SX1210I084T Semtech, SX1210I084T Datasheet - Page 38

• Manufacturer Part Number: SX1210I084T
• Description: IC SINGLE-CHIP RECEIVER 32-TQFN
• Manufacturer: Semtech

Specifications of SX1210I084T

• Frequency: 863MHz ~ 960MHz
• Sensitivity: -113dBm
• Data Rate - Maximum: 200 kbps
• Modulation Or Protocol: FSK, OOK
• Applications: Alarm Systems, Communication Systems
• Current - Receiving: 3mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 2.1 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Memory Size: -

As illustrated in Figure 30, for Buffered mode operation the NRZ data from the demodulator is not directly accessed
by the uC but stored in the FIFO and accessed via the SPI Data interface. This frees the uC for other tasks
between processing data from the SX1210, furthermore it simplifies software development and reduces uC
performance requirements (speed, reactivity). Note that in this mode the packet handler stays inactive.
An important feature is also the ability to empty the FIFO in Stby mode, ensuring low power consumption and
adding greater software flexibility.
Note that Bit Synchronizer is automatically enabled in Buffered mode. The Sync word recognition must be enabled
(RXParam_Sync_on=1) independently of the FIFO filling method selected (IRQParam_Fifo_fill_method).
After entering Rx in Buffered mode, the chip requires the uC to retrieve the received data from the FIFO. The FIFO
will actually start being filled with received bytes either; when a Sync word has been detected (in this case only the
bytes following the Sync word are filled into the FIFO) or when the Fifo_fill bit is asserted by the user - depending
on the state of bit, IRQParam_Fifo_fill_method.
In Buffered mode, the packet length is not limited i.e. as long as Fifo_fill is set, the received bytes are shifted into
the FIFO.
The uC software must therefore manage the transfer of the FIFO contents by interrupt and ensure reception of the
correct number of bytes. (In this mode, even if the remote transmitter has stopped, the demodulator will output
random bits from noise)
Rev 2– Sept 8
ADVANCED COMMUNICATIONS & SENSING
Data
5.4. Buffered Mode
Datapath
5.4.1. General Description
5.4.2. Rx Processing
th
, 2008
Rx
RECOG.
SYNC
Figure 30: Buffered Mode Conceptual View
SX1210
CONTROL
Page 38 of 73
(+SR)
FIFO
CONFIG
DATA
SPI
www.semtech.com
NSS_CONFIG
SCK
MOSI
MISO
NSS_DATA
IRQ_1
SX1210
IRQ_0