All Questions
172
questions
0
votes
2
answers
105
views
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
...
0
votes
1
answer
42
views
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 ...
0
votes
1
answer
138
views
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 ...
1
vote
3
answers
100
views
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 ...
0
votes
1
answer
540
views
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, ...
4
votes
2
answers
663
views
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 ...
0
votes
2
answers
203
views
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 ...
0
votes
1
answer
112
views
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 ...
1
vote
1
answer
275
views
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 ...
7
votes
3
answers
2k
views
Must RS-232 devices use the same logic level?
I want to interface a microcontroller with the RS-232 COM port of my PC.
My PC uses a 75232G IC, which uses +/-12V logic levels as per some multimeter tests.
Currently I'm planning to use the ...
2
votes
1
answer
183
views
On a (Windows) PC, can the TxD pin on COM1 be bitbanged? If not, why not?
In this question:
Why usb to serial port converter can’t program avr microcontroller?
Cornelius claims:
"DTR and RTS are the only pins of the serial port that can be bitbanged."
But is that ...
3
votes
1
answer
502
views
RS232 LED matrix programming
I managed to pick up two 16x64 unbranded LED matrix for next to nothing. My son has autism and absolutely loves LED scrolling signs so I thought it would be a nice project to build for him. They have ...
1
vote
1
answer
387
views
How does using an RS232 splitter affect the data transfer speed?
I am converting digital data into an analog signal through the RS232 PCIE card I added to my PC. I have a desire to collect data from up 8 different RS232 connections and I am looking into using an ...
1
vote
2
answers
1k
views
Is it possible to use an RS232-USB cable (with an FT232RL chip) for RS485-USB communication?
I have a standard RS232 to USB cable found on Amazon.
It does not work out of the box. This is what I expect since RS232 uses a ground reference and RS485 uses a differential between the two data ...
0
votes
1
answer
230
views
How is the output of this circuit RS232?
I'm trying to design a multi-channel USB-RS232 adaptor (inspired by this) to go into a larger design. After hunting a little, I found this schematic in the datasheet for FTDI's FT4232, which is the ...