All Questions
Tagged with rs485 communication
53
questions
0
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0
answers
51
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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 ...
- 11
1
vote
1
answer
67
views
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 ...
0
votes
1
answer
151
views
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-...
0
votes
2
answers
122
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Token Passing: Multi Master Protocol Initialising problem
I am into developing a protocol using Token Passing topology. For Physical Layer RS485 will be
used. All the nodes will be connected in a daisy chain. No node is initially known the address of
the ...
- 249
0
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0
answers
97
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Trouble to receive data from RS485 encoder in TM4C1294
I am trying to read data from an absolute RS485 encoder Single turn "eCoder-20S". The controller is EK-TM4C1294 launchpad. I am using SN75716AP for converting RS485 to UART conversion.
The ...
0
votes
1
answer
122
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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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-1
votes
1
answer
165
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PIC16f RS485 reception ok, transmitted data incorrect
I am currently working on a RS485 communication, I use a PIC16F18855 and a THDV1505.
I communicate with my computer using a USB/RS485 converter.
The PIC receives the data well, but I have a problem ...
- 41
2
votes
1
answer
844
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RS-485 4-wire to 2-wire converter
I'm looking for a way to be able to electrically switch between 4-wire and 2-wire RS-485. Up until now I have used jumper connections to establish both communication ways with one circuit. But I would ...
- 33
3
votes
1
answer
2k
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Different types of RS485 circuits
I've seen in some schematics that the RX, TX, RE and DE pins are connected to VCC with a resistor. This is how the connection with the UART pins is made (see schematic below).
In some schematics, ...
- 673
1
vote
1
answer
673
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Using CAN with Teensy 4.1 is better than using RS-485 which requires extra converter?
I am using Teensy 4.1 and need to communicate with motor driver which supports CAN and RS-485.
In teeny4.1 CAN is supported yet it requires CAN transceiver whereas if I want to use RS-485 I need to ...
- 525
3
votes
2
answers
653
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Connect multiple devices with USB
Consider a setup with 1 "server" device and 4 "client" devices (all are SBCs with Ubuntu installed). I would like to connect the 4 clients to the server, using USB/serial. Ethernet ...
- 151
0
votes
1
answer
194
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Can MAX485 be connected to SN75176 for RS485 communication?
In one side I have an SN75176 and the other side is MAX485. Can both be connected for RS485 communication?
- 427
3
votes
4
answers
8k
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Rs485 A & B Labels being used inconsistently
I would like to know if there is an official standard with regards to rs-485 terminals being labelled A & B.
I have always believed:
A=> + (positive)
and
B=> - (negative)
however, I have ...
- 213
0
votes
2
answers
186
views
RS485 Reverse Engineering
I'm reversing a RS485 comunication.
I have purchased a logical analyzer for reversing and sniffing the data packets.
But i have a problem, don't knowing the exactly comunication parameters i can't &...
1
vote
2
answers
953
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RS485 different voltages
Please note that I'm a beginner in electronic...
Hello, I've got myself some RS485 modules to test with Arduino and i managed to get them working in half-duplex.
From this post I've seen that for ...
- 33