Newport XPS-D, Руководство для стартапов

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XPS-D Controller Start-Up Manual
2.7 Ethernet Configuration
Figure 10: Ethernet configuration.
2.7.1 Communication Protocols
The Ethernet connection provides a local area network through which information is
transferred in units known as packets. Communication protocols are necessary to dictate
how these packets are sent and received. The XPS Controller/Driver supports the
industry standard protocol TCP/IP.
TCP/IP is a “connection” protocol and in this protocol, the master must be connected to
the slave in order to begin communication. Each packet sent is acknowledged when
received. If no acknowledgment is received, the information is assumed lost and is
resent.
2.7.2 Addressing
There are two levels of addresses that define Ethernet devices. The first is the MAC
address. This is a unique and permanent 6 byte number. No other device will have the
same MAC address. The second level of addressing is the IP address. This is a 32-bit
(or 4 byte) number. The IP address is constrained by each local network and must be
assigned locally. Assigning an IP address to the controller can be done in a number of
ways (see section 3.5: “Connecting to the XPS”).
2.8 Sockets, Multitasking and Multi-user Applications
Based on the TCP/IP Internet communication protocol, the XPS controller has a high
number of virtual communication ports, known as sockets. To establish communication,
the user must first request a socket ID from the XPS controller server (listening at a
defined IP number and port number). When sending a function to a socket, the
controller will always reply with a completion or error message to the socket that has
requested the action.
The concept and application of sockets have many advantages. First, users can split
their application into different segments that run independently on different threads or
even on different computers. To illustrate this, see below:
In this example, a thread on socket 1 commands an XY stage to move to certain
positions to take pictures while another thread on socket 2 independent of socket 1,
concurrently manages an auto-focusing system. The second task could even be run on a
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