| err | [BusinessError](https://gitee.com/openharmony/docs/pulls/20172/files#businesserror) | Yes | Common error information about the API invoking failure.|
| err | [BusinessError](#businesserror) | Yes | Common error information about the API invoking failure.|
| isNano | boolean | No | Whether the time to return is in nanoseconds.<br>- **true**: The time to return is in nanoseconds.<br>- **false**: The time to return is in milliseconds.|
| isNano | boolean | No | Whether the time to return is in nanoseconds. The default value is **false**.<br>- **true**: The time to return is in nanoseconds.<br>- **false**: The time to return is in milliseconds.|
**Return value**
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@@ -253,7 +257,7 @@ Obtains the time elapsed since system startup, excluding the deep sleep time. Th
| isNano | boolean | No | Whether the time to return is in nanoseconds.<br>- **true**: The time to return is in nanoseconds.<br>- **false**: The time to return is in milliseconds.|
| isNano | boolean | No | Whether the time to return is in nanoseconds. The default value is **false**.<br>- **true**: The time to return is in nanoseconds.<br>- **false**: The time to return is in milliseconds.|
**Return value**
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@@ -348,7 +352,7 @@ Obtains the time elapsed since system startup, including the deep sleep time. Th
| isNano | boolean | No | Whether the time to return is in nanoseconds.<br>- **true**: The time to return is in nanoseconds.<br>- **false**: The time to return is in milliseconds.|
| isNano | boolean | No | Whether the time to return is in nanoseconds. The default value is **false**.<br>- **true**: The time to return is in nanoseconds.<br>- **false**: The time to return is in milliseconds.|
**Return value**
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@@ -380,6 +384,8 @@ Sets the system date. This API uses an asynchronous callback to return the resul
| type | number | Yes | Timer type.<br>**1**: CPU time type. (The start time of the timer cannot be later than the current system time.)<br>**2**: wakeup type.<br>**4**: exact type.<br>**8**: idle type (not supported currently).|
| repeat | boolean | Yes | Whether the timer is a repeating timer.The value **true** means that the timer is a repeating timer, and **false** means that the timer is a one-shot timer. |
| interval | number | No | Repeat interval.For a repeating timer, the value must be greater than 5000 ms. For a one-shot timer, the value is **0**.|
| repeat | boolean | Yes | Whether the timer is a repeating timer.<br>The value **true** means that the timer is a repeating timer, and **false** means that the timer is a one-shot timer. |
| interval | number | No | Repeat interval.<br>For a repeating timer, the value must be greater than 5000 ms. For a one-shot timer, the value is **0**.|
| wantAgent | [WantAgent](js-apis-app-ability-wantAgent.md) | No | **WantAgent** object of the notification to be sent when the timer expires. (An application MainAbility can be started, but not a Service ability.)|
| callback | number | Yes | Callback used to return the timer ID. |