Generic helper functions (util.h)

Detailed Description

#include "util.h" 

Overview

Generic helper functions and macros

Functions
void	delay (uint16_t del)
void	delay_us (uint16_t us)
void	delay_ms (uint16_t ms)
void	delay_s (uint16_t s)
int	sgn (int x)
void	intToStr (uint32_t val, uint8_t digits, uint8_t fuellChar, char *dest)
void	intToHex (uint32_t val, uint8_t digits, uint8_t fuellchar, char *dest)
void	random_init (void)
uint32_t	random (void)

Macros
#define	_BV(bit)   (1l << (bit))
#define	RETURN_ERROR(value, max)   if ((value) > (max)) return 0;
#define	RANDOM_INIT_PIN_COUNT   5
#define	RANDOM_INIT_PIN_START   3
#define	PRESCALER_MS   1993l

Function Documentation

void delay

(

uint16_t

del

)

Delays for some CPU cycles

Parameters

del	Delay loop count

Definition at line 28 of file util.c.

void delay_us

(

uint16_t

us

)

Delays for N microseconds

Parameters

us	Number of microseconds to delay

Note

Uses Reload Timer 3!

Definition at line 34 of file util.c.

void delay_ms

(

uint16_t

ms

)

Delays for N milliseconds based on delay_us

Parameters

ms	Number of milliseconds to delay

Definition at line 41 of file util.c.

void delay_s

(

uint16_t

s

)

Delays for N seconds based on delay_ms

Parameters

s	Number of seconds to delay

Definition at line 46 of file util.c.

int sgn

(

int

x

)

Returns 1 for values greater 0, 0 for 0, -1 for values lower 0

Parameters

x	Value to check

Returns

Signum value of X

Definition at line 51 of file util.c.

void intToStr	(	uint32_t	val,
		uint8_t	digits,
		uint8_t	fuellChar,
		char *	dest
	)

Convert the given integer value (up to 32 bits, unsigned) to the string representing its decimal value.

Parameters

val	Integer to convert
digits	Number of digits the output string should have (1 - 10)
fuellChar	The character used for digits in front of the value
dest	Pointer to stringbuffer, 0 on errror

Definition at line 55 of file util.c.

void intToHex	(	uint32_t	val,
		uint8_t	digits,
		uint8_t	fuellchar,
		char *	dest
	)

Convert the given integer value (up to 32 bits, unsigned) to the string representing its hexadecimal value.

Parameters

val	Integer to convert
digits	Number of digits the output string should have (1 - 8)
fuellchar	The character used for digits in front of the value
dest	Pointer to stringbuffer, 0 on errror

Definition at line 78 of file util.c.

void random_init

(

void

)

Initialize the random number generator.

Definition at line 107 of file util.c.

uint32_t random

(

void

)

Get a random byte value. The initialization vector is created by reading out up to 4 ADC pins.

Returns

Random value

Note

random_init has to be called before the first call to random!

Definition at line 120 of file util.c.

Macro Definition Documentation

#define _BV

(

bit

)

(1l << (bit))

Sets the n-th bit of a byte

Parameters

bit	bit to set

Definition at line 39 of file util.h.

#define RETURN_ERROR	(		value,
			max
	)		if ((value) > (max)) return 0;

Returns 0 if the given value is greater than the given maximal value

Parameters

value	Value to check
max	Maximum value allowed

Definition at line 46 of file util.h.

#define RANDOM_INIT_PIN_COUNT   5

Number of ADC pins used for initialization of the RNG.

Definition at line 117 of file util.h.

#define RANDOM_INIT_PIN_START   3

First of the ADC pins used for initialization of the RNG.

Definition at line 122 of file util.h.

#define PRESCALER_MS   1993l

Prescaler used by the delay_ms routine to get loops of one millisecond each

Definition at line 127 of file util.h.