Black Box 485 - Manual (Page 2)

2 of 3 9/4/2007
#10133 724-746-5500 blackbox.com
FEATURES
• Poll “dumb” RS-232 devices on your
multidrop RS-485 line.
• Place your RS-232 devices up to 5000 ft.
(1524 m) from each other.
• 253 addresses for each network.
• Send commands to individual
SmartNode 485s or broadcast messages
over the entire network.
• No need to modify your RS-232 device
or your RS-485 line.
Add RS-232 devices to your RS-485 environment or create an RS-232 multidrop network.
OVERVIEW
SmartNode 485 is the first device to allow async RS-232
printers, terminals, scales, lathes, bar code readers—
any “dumb” RS-232 device—to function in a multidrop
RS-485 network.
An RS-485 network consists of a master device polling
slaving devices for information. RS-485 devices already
have the “smarts” needed to follow the rules for orderly
communication. In contrast, RS-232 devices are “dumb”—
unaided, they can’t follow the rules of a multipoint protocol.
And that’s where SmartNode 485 comes in.
SmartNode 485 does two jobs. It converts your RS-232
signals to the RS-485 interface so your async ASCII devices
can operate in an RS-485 polled environment.
It also acts as the address node for your RS-232 device,
allowing it to communicate with a master device on a
multidrop network.
SmartNode 485 lets you combine the variety of RS-232
devices with the advantages of RS-485. For example, the
superb noise immunity of RS-485 enables your RS-232 devices
to send data at rates up to 38.4 kbps, while residing on the
network up to 5000 ft. (1524 m) away from one another.
And SmartNode 485 does not require you to modify your
RS-232 device. Instead, you configure SmartNode 485 for
your device’s requirements through internal DIP switches.
Each RS-485 network segment can consist of 32 devices.
And up to 253 device addresses are available to SmartNode
485s on a network. Using repeaters, your SmartNode 485
network can be as complex as your application demands.
SmartNode 485 is available in either standalone or
rackmount card versions. A 230-VAC model is also available.
TYPICAL APPLICATIONS
Add RS-232 devices to your existing RS-485 network. Your
unmodified RS-232 devices operate along side your RS-485
machines.
Create a multidrop network of RS-232 devices. Place RS-
232 printers, terminals, and bar code readers up to 5000 ft.
(1524 m) apart. Control them with an RS-232 host controlling
the network via an RS-232÷RS-485 Interface Converter.
SmartNode
485 Logic
controller
Conveyor Lathe
Master PCs
Terminal
Printer
Scale
Bar-code reader
Terminal
RS-232 ↔RS-422/
485 Interface
Converter
Printer
Industrial controller RS-232 pump
SmartNode
485
SmartNode
485
SmartNode
485
SmartNode
485
SmartNode
485