EM2420-STR Ember, EM2420-STR Datasheet - Page 33

• Manufacturer Part Number: EM2420-STR
• Description: IC RF TXRX ZIGBEE 2.4GHZ 48-QLP
• Manufacturer: Ember

Specifications of EM2420-STR

• Mfg Application Notes: EM2420
• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4
• Applications: ZigBee™
• Power - Output: -3dBm
• Sensitivity: -94dBm
• Voltage - Supply: 2.1 V ~ 3.6 V
• Current - Receiving: 19.7mA
• Current - Transmitting: 17.4mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-QLP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Memory Size: -

values will make the system non-802.15.4-
compliant, which could be desirable in
some cases.
A
transmitted first in all transmit modes.
The preamble sequence length can be set
by MDMCTRL0.PREAMBLE_LENGTH, while
the SFD is programmed in the SYNCWORD
register. SYNCWORD is 2 bytes long, which
gives the user some extra flexibility as
described below. Figure 16 shows how the
EM2420
the IEEE 802.15.4 specification.
The programmable preamble length only
applies to transmission. It does not affect
receive
should not be set shorter than the default
value. Note that 2 of the 8 zero-symbols in
the preamble sequence required by [1] are
included in the SYNCWORD register so that
the
Length field
The frame length field shown in Figure 15
defines the number of bytes in the MPDU.
Note that the length field does not include
the length field itself. However, it does
include
Sequence),
automatically by the
also includes the MIC if authentication is
used.
Ember Part Number: 120-0049-000D
IEEE 802.15.4
synchronization
EM2420
EM2420
synchronization header relates to
mode.
the
preamble sequence is only 6
even
FCS
The
2·(PREAMBLE_LENGTH + 1) zero symbols
0
if
header
EM2420
Figure 16. Transmitted Synchronization Header
preamble
this
(Frame
0
hardware. It
is
is
inserted
0
always
Check
length
SW0 = SYNCWORD[3:0]
SW1 = SYNCWORD[7:4]
SW2 = SYNCWORD[11:8]
SW3 = SYNCWORD[15:12]
EM2420 Datasheet
Preamble
0
Synchronization Header
0
symbols long for compliance with [1]. Two
additional zero symbols in SYNCWORD
make the
In reception, the
received zero-symbols and searches for
the
SYNCWORD register. The least significant
symbols in SYNCWORD set to 0xF will be
ignored, while symbols different from 0xF
will be required for synchronization. The
default setting of 0xA70F thereby requires
one
synchronization. This will reduce the
number of false frames detected due to
noise.
In receive mode the
preamble
synchronization
adjustments. The SFD is used for byte
synchronization, and is not part of the data
stored in the receive buffer (RXFIFO).
The length field is 7 bits and has a
maximum
significant bit in the length field is reserved
[1], and should be set to zero.
The
transmission and reception, so this field
must
implementing a proprietary (non 802.15-4)
system. In transmit mode, the length field
is used for underflow detection, as
described in the FIFO access section on
page 27.
EM2420
SFD
0
always
if different from 'F', else '0'
if different from 'F', else '0'
if different from 'F', else '0'
if different from 'F', else '0'
additional
EM2420
SW0
value
sequence
uses the length field both for
0
sequence
be
compliant with [1].
EM2420
and
SW1
of
0
included
zero-symbol
EM2420
EM2420
127.
frequency
defined
synchronizes to
SW2
for
7
SFD
The
Page 33 of 84
uses the
even
SW3
by
symbol
A
offset
most
the
for
if