[RTL8722CSM] [RTL8722DM] Power Save Deep Sleep DHT Eink

Materials

  • RTL8722DM x 1

  • DHT11 or DHT22 or DHT21 x 1

  • LCD I2C screen x 1

Example

Introduction

Ameba-D supports low power modes which are deepsleep mode. Deepsleep mode turns off most of the system power domain. The power consumptions of core module in DeepSleep Mode is around 7uA to 8uA compare to normal state around 22mA. This example gives demo of system switch between “working” and “sleep”(power save).Using DHT sensor to read data and display on Eink screen when system is awake. After 5 seconds system auto enter DeepSleep Mode for power save. System will wake up by wakeup source.( Aon timer, Aon Pins or RTC timer).

Procedure
Open “File” -> “Examples” -> “AmebaPowerSave” -> “DeepSleep_DHT_Eink_Example”
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Set condition values as picture below.
“DS_WAKEUP_SOURCE” is used to set the wake-up source, user can chose 3 wake up sources now,
AON timer (SET_DS_AON_TIMER_WAKEUP);
AON pins (SET_DS_AON_WAKEPIN_WAKEUP);
RTC timer (SET_DS_RTC_WAKEUP);

AON timer can be set from 0 to 32760000 range (unit ms) by AON_TIMER_SLEEP_DURATION

There are 4 pins can be set as AON pins and active high for wake-up, D16, D17, D26 and D27. The AON pin can be set by SET_DS_AON_WAKEPIN_WAKEUPPIN

RTC timer wake-up system by set alarm. The alarm has 4 values, day, hour, min and sec. All 4 values can be set by DS_RTC_ALARM_DAY, DS_RTC_ALARM_HOUR, DS_RTC_ALARM_MIN, and DS_RTC_ALARM_SEC

DHTPIN is used to set DHT sensor data pin. User can choose any GPIO pins.
DHTTYPE is used to set DHT sensor type. (DHT11, DHT22 and DHT33)
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When finished the condition values setting, system will run and switch between normal working mode and deepsleep mode controlled by wakeup source. Eink screen will display the temperature and humidity data measured from DHT sensor when system is awake.

Code Reference

Please refer to the API Documents PowerSave section for detail description of all API.