NRF24LE1 Power down mode

[tass]

Hi, i try to understand how to use power down modes. But i have a problem in the example (nRF24LE1 REGISTER RETENTION TIMER ON).

while(1)
{
// Register retention mode
PWRDWN = 0x04;
// Standby mode (wait for interrupt)
PWRDWN = 0x07;
// Clear PWRDWN
PWRDWN = 0x00;
// Continue to run code
P03 = !P03; 
};

I would like to ask why after the chip enters register retention mode, we need standby mode. Thanks...

[Stefan Birnir Sverrisson]

Hi

When waking up on RTC timer there is a «pre tick» event that occurs some time before the actual tick, so that you have time to start the 16MHz clock before the actual tick occurs. While waiting for the tick, after the pre tick happens, you can enter standby mode to reduce power consumption.