CYB-LAN/2 Prototyping Board for Local Area Network Communications

Standard Features

• Communicates with the host computer over a standard three-wire RS-232 interface.
• Can operate at standard baud rates between 300 and 19,200 baud and non-standard up to 57,600 baud.
• One LED indicates when the 5V power supply is on.
• Accepts commands from and responds to your RS-232-C computer or CRT.
• Includes 2 CY233 Network Controllers.
• UP to 255 serial Nodes may reside on LAN.
• Easy Serial Interface with on-board line drivers/receivers, and triple RJ-11 Jack or Serial in, out, and Local.
• Includes address decoding logic for Local Node.
• CY233 Operating Modes are Jumper Selectable.
• 53 mm x 88 mm (approx. 2,1" x 3.5").
• Power requirements:
• Board voltage: +5V (55 mA max). RS-232 voltages are generated internally.

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CYB-LAN/2 Overview

The CY233 Network Controller IC has a special operating mode that allows it to be used for Local Area Network (LAN) communications, permitting serial devices, usually computer systems, to be connected in a network using only their standard serial ports. This special LAN mode is implemented on the CYB-LAN/2 board. It requires two CY233 chips per LAN node. The first acts as a network communications device, handling traffic between itself and other nodes of the network. The second, known as the local CY233, accepts message data in parallel from the Network CY233, and sends this in serial form to the local serial device.

Building a local area network from CY233s is a very cost effective way to connect several computer systems together. Although it will not have the same performance as an expensive, high-end network where large amounts of information are shared on a constant basis, a CY233-based design could work quite well for a network that requires occasional communications between systems at rates up to 19.2K baud. The CYB-LAN/2 is supplied in kit form with all necessary hardware to assemble a working board. Just add the cables and power supply.

Host Ring LAN

A number of CY233s are connected to the serial interface of the host.

Peer Ring LAN

All the local serial devices communicate with each other and no longer require a host controller.