS232/485 chips around (like LTC2873), where a GPIO ...
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Can TCC-100/100I Series Industrial RS-232 to RS-422/485 converters with optional 2 kV isolation convert RS485 to RS232? [closed]
I want to convert RS485 to RS232 to connect it to a Moxa Nport 5610 - 16 port RS-232 Ethernet serial device server.
Can I use a TCC-100/100I Series Industrial RS-232 to RS-422/485 converter to convert ...
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Ethernet to UART (or RS232) conversion
For the PCB I'm designing, I need serial communication (1.8V UART, 3.3V UART, 5V UART or RS232, whichever is easiest) from an Ethernet connection (the devices connected to the Ethernet network will ...
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RS232 : dedicated signal ground or common with power ground?
I'm designing the PCB for a robot, where I plan to add some connectors for external RS232 tools (provided by the client).
Each connector will provide power (either 24 or 48V, at 5A max) and an RS232 ...
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Is it okay to call a UART “RS-232” if it doesn’t respect voltage levels specified in the RS-232 standard?
I have been using this converter call it converter A to communicate an MCU through its UART pins RX TX. And I wouldn't call this RS232 because RS232 is about physical layer and voltage levels as ...
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PIC16F UART Receives only the first byte
I'm currently working on a PIC16F18855, I'm trying to set up the communication part.
My setup is as follows:
A PCB connected to my computer via a TTL232 cable.
The PIC16F18855 is clocked at 32Mhz, the ...
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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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What to look for when selecting a cable for transmitting multiple types of signals in a moving environment
I'm working on a device that involves transmitting data between a microcontroller and an IMU device housed on a different PCB. The two are connected via a cable using a mini DIN connector. I've ...
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MAX3232 ESE+ Not Working but ST3232C and MAX3232 Working on same PCB
I have designed a pcb for Rs232 to TTL, UART converter for using ESP32. I will control an LCD with ESP32. Some IC's (MAX3232 ESE+) heating at the first start. and not working just heating and heating. ...
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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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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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Isolation on RS232 bus
Is there any "simple" way to get (1500V) galvanic isolation on RS232 (just RX and TX)? By isolating, I mean than I have 2 different grounds on each side of the insulation barrier.
On side A, ...
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Can RS-232 DB-9-compatible cable be used as a physical medium between two CAN bus DB-9 ports?
Note: I am not talking about connecting an RS-232 device to a CAN bus!
I am strictly interested in reusing a RS-232 cable with two DB-9 connectors (one male and one female) to connect two CAN devices, ...
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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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Modbus ASCII messages delimiter
I need to implement Modbus messages reception over UART. For RTU it's easy because UART on my uC has configurable idle receive line detection. However, for ASCII the task is tricky - the delimiter is ...
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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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Why does the data observed on a UART/RS232 bus look different between a logic analyzer and an STM32 Debugger?
I'm trying to communicate with a BNO055 using an STM32L552ZET6Q microcontroller via UART. The BNO055 is on a separate board, and connected to the STM32 via a 1.5M cable. Additionally, there are ...
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