CYCLONE-User-Manual.pdf - 第113页
User Manual For Cyclone LC Programmers 113 device to match those of the network. 10.4.2 Connecting Cyclone-to-PC via an Ethernet cable In order to connect the Cyclone to a PC directly via an Ethernet cable, you need to u…
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10.3 Internet Protocol
Once the network has been established, and the IP numbers have been assigned, data can be
transacted over a network with one of several protocols. By far the most prevalent protocol is the
Transmission Control Protocol (TCP), which runs on top of the Internet Protocol in what is
collectively known as the TCP/IP protocol. The TCP/IP protocol was developed by the Department
of Defense to connect different computers from different vendors by a “network of networks,” which
has become what is known as the Internet today.
The primary purpose of the TCP/IP protocol was to prevent a complete network outage in the case
of a nuclear attack, by automatically rerouting data traffic through the functioning part of the
network. As such, the TCP/IP mechanism guaranteed delivery of data packets by introducing a
system of acknowledgments and sequence numbers for the data packets. This mechanism, while
good for transacting large amounts of data (such as email or file transfers), is unsuitable in the
real-time type environment in which the Cyclone operates. Because the Cyclone needs to transact
data as quickly as possible to the target, it takes advantage of TCP/IP’s alternative, the UDP/IP
protocol.
Unlike TCP/IP, the UDP/IP protocol is a connectionless, single-packet protocol that sends short
data packets at the expense of not guaranteeing their delivery. This makes the UDP/IP protocol
efficient in real-time applications such as broadcasting video over the Internet, where the
occasional loss of a frame of data is not going to hamper the overall viewing experience. Left
unmodified, the UDP/IP, with its lack of guarantees for packet delivery, would be unusable in an
environment where the delivery of a single byte of data needs to be guaranteed. The Cyclone
firmware adds mechanisms to the UDP/IP protocol, without affecting its underlying efficiency, to
guarantee delivery of data packets.
10.4 Connecting The Cyclone Device
There are two methods for establishing a connection between a Cyclone and a PC with an
Ethernet cable. The most basic method is to connect the Cyclone directly to a PC, via a cross-over
Ethernet cable. However, the more common method is to place the Cyclone and the PC on the
same network through a Hub.
10.4.1 Connecting the Cyclone to the PC over a network
The Cyclone was intended for use on a network of multiple computers (and other Cyclones). There
are many possible network configurations, and to describe them all is beyond the scope of this
document. However, most configurations are a modification of a basic theme, which is that of
connecting one or more PCs through a Hub to one or more Cyclones.
In order to connect these devices to the Hub, you will need to use the provided straight-through
Ethernet cable. The straight-through cable, which is the “standard” Ethernet cable, is used to
connect devices of different types together, such as a PC to a Hub, or a Hub to a Cyclone.
At this point it once again becomes necessary to program the Cyclone with valid IP numbers, the
process for which is described in greater detail in the following section. However, it is important for
the Cyclone and the PCs to have matching Subnet and Gateway IP numbers, and for each to have
a unique IP number on the network. An example of a setting for above is as follows:
IP Number Gateway IP Subnet Mask
PC1 192.168.100.1 192.168.100.3 255.255.255.0
PC2 192.168.100.2 192.168.100.3 255.255.255.0
CYCLONE 192.168.100.4 192.168.100.3 255.255.255.0
Gateway 192.168.100.3 192.168.100.3 255.255.255.0
It is important to briefly touch upon the underlying network architecture, which can be a 10Mb
(Megabit), 100Mb, 10/100Mb, half-duplex, or a full-duplex connection. The details of the underlying
network architecture are beyond the scope of this document, but it is sufficient to note that most
modern network cards, as well as the Cyclone device, have the capability to configure themselves
for the underlying network through the Auto-negotiation mechanism. Auto-negotiation is performed
as soon as a network cable is connected to the device, and it sets the operating parameters of the
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device to match those of the network.
10.4.2 Connecting Cyclone-to-PC via an Ethernet cable
In order to connect the Cyclone to a PC directly via an Ethernet cable, you need to use what is
known as a cross-over cable. A cross-over cable, which is not provided by PEmicro, is normally
used to connect two similar devices such as a PC to a PC, or a Hub to a Hub. It is a cable that has
its receive and transmit wires crossed over so that the similar devices can effectively communicate
with one another.
With this configuration, it is still important to assign IP numbers to both the PC and the Cyclone
device. Although at first glance it may not seem necessary to assign a Gateway address in this
configuration, the Cyclone was designed to operate on a network of more than two computers, and
therefore it needs to be programmed with a Gateway address.
Assuming the desktop’s IP number to be 192.168.100.1, this is an example of the three IP
numbers that would need to be programmed into the Cyclone:
IP Number Gateway IP Subnet Mask
PC 192.168.100.1 none 255.255.255.0
CYCLONE 192.168.100.2 192.168.100.1 255.255.255.0
For more information on programming these IP numbers into the Cyclone device, please see the
following section.
10.5 Cyclone IP Setup Via LCD Menu
When the user is connecting the Cyclone via Ethernet, before the connection is established
between the Cyclone and the network the menu’s Home Screen will display the Cyclone’s IP
address as 0.0.0.0.
Once a connection has been established, the menu’s Home Screen displays the Cyclone’s IP
address and connection setting (Static or Dynamic).
The Ethernet cable can either be attached at the start of Cyclone startup or connected after setup
is complete. The connection with the network will be established when the cable is connected. If
the Ethernet cable is disconnected after setup is complete, the user should be able to simply
reconnect the cable to reestablish networking. However, depending on the setup of the DHCP
server, if the Ethernet cable is left unplugged for a considerable time the IP address may expire
and connection will have to be set up once again. This can be accomplished by restarting the
Cyclone.
10.5.1 Configure Network Settings
To configure network settings for the Cyclone, navigate to the following Menu location:
Main Menu / Configure Cyclone Settings / Configure Network Settings
The following options will be available under Configure Network Settings:
• Show Current IP Settings
• Edit Static IP Settings
• Enable/Disable Dynamic IP
• Edit Cyclone Name
10.5.1.1 Show Current IP Settings
Show Current IP Settings displays the current IP settings, including:
• Current IP Mode
• IP Number
• Mask
• Gateway
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• MAC Address
If you are in Static IP mode, these settings (excluding the MAC address) may be changed by
tapping on them. In this case a tap will take you to the Edit menus. If you are in Dynamic IP mode,
tapping will show a message that the Cyclone settings cannot be changed.
Dynamic vs. Static
There are two schemes for assigning IP addresses. One is the Static IP addressing mode. This
involves the user manually setting the IP address for every device on the network. In this case, it
falls to the user to ensure the IPs assigned do not conflict and are within the boundaries of the
network. The other is the Dynamic Host Configuration Protocol (DHCP). This involves setting up a
separate server to manage the IP addresses. The server is given a list of valid IP addresses for the
network. Using a predetermined set of rules, each new device that wishes to connect to the
network is given an IP address by the server. This takes the task of managing the validity and
uniqueness of IP addresses out of the user's hands and relegates it to the server. Cyclone LC
programmers are capable of using either Static IP addressing or DHCP.
Note: The current IP settings may also be viewed/edited by navigating to:
Main Menu / Status / Show Current IP Settings
10.5.1.2 Edit Static IP Settings
This allows editing of IP, Mask, and Gateway in Static IP mode. In the edit dialogs, the user must
enter a valid IP address to continue:
Format
xxx.xxx.xxx.xxx
Where:
0 <= xxx <= 255
10.5.1.3 Enable/Disable Dynamic IP
Opens a dialog to toggle the IP settings between Static and Dynamic. Once an option is selected a
message is displayed indicating that the Cyclone must be reset for this option to take effect. The
reset button on the front side of the Cyclone may be used.
10.6 Configuring Cyclone Network Settings using the Cyclone Control GUI
Before the Cyclone device transacts data on an Ethernet network, it will need to be configured with
the relevant network parameters. This configuration can be done in the "Properties" tab of the
Cyclone Control GUI.
To access the "Properties" tab, select the Cyclone from the drop-down list in the Cyclone Control
GUI and click on "Connect". The "Properties" tab will be accessible once the Cyclone is open.