delay on AN3825 seems to be wrong

gsradiotelefoni — Wed, 27 Nov 2013 17:12:24 GMT

On AN3825SW I found up these delays but I don't agree with them.

My opinion is that with a bus clock of 4MHz each cycle is 0.25 uS long.

It means that 100uS cannot be 4000/400=10 cycles of FOR in the routine

void Delay_100us(void)

A FOR is using 8 cicles + 1 NOP it means 9*0.25uS= 2.25uS

The same problem seems to be on the remaining delay.

Is it correct or I am wrong.

Thanks

ByeBye

* *

*******************************************************************************

* Example for MC9S08SG8 - Metronom + LCD + Buttons *

* - Li-Ion Charger *

* - DC/DC Bosst Converter *

******************************************************************************/

//----- MCU Definitions --------------------

#define BUS_SPEED 4000 // BusCLK in kHz;

#define DELAY1MS BUS_SPEED/22

#define DELAY100US BUS_SPEED/400

#define TIMER2DIV 128

//*****************************************************************************

void Delay_100us(void)

{

word i;

for (i = 0;i<=DELAY100US;i++)

{

asm nop;

}

//*****************************************************************************

void Delay_1ms(void)

{

word i;

for (i = 0;i<=DELAY1MS;i++)

{

asm nop;

}

//*****************************************************************************

void WaitNms(word n)

{

int j;

for(j=1;j<=n;j++)

{

Delay_1ms();

__RESET_WATCHDOG();

}

topic delay on AN3825 seems to be wrong in 8-bit Microcontrollers