High Resolution Delay Timer

High-precision microsecond delay functionality. More...

Classes
class	DelayObject
	High-resolution microsecond delay timer class. More...

Detailed Description

High-precision microsecond delay functionality.

#include< HiResDelay.h>

The High Resolution Delay Timer provides microsecond-precision timing by utilizing hardware system timers. This is ideal for applications requiring precise timing control such as:

• Protocol timing requirements
• Sensor polling with specific intervals
• Hardware interface timing
• Signal generation

Usage Overview

When a DelayObject is created, it automatically allocates an available hardware system timer from the processor's timer pool. The timer remains allocated for the lifetime of the object and is automatically freed when the object goes out of scope or is destroyed.

Timing Precision

• Minimum delay: Platform-dependent, typically ~1-10 microseconds
• Maximum delay: Limited by 32-bit counter (up to ~4,294 seconds)
• Precision: Hardware timer precision (typically sub-microsecond)
• Accuracy: Depends on system load and interrupt latency

Example Usage

#include <HiResDelay.h>
 
void performPreciseTiming() {
    // Create delay object - allocates hardware timer
    static DelayObject myHiResDelay;
    
    // Verify timer was successfully allocated
    if (!myHiResDelay.valid()) {
        iprintf("Error: No free timers available\n");
        return;
    }
    
    // Perform precise delays
    myHiResDelay.DelayUsec(100);   // Delay 100 microseconds
    myHiResDelay.DelayUsec(200);   // Delay 200 microseconds
    myHiResDelay.DelayUsec(1000);  // Delay 1 millisecond
}
 
// Timer is automatically freed when object goes out of scope

Important Notes

• Hardware timers are a limited resource - check valid() after construction
• Delays block the calling task (use RTOS tasks for concurrent operations)
• Very short delays (<10us) may have reduced accuracy due to overhead
• For non-blocking timing, consider using the Interval Timer classes
• Static or global DelayObjects prevent timer reallocation overhead

Comparison with Other Timing Methods

Method	Resolution	Blocking	Use Case
OSTimeDly()	20ms (1 tick)	Yes	General delays
DelayObject	Microseconds	Yes	Precise hardware timing
IntervalTimer	Microseconds	No	Periodic callbacks
Stopwatch	Microseconds	No	Time measurement

See also

Interval Timer Interval Timer for non-blocking periodic operations

Stopwatch Timer Stopwatch for time measurement

OSTimeDly() Standard RTOS delay function