Setting Device Properties
84
VisualArchitect v1.1
CONFIDENTIAL AND PROPRIETARY. COPYRIGHT, AMX LLC, 2006
Ethernet 802.11b
- (also referred to as "802.11 High Rate" or "Wi-Fi") -- an extension to
802.11 that applies to wireless LANs and provides 11 Mbps transmission (with a fallback to
5.5, 2 and 1 Mbps) in the 2.4 GHz band. 802.11b uses only DSSS, and allows wireless
functionality comparable to Ethernet.
802.11 refers to a family of specifications developed by the IEEE for wireless LAN technology.
Ethernet 802.11g
- Also applies to wireless LANs, and provides 20+ Mbps in the 2.4 GHz
band.
RS-232/422/485
- Standard Serial (RS-232, RS-422 or RS-485) connection. Serial
connections have their own communication parameters, unrelated to Ethernet communication
parameters.
Device:Port:System (D:P:S)
A device is any hardware component that can be connected to the NetLinx bus. Each device must be
assigned a unique number to locate that device on the bus. The NetLinx programming language allows
numbers in the range 0-32,767. Device 0 refers to the local Master; numbers greater than 32,767 are
reserved.
NetLinx requires a Device:Port:System (D:P:S) specification. This D:P:S triplet can be expressed as a
series of constants, variables separated by colons, or a DEV structure. For example:
STRUCTURE DEV
{
INTEGER Number // Device number
INTEGER Port // Port on device
INTEGER System // System the device belongs to
}
The D:P:S notation is used to explicitly represent a device number, port and system. For example,
128:1:0 represents the first port on device 128 on this system. If the system and Port specifications are
omitted, (e.g. 128), system 0 (indicating this system) and port 1 (the first port) is assumed. Here's the
syntax:
NUMBER:PORT:SYSTEM
where:
NUMBER
: 16-bit integer represents the device number
PORT
: 16-bit integer represents the port number (in the range 1 through the number of ports
on the Controller or device)
SYSTEM
: 16-bit integer represents the system number (0 = this system)
DSSS
= Direct Sequence Spread Spectrum. DSSS is used in wireless local-area
network transmissions where a data signal at the sending station is combined with a
higher data rate bit sequence, or chipping code, that divides the user data according
to a spreading ratio. The chipping code is a redundant bit pattern for each bit that is
transmitted, which increases the signal's resistance to interference. If one or more
bits in the pattern are damaged during transmission, the original data can be
recovered due to the redundancy of the transmission.
All four Ethernet connection types share the same communication parameters.
