Busy-Wait Delay Routines

This module provides simple loop-based delay routines for those applications requiring a brief wait during execution. More...

Macros
#define	delay_init(fcpu_hz)
	Initialize the delay driver.
#define	delay_ms(delay)
	Delay in milliseconds.
#define	delay_s(delay)
	Delay in seconds.
#define	delay_us(delay)
	Delay in microseconds.
#define	F_CPU   sysclk_get_cpu_hz()
	MCU Clock Frequency (Hertz).

Detailed Description

This module provides simple loop-based delay routines for those applications requiring a brief wait during execution.

Common API for UC3, XMEGA, and AVR MEGA.

Macro Definition Documentation

delay_init

#define delay_init

(

fcpu_hz

)

Initialize the delay driver.

Parameters

fcpu_hz

CPU frequency in Hz

Deprecated

This function is provided for compatibility with ASF applications that may not have been updated to configure the system clock via the common clock service; e.g. sysclk_init() and a configuration header file are used to configure clocks.

The functions in this module call sysclk_get_cpu_hz() to obtain the system clock frequency.

Definition at line 98 of file delay.h.

delay_ms

#define delay_ms

(

delay

)

Value:

((delay) ? cpu_delay_ms(delay, F_CPU) : cpu_delay_us(1, F_CPU))

Delay in milliseconds.

Parameters

delay

Delay in milliseconds

Definition at line 112 of file delay.h.

delay_s

#define delay_s

(

delay

)

Value:

((delay) ? cpu_delay_ms(1000 * delay, F_CPU) : cpu_delay_us(1, F_CPU))

Delay in seconds.

Parameters

delay

Delay in seconds

Definition at line 105 of file delay.h.

delay_us

#define delay_us

(

delay

)

Value:

((delay) ? cpu_delay_us(delay, F_CPU) : cpu_delay_us(1, F_CPU))

Delay in microseconds.

Parameters

delay

Delay in microseconds

Definition at line 119 of file delay.h.

F_CPU

#define F_CPU   sysclk_get_cpu_hz()

MCU Clock Frequency (Hertz).

Deprecated

The F_CPU configuration constant is used for compatibility with the Busy-Wait Delay Routines routines. The common loop-based delay routines are designed to use the Legacy clock management group alias modules while anticipating support for legacy applications assuming a statically defined clock frequency. Applications using a statically configured MCU clock frequency can define F_CPU (Hertz), in which case the common delay routines will use this value rather than calling sysclk_get_cpu_hz() to get the current MCU clock frequency.

Definition at line 80 of file delay.h.