Datasheet
Table Of Contents
- 1. General Description
- 2. Electrical Characteristics
- 3. SX1272/73 Features
- 4. SX1272/73 Digital Electronics
- 4.1. The LoRaTM Modem
- 4.2. FSK/OOK Modem
- 4.2.1. Bit Rate Setting
- 4.2.2. FSK/OOK Transmission
- 4.2.3. FSK/OOK Reception
- 4.2.4. Operating Modes in FSK/OOK Mode
- 4.2.5. General Overview
- 4.2.6. Startup Times
- 4.2.7. Receiver Startup Options
- 4.2.8. Receiver Restart Methods
- 4.2.9. Top Level Sequencer
- 4.2.10. Data Processing in FSK/OOK Mode
- 4.2.11. FIFO
- 4.2.12. Digital IO Pins Mapping
- 4.2.13. Continuous Mode
- 4.2.14. Packet Mode
- 4.2.15. io-homecontrol® Compatibility Mode
- 4.3. SPI Interface
- 5. SX1272/73 Analog & RF Frontend Electronics
- 6. Description of the Registers
- 7. Application Information
- 8. Packaging Information
- 9. Revision History
www.semtech.comPage 120
SX1272/73
WIRELESS, SENSING & TIMING DATASHEET
Rev. 2 - July 2014
©2014 Semtech Corporation
T
TimeoutRxPreamble
should be set to the expected transmit preamble duration (depends on PreambleDetectSize and
BitRate).
T
Timer1
should be set to 64 µs (shortest possible duration).
T
Timer2
is set so that T
Timer1 +
T
Timer2
defines the time between two start of reception.
In order to ensure packet detection and optimize the receiver power consumption the received packet Preamble should be
defined so that T
Preamble =
T
Timer2
- T
SyncAddress
with T
SyncAddress
= (SyncSize + 1)*8/BitRate.
An example of DIO configuration for this mode is described in the following table:
Table 46 Listen Mode with PreambleDetect Condition Recommended DIO Mapping
LowPowerSelection 1: To Idle state
FromIdle 1: To Receive state on
T1 interrupt
FromReceive 101: To Sequencer off on
SyncAddress interrupt
FromRxTimeout 10: To LowPowerSelection
DIO Value Description
001CrcOk
1 00 FifoLevel
2 11 SyncAddress
300FifoEmpty
4 11 PreambleDetect – Note:
MapPreambleDetect bit should be set.