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3.3. Demastering Buttons
When a Nova Helix system is commissioned, all buttons learnt into the receiver are
granted master privileges for that receiver. From a security perspective, this is not
always desirable. To overcome this potential security issue, the system has the ability to
‘demaster’ master buttons.
1. Press and hold a master button that is associated with the same functionality as the
buttons that need to be demastered. The master button must be pressed for between
20 and 30 seconds.
2.
After the first 10 seconds, the receiver will beep once to indicate that it has entered
the learn mode time window. The user must continue to hold down the master
button.
3. Upon exit from the learn mode window, and entry to the demaster mode window, at
20 seconds, the receiver issues a long double beep.
4. Following the long double beep, the master button must be released. At this point the
receiver transitions to demaster mode.
5.
The LED will flash periodically with two quick flashes (64ms on/256ms off) and then a
longer pause (352ms). (Refer to Appendix A on page 30 for a description of the LED
and buzzer feedback) The receiver will only enter demastering mode for a particular
channel. The receiver will remain in demastering mode for a period of 10 seconds
failing any additional button presses.
6. While the receiver is in demastering mode, any mastered button that is pressed
for three or more seconds (but less than 10 seconds) and is associated with the
functionality that the receiver is currently demastering, is itself demastered. As with
learn mode, buttons are acted upon on their trailing edge - referred to as ‘trailing
edge demastering’ - this means the button is only demastered when it is released.
7. The leading edge of the transmitter transaction is acknowledged with a short beep.
This beep occurs irrespective of whether the button is a master button or not.
8. The receiver will demaster a button if, and only if, the button is a master button and
is associated with the channel of the master that placed the receiver in demastering
mode. A demastering operation is acknowledged with a short triple beep.
The triple beep acknowledgement is the point at which the transmitter button is
primed for demastering. Actual demastering only takes place when the button is
released. If the button is not released, and is held pressed for a total of 10 or more
seconds, then the button enters the deletion window (refer to the section, Deleting
Buttons, for further information on this operation).
9. If no additional buttons are pressed within the 10s demastering period, the receiver
will automatically exit demaster mode. This exit is signalled by an extended single
beep. The Status LED also stops flashing and resumes its responsibilities in normal
mode.
TH
E
MAS
TER
TRANS
MITTER
INTERFACE
S
ECTION
3
