User Manual
15
7.1.7
TCP ModBus
With an NL115 attached, the datalogger can be set up as a TCP ModBus Master or
Slave device. For information on configuring the datalogger as a TCP ModBus
Master or Slave, see the ModBus section of the datalogger manual.
7.1.8
DHCP
The IP address of the datalogger may be obtained through DHCP, if a DHCP
server is available. The DHCP address will be automatically assigned if there is a
DHCP server available and no static IP address has been entered. The IP address
should be available a few minutes after the datalogger has been powered up with
the NL115 attached and Ethernet cable plugged in. The IP address can be found
with the Device Configuration Utility’s Settings tab under TCP/IP info. It can
also be found using a CR1000KD attached to the datalogger. Go to Configure,
Settings | Settings, scroll down to IP Status and press the right arrow.
An IP address obtained through DHCP is not static but is leased for a period of
time set by the network administrator. The address may change, if the datalogger
is powered down.
7.1.9
DNS
The datalogger provides a DNS client that can query a DNS server to resolve a
fully qualified domain name. When a DNS server is available, domain names can
be used in place of the IP address in the datalogger instructions.
7.2
File Formats
This section covers the different types of files stored on the CF card.
7.2.1
Data Files
The datalogger stores data on the CF card in TOB3 format. TOB3 is a binary
format that incorporates features to improve reliability of the CF cards. TOB3
allows the accurate determination of each record’s time without the space required
for individual time stamps.
TOB3 format is different than the data file formats created when data are collected
via a communication link. Data files read directly from the CF card generally
need to be converted into another format to be used.
When TOB3 files are converted into another format, the number of records may
be slightly greater or less than the number requested in the data-table declaration.
There is always some additional memory allocated. When the file is converted,
this will result in additional records if no lapses occurred. If more lapses occur
than were anticipated, there may be fewer records in the file than were allocated.
The CardConvert software included in LoggerNet, PC400, and PC200 will convert
data files from one format into another.
7.2.2
Program Files
The CF card can be used to provide extra program-storage space for the
datalogger. Program files can be copied to the card while it is attached as a drive
on the computer. They can also be sent to the card using LoggerNet’s File
Control. They may also be copied from CPU memory to the card (or from the
card to CPU memory) using the CR1000KD.
