Jump to main content

##

# 1.2.11.4.29 SYS_TIME_CALLBACK Typedef

## C

    typedef void (*SYS_TIME_CALLBACK ) ( uintptr_t context );

## Summary

Pointer to a time system service callback function.

## Description

This data type defines a pointer to a time service callback function, thus defining the function signature. Callback functions may be registered by clients of the time service either when creating a software timer or using the SYS_TIME_Callback shortcut functions.

## Precondition

The time service must have been initialized using the SYS_TIME_Initialize function before attempting to register a SYS Time callback function.

## Parameters

Param | Description
--- | ---
context | A context value, returned untouched to the client when the callback occurs. It can be used to identify the instance of the client who registered the callback.

## Returns

None.

## Example

    //"MY_APP_DATA_STRUCT" is a user defined data structure with "isTimerExpired" as
    //one of the structure members.
    void MyCallback ( uintptr_t context )
    {
        MY_APP_DATA_STRUCT* pAppData = (MY_APP_DATA_STRUCT *) context;

        if (pAppData != NULL)
        {
            pAppData->isTimerExpired = true;
        }
    }

## Remarks

None.