RFM92 Datasheet, PDF (113/126 Pages) List of Unclassifed Manufacturers – Low Power Long Range Transceiver Module

RFM92W/93W V3.0
7.2.2. Manual Reset
A manual reset of the RFM92W/93W is possible even for applications in which VDD cannot be physically disconnected.
Pin 6 should be pulled high for a hundred microseconds and then released. The user should then wait for 5 ms before
using the chip.
VDD
Pin 6
(input)
> 100 us
Wait for
5 ms
High-Z ’’1’’ High-Z
Chip is ready from
this point on
Figure 46. Manual Reset Timing Diagram
Note Whilst pin 6 is driven high an over current consumption of up to ten milliampere can be seen on VDD.
7.3. Top Sequencer: Listen Mode Examples
In this scenario the circuit spends most of the time in Idle mode during which only the RC oscillator is on. Periodically the
receiver wakes up and looks for incoming signal. If a wanted signal is detected the receiver is kept on and data are
analyzed. Otherwise, if there was no wanted signal for a defined period of time, the receiver is switched off until the next
receive period.
During Listen mode the Radio stays most of the time in a Low Power mode resulting in very low average power
consumption. The general timing diagram of this scenario is given in Figure 47.
Listen mode : principle
Receive
Idle ( Sleep + RC )
Receive
Idle
Figure 47. Listen Mode: Principle
An interrupt request is generated on a packet reception. The user can then take appropriate action.
Depending on the application and environment, there are several ways to implement Listen mode:
Š Wake on a PreambleDetect interrupt.
Š Wake on a SyncAddress interrupt.
Š Wake on a PayloadReady interrupt.
7.3.1. Wake on Preamble Interrupt
In one possible scenario, the sequencer polls for a Preamble detection. If a preamble signal is detected, the sequencer is
switched off and the circuit stays in Receive mode until the user switches modes. Otherwise, the receiver is switched off
until the next Rx period.
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