User's Manual

Table Of Contents
Document : WCAMODHEL.sxw
0xFF 0x02 0x06 0x40 0x0E 0x01
0xXXX
X
0x0
3
Response from the WaveCard to the host (RES_WRITE_RADIO_PARAM)
HEADER
SYN
C
STX LENGT
H
CMD
D ATA
Status of the update
CRC ETX
0xFF 0x02 0x05 0x41 0x00 0xXXX
X
0x0
3
3.1.2 - Wake Up and synchronization mechanism
In the purpose to optimize power consumption, the Wavecard is in a STANDBY mode and is wakening up
periodically to poll a radio activity. The wakeup period is given by the value of the AWAKENING_PERIOD
parameter, expressed in multiples of 100ms (1 second by default).
a) Principle when transmitting, or receiving a frame
When transmitting a frame to a distant equipment, the transmitter begins an awakening preamble called
'WakeUp' being used to awake the receiving equipments which will position then in radio reception. This
preamble results in the sending on the radio medium, of a binary succession of symbol.
This awakening preamble (WakeUp) can be of two types,
Long WakeUp : used when transmitting a request towards distant equipment. Its duration can be
parameterized by the user (1100ms by default); and is generally equal to the WakeUp period of
the equipment to address, plus 100ms, in order to avoid transmitting between two periods of
reception.
Short WakeUp : used only when responding to a point-to-point request. Its duration is equal to
50ms, and cannot be configured.
NUM DESCRIPTION VALUE
SIZE (in
bytes)
0x00
AWAKENING_PERIOD : polling period of RF medium
radio, in multiples of 100ms
Period in multiples of 100ms
(by default, 0x0A for one second)
0 = quasi-permanent reception (every
20ms)
1
0x01
WAKEUP_TYPE : Wake Up type used during a frame
emission
0 : long Wake Up (default setting)
1 : short Wake Up = 50 ms
1
WCAMODHEL Handbook page 17 of 74