Page 292 of 346 Start Back Next End ZBasic System Library 280 ZBasic Microcontrollers Sleep Type Subroutine Invocation Sleep(time) Parameter Method Type Description time ByVal Single or int16 The amount of time to delay, in seconds (Single) or ticks (int16) Discussion This routine suspends the current task for a period of time up to as long as specified. If the RTC is not enabled in your application, the resolution of the delay period is 1mS. If the RTC is enabled, the resolution is the same as an RTC tick period, i.e. 1/F_RTC_TICK (typically 1.95mS for ZX devices). The actual sleep time experienced by the calling task depends on what other tasks actually do that may run in the interim. It is possible that the task will be suspended indefinitely depending on what another task might do. Note that if the current task is locked, this call will unlock it. There is a subtle difference between Delay() and Sleep() when the RTC is enabled and the arguments are non-zero. For Delay() the specified time is the minimum amount of delay that the task will experience assuming that no other task is ready to run and the actual delay could be up to 1 unit longer than the specified delay. For Sleep(), the specified time is the maximum amount of delay that the task will experience assuming that no other task is ready to run and the actual delay could be up to 1 unit less than the specified delay. It is important to note that internally, the sleep function utilizes an integral tick value. If the supplied parameter is a Single value it is converted to the equivalent integral number of ticks (if the value is a known constant at compile time, otherwise at run time). Consequently, if a Single value is specified that is less than the equivalent of one tick the sleep time will be zero ticks. Example Do Call PutPin(Pin.RedLED, 0) Call Sleep(0.5) ' a half-second delay Call PutPin(Pin.RedLED, 1) Call Sleep(256) ' a half-second delay Loop This loop causes the red LED to turn on and off alternately for a half second each. Compatibility The BasicX documentation specifically indicates that Sleep() will unlock a locked task. However, tests indicate that this only happens if the parameter to Sleep() is non-zero. This implementation unlocks a task on any Sleep() call. See Also Delay, DelayUntilClockTick, Pause, WaitForInterval, Register.RTCStopWatch