Instruction manual

SECTION 5. NETADMIN
5-4
The DO___RETRIES USING A ____ SEC
PERIOD THEN USE ______ SEC. prompts
allow the scheduling of fast and slow retries.
When an operation (e.g., clock set) fails, it is
retried until it succeeds, is canceled by the user,
or is canceled by the program that initiated it.
This parameter allows the user to control how
often these retries occur. The number of retries
specified in the first blank are attempted at the
interval specified in the second blank. If the
operation is still unsuccessful it is then retried at
the second interval until it succeeds.
NOTE: These intervals must be long
enough to complete the entire operation
including telecommunication time. For
example, a large program may take 10 to 15
seconds to download and compile, even on
a direct connection. If the retry interval is not
long enough, the download will restart before
the previous one completes.
5.1.3 SERLINE PARAMETER (SERIAL LINE
COMMUNICATIONS)
The POLLING INTERVAL parameter is used to
specify how often the affected node (or child
nodes for some parent nodes) is checked for
data. Several factors are affected by it:
1. Delay from when data is stored in the
datalogger until it is available in the com-
puter. Polling a station once a minute
ensures the data is available at (or at least
en route to) the computer within a minute of
it being stored in datalogger memory.
2. How much time the network is active and
busy versus amount of time idle. The delay
involved in non-data type operations (e.g.,
clock sets) is affected by how busy the
network is polling. Polling at fast rates may
cause other jobs of lower priority to be
delayed or even postponed indefinitely.
3. The cost of running the network is affected;
frequent polls means frequent phone calls
in telephone networks. Frequent polling in
other networks causes more power con-
sumption, increasing demands on batteries.
NOTE: For RF Radio frequency, poll at
least every 20 minutes.
The OFFSET parameter is used to determine
when, in the polling interval, a poll is made. For
example, setting the polling interval to 60 and
the offset to 30, would cause the polling to take
place every minute (60 seconds) but 30
seconds into the minute.
The EXTRA COMMS ALLOWANCE (Msec) is
used to increase the amount of time DLSMGR
will wait for a response to serial packet data it
sends. Normally this is left at zero.
The MAX PACKET SIZE is used to manually
decrease the size of packets DLSMGR uses.
This is only required for special links. Normally
the default value is used.
The BAUD RATE parameter should be set to
match the selected device.
5.1.4 VIA PARAMETERS
This parameter is used to specify the link
between the node being described and the
parent node. For nodes connected directly to
the PC it specifies the COM port used. For a
remote station accessed by telephone it
specifies the telephone number dialed to reach
the station. For RF it is the hardware addresses
of the station and repeaters used to reach the
remote site. For MD9 networks it specifies the
hardware addresses of the remote MD9 nodes.
5.1.5 RF POLL OFFSET
In an RF network, the base polls the remotes at
the same interval it is polled by the computer.
This box is present for the first child of the RF
base node. It can be used to alter when, in the
polling interval, the RF begins polling. This
allows independent polling offsets for when the
computer polls the RF base and when the RF
base polls the remotes. For example, if the
datalogger stores data on the even minute,
starting the RF polling 5 seconds after that
ensures the most recent data is available.
5.1.6 STATUS LINE
The bottom of the screen contains a one line
status box. Relevant status information is
displayed.
5.1.7 EXAMPLES
Following is a description of what nodes need to
be entered for various communication
configurations. Network descriptions can use
multiple serial ports. For example, a modem on
COM1 can communicate with a network of
dataloggers via telephone lines while a RF base
on COM2 uses radio to communicate with other
dataloggers. The PC1 (computer) node is
present in all networks.