Strange SPI (nrf24l01) behaviour after wakeup

[maksz]

Hi! I have a problem with SPI after wakeup. I use nrf24l01 radio. When I set powerDown arduino gets wrong data. The program lights diode when it receives 0 and vice versa. The problem is when it goes power down and wakes up from an interrupt (onReceive), it reads byte wrong. I checked on serial port and it reads 1 instead of 0, 0 instead of 1 and it randomly changes. The data which the radio receives is correct. If there is no power down the program is working as expected. I can’t figure it out. I use version 1.8. Thanks.

#include <LowPower.h>
#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>

#define diode 5

RF24 radio(7, 8); // CE, CSN

const byte address[6] = "00001";

volatile unsigned long pingTime = 0;;

void onReceive(){
  bool message;
  radio.read(&message, sizeof(message));
  digitalWrite(diode, !message);
  pingTime = millis();
}

void connectionLost(){
  digitalWrite(diode, LOW);
  delay(424);
  digitalWrite(diode, HIGH);
  delay(424);
}

void setup() {
  pinMode(diode, OUTPUT);
  digitalWrite(diode, HIGH);
  radio.begin();
  radio.openReadingPipe(0, address);
  radio.setPALevel(RF24_PA_MAX);
  radio.maskIRQ(1,1,0);
  radio.setChannel(29);
  radio.setDataRate(RF24_2MBPS);
  radio.startListening();
  attachInterrupt(0, onReceive, LOW);
  
  if (radio.available()){
    onReceive();
  }
  pingTime = millis();
}

void loop() {
  unsigned long timeNow = millis();
  noInterrupts();
  bool isTimeout = timeNow - pingTime > 9000;
  bool ISRErrCheck = pingTime <= timeNow;
  interrupts();
  if(isTimeout && ISRErrCheck){
    connectionLost();
  }
  LowPower.powerDown(SLEEP_4S, ADC_OFF, BOD_OFF); //NOT working if present
}

[RileyMueller]

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