Questions tagged [rs485]
EIA RS-485 is a serial communication standard using differential signaling.
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TTL to RS485 converter problems
I have designed a custom PCB that incorporates a circuit for an RS485 to TTL converter. Previously, I successfully used a module (https://protosupplies.com/product/scm-ttl-to-rs-485-interface-module/) ...
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rs485/modbus issue
I am trying to enable modbus RTU communication between 2 inverters.
Both are set up with unique IDs, 9600Hz, 1 stop bit, No parity bit.
I can communicate with 1 at a time, as shown below in the ...
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USB and RS485 on same lines for ESP32-S3
For an ESP32-S3 based PCB that I am developing, I would like to be able to share 1 connector for two different communication protocols.
USB connection directly to IO19 and IO20 of the ESP32-S3-wroom1
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ATTINY85-20SUR and serial communication
I am trying to use this chip ATtiny85 for serial communication. So my question is, would you recommend using it for serial communication, such as storing names, IDs, data, and last operations? Should ...
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Can you connect an RS-485 bus as a loop? (no terminators, cable ends joined)
I'm looking at using RS-485 to connect a bunch of sensors across a lengthy distance (approx 500 metres) however the location of the sensors means it would be suitable for connection as a loop.
By loop ...
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UART communications using CAN bus differential signalling
I need to interface with a device that talks UART, but with CAN bus signalling. Here's a picture where a tester (which I want to replicate) talked to that device:
While RS485 seems similar, the ...
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Help understanding RS485 circuit
Could someone help me understand this circuit? Like what is the purpose of the logic inverter, is it for switching direction automatically? And if so, how is it working?
For example on the TX1 line - ...
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RS485 to CAN converter
I want to design where a RS485 Device Sensor reads inputs and the information it reads and sends is converted to CAN (Arduino UNO R4 Minima with CAN built in, or ESP32 with CAN built in)
Is this ...
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Replacing MAX485ESA IC into a RS485 module but not working
I have been struggling a lot with a MAX485ESA IC I bought from aliexpress. What I want to do is replace the component from a rs485 module. For some reason they don´t work and I was wondering if anyone ...
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How to find out if RS485 interface has termination
We have a battery with built-in BMS and I am preparing a PCB that is supposed to talk to it. I need to decide whether I put 120 ohm standard end termination or 60 Ohm for 20cm short "bus".
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Noise during RS-485 operation
I have a switching step-down power supply SCM1301A, from which the entire circuit is powered, namely the microcontroller, op-amp, RS-485. I digitize the signal coming from the microwave module, having ...
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Why are there two wires connected to each terminal of the RS485 port in energy meters
I want to connect the energy meters of our clients to a gateway so that the gateway can communicate with the meters using Modbus. I have visited several electrical rooms that have gateways installed ...
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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 ...
