User`s guide

Universal Library User's Guide Temperature Input Boards - WLS Series
197
The level of noise per channel is system-dependent, and depends on the number of transmitters in the
local vicinity, including wireless telephones, video monitors, and so on.
You can set the RF channel using the ConfigItem option BIRFCHANNEL with cbSetConfig() while the
device is connected locally to the computer through the USB port.
 AES Key: The value used to encrypt a message (optional).
This value is disabled by default. To enable encryption, click the AES Key button and enter up to
16 alpha-numeric characters in the text box. This value is write-only; it cannot be read back.
Unless you suspect that there are other users of WLS Series devices in the area, there should be no need
to enable encryption. However, if you suspect that there are other WLS Series devices in the area, and
you need to secure the devices from being accessed by other users, enable this feature.
Note that enabling encryption does NOT secure the device from access through a local USB connection.
A remote device configured for encryption can be connected locally through the USB port to access other
remote WLS Series devices with the same settings; you may need to physically secure the remote devices
to prevent tampering of the of device's network.
Set the PAN ID, RF channel, and AES key to the same value for each device that you want to
communicate
Only devices with matching parameter settings for PAN ID, RF channel, and AES encryption (if set) can
communicate with each other.
InstaCal's configuration page also lists the unique 64-bit address assigned to the device. You cannot change
this address.
Use the Device Notes tab to enter up to 239 ASCII characters of additional text — for example, what the
device is measuring, and which device it is communicating with. You can set the text to store in the device's
memory using the ConfigItem option BIDEVNOTES with cbSetConfigString().
Received Signal Strength (wireless operations)
When a WLS Series device is operating remotely, InstaCal's configuration page includes a bar graph. The bar
graph indicates the strength of the signal received by the remote device from the wireless interface module,
and the fade margin of signals received by a device (refer to the following table.)
Active bars
fade margin
Rss (dBm)
0 – Weak signal
< 10 dBm
-82 dBm > rss
1 – Moderate signal
≥ 10 dBm
-72 dBm > rss >= -82 dBm
2 – Strong signal
≥ 20 dBm
-62 dBm > rss >= -72 dBm
3 – Very strong signal
≥ 30 dBm
rss > -62 dBm
The number of bars corresponds to the number of LEDs that are lit on the remote device. The bar graph
display updates every two seconds on the InstaCal form.
If the signal is not strong enough for communication between the interface device and the remote device, no
bars or LEDs show, and a NOREMOTEACK error is returned. If this occurs, try moving or re-orienting the device
to increase the strength of the signal
You can retrieve the value in dBm of the signal strength received by a remote device using the ConfigItem
option BIRSS with cbGetConfig().
External power required for wireless operations
An external power supply is required to power remote devices. For wireless operations, connect the device's
USB cable to the AC-to-USB power adapter that shipped with the device.