Hello, it was a hardware problem. I had tried with two different Pro Mini boards, but after trying with a third one, everything is working now. Thank you for your help.

Thanks for your answers. I tried the code keeping only sleep without the other functions, and it worked once. When I uploaded another, more complex sketch, it didn’t work anymore, and even if I put back the one that used to work, it no longer works :
4098 TSF:MSG:SEND,22-22-0-0,s=100,c=1,t=48,pt=2,l=2,sg=0,ft=0,st=OK:1
4306 MCO:SLP:MS=5000,SMS=0,I1=255,M1=255,I2=255,M2=255
4311 TSF:TDI:TSL
4315 MCO:SLP:WUP=-1
4317 TSF:TRI:TSB
Réveillé !
4419 TSF:MSG:SEND,22-22-0-0,s=100,c=1,t=48,pt=2,l=2,sg=0,ft=0,st=OK:1
4628 MCO:SLP:MS=5000,SMS=0,I1=255,M1=255,I2=255,M2=255
4632 TSF:TDI:TSL
4636 MCO:SLP:WUP=-1
4638 TSF:TRI:TSB
Réveillé !

I think there is a problem with PIN 2 / IRQ because if I connect the IRQ to GND, there is a 5 s sleep, but then the radio no longer works.

13764 MCO:SLP:MS=5000,SMS=0,I1=255,M1=255,I2=255,M2=255
13770 TSF:TDI:TSL
13772 MCO:SLP:WUP=-1
13774 TSF:TRI:TSB
Réveillé !
20779 !TSF:MSG:SEND,22-22-0-0,s=100,c=1,t=48,pt=2,l=2,sg=0,ft=1,st=NACK:1

Hi,
I'm trying to put a node to sleep that consists of an Arduino Pro Mini board (3.3 V, 8 MHz) and an RFM95 module (SX1276 chip) using MySensors (2.4.0). In the code below, the node does not go to sleep. I've tried with and without transportDisable/transportReinitialise, and also cutting power to the RFM95 module using powerDownRadio / powerUpRadio, but whenever sleep actually works, the radio transmission no longer works after waking up… I don’t know what else to test. Any idea? Is it a hardware problem ?

#define MY_DEBUG
#define MY_RADIO_RFM95
#define MY_RFM95_FREQUENCY (RFM95_868MHZ)
#define MY_IRQ_PIN 2
#define MY_RST_PIN 9
#define MY_NODE_ID 22

#include <MySensors.h>

MyMessage msgTestRfm(100, V_CUSTOM);

void presentation() {
sendSketchInfo("Test RFM", "1.1");
present(100, S_CUSTOM);
}

void loop() {

send(msgTestRfm.set(1));
wait(200);

// couper la radio (sinon sleep() bloque)
transportDisable();
wait(50);

// sommeil — pas de LowPower ici !
sleep(5000);

// réactiver la radio
transportReInitialise();
wait(200);

Serial.println("Réveillé !");
}