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 58
SX1272/73
WIRELESS, SENSING & TIMING DATASHEET
Rev. 2 - July 2014
©2014 Semtech Corporation
4.2.9.3. Timers
Two timers (Timer1 and Timer2) are also available in order to define periodic sequences. These timers are used to
generate interrupts, which can trigger transitions of the Sequencer.
T1 interrupt is generated (Timer1Resolution * Timer1Coefficient) after T2 interrupt or SequencerStart. command.
T2 interrupt is generated (Timer2Resolution * Timer2Coefficient) after T1 interrupt.
The timer mechanism is summarized on the following diagram.
Figure 24. Timer1 and Timer2 Mechanism
Note The timer sequence is completed independently of the actual Sequencer state. Thus, both timers need to be on to
achieve periodic cycling.
FromPacketReceived
Controls the state-machine transition from the PacketReceived state:
000: to SequencerOff state
001: to Transmit on a FifoEmpty interrupt
010: to LowPowerSelection
011: to Receive via FS mode, if frequency was changed
100: to Receive state (no frequency change)
T2
interrupt
T1
interrupt
Timer1
Timer2
Sequencer Start