fw_sys.c File Reference

#include "fw_sys.h"

Go to the source code of this file.

Functions
void	SYS_SetClock (void)
void	SYS_TrimClock (uint8_t vrtrim, uint8_t irtrim)
void	SYS_Delay (uint16_t t)
void	SYS_DelayUs (uint16_t t)

Variables
__CODE uint16_t	ticks_ms = (__CONF_FOSC / ((__CONF_CLKDIV == 0)? 1 : __CONF_CLKDIV) / __CLK_REF)
__CODE uint8_t	ticks_us = (__CONF_FOSC / ((__CONF_CLKDIV == 0)? 1 : __CONF_CLKDIV) / __CLK_REF / 1000)

Function Documentation

SYS_Delay()

void SYS_Delay

(

uint16_t

t

)

Definition at line 65 of file fw_sys.c.

{
    uint16_t i;
    do
    {
        i = ticks_ms;
        while (--i);
    } while (--t);
}

SYS_DelayUs()

void SYS_DelayUs

(

uint16_t

t

)

Definition at line 75 of file fw_sys.c.

{
    uint8_t i;
    do
    {
        i = ticks_us;
        while (--i);
    } while (--t);
}

SYS_SetClock()

void SYS_SetClock

(

void

)

Change system clock

• For SDCC only.
• For Keil C51, trim IRC in STC-ISP will be more accurate
• Invoke this in the beginning of main()

Definition at line 40 of file fw_sys.c.

{
#if defined (SDCC) || defined (__SDCC)
    uint16_t i = 0; uint8_t j = 5;
    P_SW2 = 0x80;
    if (CLKDIV != (__CONF_CLKDIV))
    {
        CLKDIV = (__CONF_CLKDIV);
        do { // Wait a while after clock changed, or it may block the main process
            while (--i);
        } while (--j);
    }
    P_SW2 = 0x00;
    SYS_SetFOSC(__CONF_IRCBAND, __CONF_VRTRIM, __CONF_IRTRIM, __CONF_LIRTRIM);
    while (--i); // Wait
#endif
}

SYS_TrimClock()

void SYS_TrimClock	(	uint8_t	vrtrim,
		uint8_t	irtrim
	)

Definition at line 58 of file fw_sys.c.

{
    uint16_t i = 0;
    SYS_SetFOSC(__CONF_IRCBAND, vrtrim, irtrim, __CONF_LIRTRIM);
    while (--i); // Wait
}

Variable Documentation

ticks_ms

__CODE uint16_t ticks_ms = (__CONF_FOSC / ((__CONF_CLKDIV == 0)? 1 : __CONF_CLKDIV) / __CLK_REF)

An approximate estimate of instruction cycles in one second, may vary in different compilers even differnt versions, adjust it if you find the delay too slow or fast.

Definition at line 30 of file fw_sys.c.

ticks_us

__CODE uint8_t ticks_us = (__CONF_FOSC / ((__CONF_CLKDIV == 0)? 1 : __CONF_CLKDIV) / __CLK_REF / 1000)

Definition at line 31 of file fw_sys.c.