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November 2008 - Issue 11 Vol. 7

Test your knowledge with Tom’s monthly trivia question.
Who was the Cook County Assessor’s office clerk in "The Blues Brothers?"

Click here if button does not work

First 10 correct responses
win Sealevel stuff.

What soon to be famous Guitarist backed Boz Scaggs in the studio
back in 1968?

Duane Allman


Suffering from USB disconnection?

Depend On Any of Our 35+ USB Serial Adapters
USB serial adapters

Sealevel offers over 35 different USB serial adapters - more than any other vendor. With the benefits of Sealevel USB serial adapters, you can:

  • Eliminate the single most common point of failure when using USB industrial I/O devices - accidental cable disconnection. Our innovative SeaLATCH® locking USB cables and connectors will ensure that your USB connections are always secure. SeaLATCH connectors are fully compatible with standard USB cables.
  • Free yourself from the aggravation of opening enclosures to change jumper settings or dipswitches with our latest software configurable USB serial adapters. Each port is individually configurable for RS-232, RS-422, or RS-485. Interface settings are maintained locally allowing the host computer to be upgraded or replaced without reconfiguring serial ports.
  • Drive up to 16 serial ports at maximum data rates with Sealevel’s “dedicated USB UART” design. Our architecture significantly increases the performance of multi-port USB serial adapters by allowing all ports to operate error-free at maximum speeds.
Sealevel USB serial adapters are available in extended temperature ranges and OEM versions without enclosures. Our products are backed by a Lifetime Warranty, industry-leading technical support, and rapid design services for custom applications. View our USB serial adapters or call us today to discuss your specific project requirements!

Tech Lowdown – Do I need to connect a ground line using RS-422/485 communications?

Do I need to connect a ground line using RS-422/485 communications?The short answer is yes. Differential serial communications such as RS-422 and RS-485 use the ground as a reference. If there is no ground, the reference is basically floating. Electrically, it will work unless the floating reference causes the data line voltage to exceed the common mode range of the transmitter/receiver. If you have devices on different power circuits there is a high probability of ground differences that can lead to communication failures when a ground line is not used. Learn More

USB DB9 Serial Interface Adapter

USB DB9 Serial Interface Adapter
The SeaLINK® 2223 is an easy way to connect to serial devices to a single USB port.

  • Software configurable for RS-232, RS-422, and RS-485
  • Electrical interface settings maintained locally
  • Supports data rates to 921.6K bps
PC/104 High-speed Synchronous Serial Interface

PC/104 High-speed Synchronous Serial Interface
The 3512 high-speed serial interface module is configurable for RS-232, RS-422, RS-485, RS-530, RS-530A, or V.35.

  • Z85230 Enhanced Serial Communications Controller (ESCC™)
  • Various oscillators available for custom clock rates
  • Selectable port address, IRQ level and DMA channels
Ethernet Asynchronous Serial Server

Ethernet Asynchronous Serial Server
Connect a single RS-232, RS-422, or RS-485 serial port to your Ethernet network with the 4103.

  • Serial ports appear as virtual COM ports to the host machine
  • Serial port is optically isolated
  • Includes Reed relay output and optically isolated input
HMI with TFT LCD and Resistive Touchscreen

HMI with TFT LCD and Resistive Touchscreen
The S1200-17R combines Sealevel's Relio R1200 embedded computer with a large, bright 17" TFT LCD and resistive touchscreen.

  • 1.0GHz ULV Intel Celeron M CPU
  • Operates from CompactFlash for solid-state operation
  • Supports Windows Embedded and Linux operating systems
Wireless 802.11b/g Modbus TCP Digital I/O

Wireless 802.11b/g Modbus TCP Digital I/O
The SeaI/O 520W provides eight optically isolated inputs and eight SPDT high-current Form C relay outputs.

  • Complies with 802.11b and 802.11g (2.4GHz) wireless networking standards
  • Security features include WEP and the latest WPA-TKIP and WPA2-AES encryption standards
  • I/O expandable with SeaI/O "N" Series modules
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Visit for synchronous or asynchronous serial, analog or digital I/O, industrial computers or touchscreen HMI systems.