SM1211E915TOPIC Semtech, SM1211E915TOPIC Datasheet - Page 34

• Manufacturer Part Number: SM1211E915TOPIC
• Description: KIT PICTAIL EXT FOR SX1211
• Manufacturer: Semtech
• Type: Transceiver, UHFr

Specifications of SM1211E915TOPIC

• Frequency: 915MHz
• For Use With/related Products: SX1211
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5. Data Processing
Figure 25, illustrates the SX1211 data processing circuit. Its role is to interface the data to/from the
modulator/demodulator and the uC access points (SPI, IRQ and DATA pins). It also controls all the configuration
registers.
The circuit contains several control blocks which are described in the following paragraphs.
The SX1211 implements several data operation modes, each with their own data path through the data processing
section. Depending on the data operation mode selected, some control blocks are active whilst others remain
disabled.
The SX1211 has three different data operation modes selectable by the user:
Rev 7 – Sept 2
ADVANCED COMMUNICATIONS & SENSING
5.1. Overview
Continuous mode: each bit transmitted or received is accessed in real time at the DATA pin. This mode may be
used if adequate external signal processing is available.
Buffered mode: each byte transmitted or received is stored in a FIFO and accessed via the SPI bus. uC
processing overhead is hence significantly reduced compared to Continuous mode operation. The packet
length is unlimited.
Packet mode (recommended): user only provides/retrieves payload bytes to/from the FIFO. The packet is
automatically built with preamble, Sync word, and optional CRC, DC free encoding and the reverse operation is
performed in reception. The uC processing overhead is hence reduced further compared to Buffered mode.
The maximum payload length is limited to the maximum FIFO limit of 64 bytes
Data
5.1.1. Block Diagram
5.1.2. Data Operation Modes
nd
Tx/Rx
, 2008
Tx
Rx
SYNC
RECOG.
Figure 25: SX1211’s Data Processing Conceptual View
PACKET
HANDLER
SX1211
CONTROL
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FIFO
(+SR)
CONFIG
DATA
SPI
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SX1211
MISO
SCK
MOSI
NSS_DATA
IRQ_1
DATA
IRQ_0