Questions tagged [rs485]
EIA RS-485 is a serial communication standard using differential signaling.
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Puzzle how isolated RS-485 (ADM2582) sends signal without signal ground
Galvanically isolated RS-485 surely needs a signal ground, which leaves me puzzled about the following circuit -- which apparently sends the RS-485 signal correctly without the isolated grounds being ...
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What technology to use with multiple embedded systems talking to each other?
I am planning on building a system with one master and multiple slaves using MSP430 microcontrollers. The microcontrollers must talk with each other with serial interface using RS-485. I now need to ...
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How is SM712 TVS array suitable for use with MAX485 in an RS485 driver circuit?
I have an RS485 driver circuit consisting of a MAX485 driven by an STM microcontroller. I was looking at TVS diodes for basic protection from electrostatic surges from wiring and handling, and found ...
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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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How to connect RS-422 to 2× RS-485?
I want to connect two Arduinos via RS-422. I have 1 converter RS-422 to TTL and two RS-485 to TTL. How I can connect outputs of my converters (Y,Z,B,A on MAX490 and A,B on MAX485)?
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RS485 isolated or not for home automation system?
I'm creating a home automation system for condominiums. Practically there are a series of control units that communicate with remote sensors. Communication takes place via RS485 serial on an Ethernet ...
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Response partly lost in Modbus RTU over RS485 communication
I have developed a Modbus slave which uses ATMega8A and MAX485. In a new lot of the devices, while testing them on my PC using QModMaster, the response that I get has one byte in front of it, and cuts-...
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Can I use LED on the actual RS485 bus?
How bad of an idea is to put a LED on the actual RS485 bus AB lines, for indication of activity on the bus. Something like this:
I know people would say why not put LED on 'Recieve' and 'Drive' pins ...
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Pulling Receiver Enable Low for RS-485 Transceiver is being transmitted as a byte in Modbus packet
I am running into an issue where pulling RE low on my Max3441EESA is appearing as an extra byte in my Modbus message. I am currently testing the Modbus capability of my PIC32 MCU with a Modbus slave ...
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RS485 Wiring and Enables
I have an sensor with an RS485 interface that has a pinout with labels V, GND, A and B. In my system context, there will just be this one sensor and an ESP32 microcontroller running on 3.3V to ...
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Connecting a non-galvanic isolated RS-485
I would like to consult if I am designing RS-485 connection correctly without risk of damaging anything.
Main goal: I want to get data (e.g. flow temp) from Danfoss ECL 210 district heating control ...
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Is 74244 buffer suitable for multiplying data and enable in my Rasberry Pi3 to ATmega128A bidirectional communication?
My Raspberry sends data at baud rate 115200 to 300 remote panels (ATmega128A) through RS485 bus serial communication.
Also it sends enable signal (5 V) and receive feedback from the 300 panels at the ...
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How fast can a Schmitt trigger operate? Can I use it for signal conditioning digital serial data?
I would like to know if I could use a Schmitt trigger chip (e.g., 74HCT14, CD40106B and 74AC14) to clean a 12MHz serial digital signal that has gone through a long cable and will pass through multiple ...
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Potential Reasons for Fault on RS-485 Transceiver
I am working with the MAX3441 RS-485 transceiver, but I have run into faults with the three transceivers I have tested, so I am wondering if anyone can shed some insight on potential reasons for the ...