Brainboxes RS232 User Manual
Page 15
Manual for BL-521 5_3.doc
© Copyright Brainboxes Limited 2004
Page 15 of 41
A server device in park or sniff mode periodically wakes up to listen to transmissions from the master. The client
device only transmits at these same times periodically. Also, in Park mode, a server device can have as many as
255-parked clients, as oppose to the usual limit of 7 clients. However, only 7 of the parked clients can be brought
from park mode to be active at the same time. For further information on low power modes and their operation
please see the Bluetooth website
www.bluetooth.org
The settings used for the low power modes can be changed to suit whatever
the application is that the devices are being used for. Increasing interval
times will reduce the power usage, but will also increase the response time of
the BL-521’s as they are “out of action” for much longer.
Max Interval: This is used to specify in milliseconds the maximum possible
time that should exist between server/client communication ‘slots’
Min Interval: This is used to specify in milliseconds the minimum possible time
that should exist between server/client communication ‘slots’
Attempt & Timeout: These are used to specify the number of attempts that the
client device will listen at the specified interval, if there is no data there the
first time it starts to listen.
Interactive Menu
Some RS232 devices (GPS devices for example) emit a continuous stream of data regardless of whether a cable is
connected. When there is no Bluetooth connection, this data (from the RS232 device) will be interpreted by the
converter as commands to (or interaction with) the menu and ultimately change settings (such as baud rate) that
render the converter inoperable. Selecting “off” for this setting will stop the converter being unwontedly re-
configured in this manner. Unfortunately, this will also disable all the functionality required for this configuration
application to interact with this product.
If you inadvertently select “off” for this setting, the menu/command interface (and thus the operation of the
configuration application on this device) will only be re-enabled by a long reset as documented below.
WARNING: Use with care: Selecting the “off” option of this feature will render further configuration impossible.