You could use an MQTT broker. If there's a message waiting for a node when it wakes up, it will read it.
You could use an RTC to control the wake time so that both are live at the same time.
Or send Request/Acknowledge semaphores.
You could use an MQTT broker. If there's a message waiting for a node when it wakes up, it will read it.
You could use an RTC to control the wake time so that both are live at the same time.
Or send Request/Acknowledge semaphores.