Questions tagged [rs485]
EIA RS-485 is a serial communication standard using differential signaling.
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How is this RS485 Module Working?
I am planning to use this UART-to-RS485 module :-
http://www.elecrow.com/uart-ttl-to-rs485-twoway-converter-p-1545.html.
This module is bidirectional and uses a single pair of differential signal to ...
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Is CAT5 cable good enough for RS-485 vs "true" RS-485 cable
I have a serial comms project coming up. A number of boards with RS-485 interfaces need to communicate. Date rate is 57600bps and cable length will be less than a few hundred feet.
Will shielded ...
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Raspberry PI's SPI over RS485
I'm trying to understand how to connect a SPI device (a mifare RC522 RFID board) over long distance to my RPi via SPI.
I searched and find I could connect those via SPI over RS485 using a MAX490.
(...
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RS232 hotplugging
I've noticed that when I connect/disconnect the RS232 cable to my micro-controller, I receive a garbage character at the other end (my pc).
Is there a way to prevent this?
I want to eventually move ...
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RS485 network ground pin - when to connect?
As many know, one can implement a simple node to node rs485 communication by using only two wires, A and B. Well, the standard specify to connect the ground of the two node together.
from Wikipedia:
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J1708 Half Duplex Collision Detection
SAE J1708 is basically an RS485 hardware interface without the typical 120 ohm termination resistors. In typical applications, a half-duplex RS485 transceiver chip is used to connect to the bus.
In ...
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Transmitting VCC and GND signals for use with RS-485
The specific question I want to ask is whether I can transmit VCC(5VDC) and GND power signals for powering the destination circuit (in an RS-485 arrangement) or not.
The power lines will be grouped ...
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No response from device when using rs485
I've been stuck on this issue for quite some time. I am trying to use an arduino to communicate with another device using RS485. The problem is that I can see the data being sent but, the device does ...
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DMX on Arduino with RS485
I'm implementing DMX on Arduino. DMX uses the RS485 standard to communicate.
In the specifications of RS485 it notes that there is a positive line, a negative line and a ground line. If the positive ...
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SPI over long distance
I want to connect chips that use SPI protocol to communicate (To be specific those chips are ws2801) the distance may reach 100 meters.
How can I solve this issue? After a few days of searching I'...
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Decoding an unknown serial bitstream that does not fit 8-N-1
I am looking at an RS-485 signal using a scope and an analyzer (saleae). This is running a mystery bus (see below for more information). I would like to know how to fix my frame errors. I can't begin ...
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Can RS485 be considered a multi-master bus?
There are some electrical specifications specifically designed for multi-master protocols such as CAN, I2C, 1-Wire, etc. which are classified under CSMA/CD networks.
However, RS485 has a push pull ...
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RS-422 distance sensor with arduino
I need to make a converter to go from RS422 full duplex to my Arduino. I have found lots of different chips which I think can do this, but am slightly confused by the terminology. The RS422 device is ...
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Different RS485 Full-Duplex with RS422 [closed]
Are RS485 Full-Duplex interface same with RS422 interface?
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Can I an RS422 interface to Arduino's serial pins?
I have a custom-designed circuit that communicates to and from the external world through an RS422 interface. I wish to communicate with it with an Arduino, preferably UNO. The RS422, much like the ...
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