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New answers tagged rs485

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RS-232 is single-ended, meaning that the signal is referenced to the ground, while RS-485 is differential - signal is referenced between A and B. That's before we even talk about TE/RE(DE) signalling of half-duplex. What you need is a signal converter between single-ended (UART/RS232) to differential to even start communicating. Whether you implement it ...

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RS485 networks should just have the 120 ohm terminations on each extreme end of the two wire bus. The RS485 bus driver is designed to handle the DC current flow for this pair of termination resistors. If you build a small network of 3, 4, or maybe even 5 devices the driver will typically have enough drive strength to handle terminations at every node. You ...

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Step 1) Get a serial terminal program (like realterm) Step 2) Set the device to your RS485 controller Step 3) Set the baud rate (the default for the temp controller is 19200 baud) Step 4) Set the stop bits and parity bits 8, N, 1 (8 bit, no parity, 1 stop) Step 5) EN26Parameter has the same meaning of cycle time for heating action .Parameter ...

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Here is what I have gathered here from the answers, comments, and some additional research: 1) The cable that shipped with the device should work for my purposes. However, I will need to be able to install the correct driver(s). Upon further research, I was able to figure out that the device manufacturer downloads include a Windows installer for this ...

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Is it necessary to do the ethernet cable splicing as indicated in the above link, or should I simply be able to use the provided USB cable? If you can find drivers for the R Pi then you can use the converter. I'd start by finding out what chip is in the propriety RS485 to USB, they might have a linux driver. Is it likely that the shipped cable is ...

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Managing with Profibus over decades as field engineer, I had never found some exotic solution. It's always used with DB9 connectors with termination switches or pass through for daisy chaining. By the way, Profibus max. speed is 12 MBaud, RS485 physical layer. The only weird part are PCB inductors, probably needed to limit $\dfrac{di}{dt}$ in case of ...

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Impedance is always defined by geometry of conductors and dielectric with respect to (wrt) each other (DM) and wrt power ground and/or earth ground. (CM). Saturn PCB design.exe. May tell you for a typ. Fibre/epoxy dielectric that 50 Ohms is somewhere between 0.5 to 1:1 diameter/gap and 120 Ohms is higher ratio. A track pair or short wire pair may be 1nH/...

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Yes, you do want to keep the trace impedance on the board as close to 120Ω as you can, mainly because this affects how the signal propagates on the cables attached to it. Presumably these devices are being daisy-chained together, and the reflections caused by impedance discontinuities will accumulate to reduce your overall signal integrity. There are ...

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With such a small distance and baud rate, the matching will probably not matter because the speed is low, reflections and parasitic effects will be minimal. Parasitic effects start to take hold when you get into the 10's of MHz. Because RS485 is differential, it does not need a ground plane, you could provide shielding if you like to minimize noise. You ...

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No problem going to 2f is = 50 Mbps. The probability of error depends solely on the Voltage becoming the wrong polarity when the discriminator has computed the polarity for that bit.. What affects the SNR? , that determines the BER. The slew rate indicates a variable amplitude and thus a variable SNR declining signal level, this also means a declining ...

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