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 throug
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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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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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My Ethernet Serial Server is missing from the SeaLINK Device Discovery utility. How do I find it?
Feb 2nd 2022
The most common solution is to disable all network adapters except for the one connected to the Ethernet Serial server, then try searching for the Ethernet Serial ser
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How to resolve communication issues affecting Sealevel’s XR17V35X based serial devices (7xxxec serial cards, 7106e, Relio R1)?
Aug 19th 2020
The following devices are based on the XR17V35X and are known to be impacted by the GPIO configuration issue described in this article:7xxxec serial cards7106eRelio R
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Using Sealevel’s COM Port Manager utility provided with our SeaCOM software suite, a PCI or PCIe serial port can be named “COM1.” After that
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A serial tunnel is formed by two Ethernet serial servers that transmit data received by the local serial port through a TCP/IP connection out through the rem
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RFC 2217 is a popular protocol for accessing serial ports over a network. A server that uses RFC 2217 allows its serial port to be controlled through the n
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What is Slew Rate Limiting and when should I use it?
Apr 13th 2016
Slew rate is a measurement of how fast the signal voltage changes over a specified period of time. At high data rates, you need a fast slew rate to ensure that the
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What is the ‘Gen Mod’ that Sealevel recommended?
Jul 15th 2015
‘Gen Mod’ is an abbreviation of ‘Generic Modification’ and it ensures that the COM port assignments on a USB serial adapter are alw
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How can I guarantee that different USB serial adapters will use the same COM port assignments?
Apr 30th 2012
When you connect a USB serial adapter to a computer, the operating system assigns individual COM port numbers to each serial port. Each USB serial adapte
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Most Sealevel serial adapters use the serial drivers built into the Linux kernel. For USB and UART-based serial adapters, the Linux drivers may need additional i
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Linux supports the direct use of 16XXX UART-based devices with the drivers included in the kernel sources. However, kernel versions prior to 3.7.0-rc6 are missing
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How to configure USB serial adapters in Linux
Dec 23rd 2011
The serial USB driver in Linux contains many product IDs for Sealevel devices. However, the newest devices may not be currently included in the driver. This g
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The 2107 is designed for two-wire (half duplex) RS-485 applications and provides reduced wiring costs and protection against EMI and other induced line noise
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Microsoft Windows maintains the configuration (enumeration) information for every USB device that has ever been connected, unless you explicitly uninstalled th
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Sealevel SeaLINK Ethernet serial servers support a 2-byte format to marshal 9-bit serial data between the host computer and the serial server. The least signif
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How do SeaLINK Ethernet serial servers transmit modem control signals in serial tunneling mode?
Jul 30th 2011
SeaLINK Ethernet serial servers use RFC-2217, the Telnet COM port control protocol, to transmit modem control signals in serial tunneling mode. Since S
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