This is intended for RHEL 8 and RHEL 9 users impacted by the issue described in this support article: https://www.sealevel.com/support/how-to-resolve-communication-is
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What is EtherNet/IP?
Jun 1st 2024
EtherNet/IP is open-source and is managed and developed by the Open DeviceNet Vendors Association (ODVA), a tax-exempt business league that includes a wide variety of
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What is Modbus?
Jun 1st 2024
Modbus, initially developed in 1979, is one of the oldest, most widely used industrial communications protocols. Traditionally, Modbus was/is implemented using RS-232
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SeaMAC: ssiEncodingNone vs ssiEncodingNrz
Mar 25th 2024
Aren’t the ssiEncodingNone and ssiEncodingNrz clock encoding methods in SeaMAC the same? They are very similar, but the difference is that “None” t
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Sealevel’s 7203e does have onboard dip switches that would allow you to turn off the 102 Ohm resistor; the 120 Ohm resistor can be changed through dip
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Parity, Checksum, and Cyclic Redundancy Check (CRC)
Nov 1st 2022
Parity is actually an extra bit that’s added to every data word. It can detect a one bit error within that data or byte Checksum is a sum all of the c
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Raw Mode or Bit-Shift Mode
Oct 11th 2022
Raw mode is actually the simplest form of communication. The card takes every bit of data that’s received from the communication line, groups it into 8 bit bytes
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High-Level Data Link Control (HDLC) takes Synchronous Data Link Control (SDLC) one step further.HDLC defines the content of the control byte, allowing the transmitt
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Synchronous Data Link Control (SDLC)
Sep 13th 2022
Synchronous Data Link Control, also known as SDLC, is a protocol that can be used for talking between computers or between computer and a remote device.It’s very simp
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Bisynchronous communications
Aug 30th 2022
Bisynchronous communications have a 16-bit synchronization sequence at the beginning of the message. The rest of the message is formatted using characters like start
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Monosynchronus Communications
Aug 16th 2022
Monosync communications, as the name implies, has one sync character, 1 8-bit scene character.The problem with this is the fact that an 8-bit sequence can very easily
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Sync Serial Cards: 5104 vs 5102
Aug 3rd 2022
The 5104 is our highest speed sync card. For high-speed communications, it is the perfect solution. Unfortunately, if you’re using async mode it’s not necessarily our
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Asynchronous vs Isochronous Communications
Jul 20th 2022
Asynchronous communication is a timed communication standard. Each bit has a particular width and time that it needs to be stable. Isochronous communication does no
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Synchronous vs Asynchronous cards
Jul 5th 2022
There are three main differences between our async and sync cards. The first is cost. Our asynchronous cards are very cost competitive. Our synchronous cards are al
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What is synchronous communication?
Jun 24th 2022
Asynchronous communication is what everyone is used to. Every device you normally connect to a computer is going to be using asynchronous communication. It’s a time
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What is asynchronous communication?
Jun 9th 2022
The important thing with asynchronous communication is the fact that since it is time-based, the transmitter and the receiver both have to be very accurately timed
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If you want to send a letter to someone in Germany, the interface is the way that you decide to send the letter. The protocol is actually the content of the text that
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Why is my SeaLINK USB serial adapter or HazPAC 10 Rugged Panel PC (Part #H1400811) serial port not working in Linux?
Mar 9th 2022
If your serial port is not working in Linux, please reference this article to learn how to configure USB serial adapters in Linux. USB Serial AdaptersHazPAC 1
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