HUAWEI ME909u-523 LTE LGA Module
Application Guide
Sleeping and Waking Up Application Scenarios
Issue 04 (2014-12-08)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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Figure 8-4
SLEEP_STATUS PIN output sequence
8.3 Software Interfaces
8.3.1
Principle
The module runs on a multi-task software system. The sleep task is granted with the
lowest priority and assigned to detect whether the module can enter sleep mode.
Other tasks (such as the RF, SIM card, USB) have voting rights. They vote to decide
whether the module can enter sleep mode. When no other tasks are running, the
sleep task is executed. If the sleep task detects that all other tasks agree on the
module's sleep, the module enters sleep mode, as shown in Figure 8-5 . At this time,
the baseband chip reduces the work frequency, and the RF enters the Discontinuous
Reception (DRX) mode.
Figure 8-5
Currency state when the module is in sleep mode
T 2 ( S
E E
L
P )
T 1 ( W a k e u p )
For more information about the module's sleep procedure, see Figure 8-6 .
