BNC 835 Programmer Manual - Manual (Page 7)

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random amount of time. If a second collision is detected, the data is again retransmitted after waiting
twice as long. This is known as exponential back off.
The TCP/IP setup requires the following:
• IP Address: Every computer/electronic device in a TCP/IP network requires an IP address. An IP
address has four numbers (each between 0 and 255) separated by periods.
For example: 192.168.1.50 is a valid IP address.
• Subnet Mask: The subnet mask distinguishes the portion of the IP address that is the network ID
from the portion that is the station ID. The subnet mask 255.255.0.0, when applied to the IP address
given above, would identify the network ID as 192.168 and the station ID as 1.50. All stations in the
same local area network should have the same network ID, but different station IDs.
• Default Gateway: A TCP/IP network can have a gateway to communicate beyond the LAN identified
by the network ID. A gateway is a computer or electronic device that is connected to two different
networks and can move TCP/IP data from one network to the other. A single LAN that is not
connected to other LANs requires a default gateway setting of 0.0.0.0. If you have a gateway, then the
default gateway would be set to the appropriate value of your gateway.
• MAC Address: A MAC address is a unique 48-bit value that identifies a network interface card to the
rest of the network. Every network card has a unique MAC address permanently stored into its
memory.
Interface between the instrument and other devices on the network is connected to a network via a
category five (CAT-5) interface cable . This cable uses four twisted pairs of copper insulators
terminated into an RJ45 connector. CAT-5 cabling is capable of supporting frequencies up to 100 MHz
and data transfer speeds up to 1 Gbps, which accommodates 1000Base-T, 100Base-T, and 10Base-T
networks.
Generally, a VISA I/O library (like NI-VISA™) is used on the server side to facilitate the
communications. A VISA installation on the controller is a prerequisite for remote control over LAN
interface. VISA is a standardized software interface library providing input and output functions to
communicate with instruments. For more information about VISA refer to the VISA library supplier’s
documentation.
Only the IP address or the device name is required for link setup. The IP address/device name is part
of the "visa resource string" used by the programs for identification and control of the instrument. The
visa resource string has the form:
TCPIP::ipaddr::inst0::INSTR
ipaddr has to be replaced by the IP address or the computer name of the instrument.
For instance, if the instrument has the IP address 192.168.1.50, TCPIP::192.168.1.50::inst0::INSTR is
the valid resource name. Specification of inst0 in the resource name is optional. In this example, also