/**
* @brief This API configures modify system HIRC value
* @param[in] u8FsysMode . Valid values are:
* - \ref HIRC_24 :Internal HIRC 24MHz .
* - \ref HIRC_16 :Internal HIRC 16MHz.
* - \ref HIRC_166 :Internal HIRC 16.6MHz.
* @NOTE None.
* @exmaple : MODIFY_HIRC(HIRC_24);
*/
void MODIFY_HIRC(unsigned char u8HIRCSEL)
{
unsigned char data hircmap0,hircmap1;
unsigned int trimvalue16bit;
/* Check if power on reset, modify HIRC */
SFRS = 0 ;
switch (u8HIRCSEL)
{
case HIRC_24:
IAPAL = 0x38;
break;
case HIRC_16:
IAPAL = 0x30;
break;
case HIRC_166:
IAPAL = 0x30;
break;
}
set_CHPCON_IAPEN;
IAPAH = 0x00;
IAPCN = READ_UID;
set_IAPTRG_IAPGO;
hircmap0 = IAPFD;
IAPAL++;
set_IAPTRG_IAPGO;
hircmap1 = IAPFD;
clr_CHPCON_IAPEN;
switch (u8HIRCSEL)
{
case HIRC_166:
trimvalue16bit = ((hircmap0 << 1) + (hircmap1 & 0x01));
trimvalue16bit = trimvalue16bit - 15;
hircmap1 = trimvalue16bit & 0x01;
hircmap0 = trimvalue16bit >> 1;
break;
default: break;
}
TA = 0xAA;
TA = 0x55;
RCTRIM0 = hircmap0;
TA = 0xAA;
TA = 0x55;
RCTRIM1 = hircmap1;
clr_CHPCON_IAPEN;
PCON &= CLR_BIT4;
}
|
楼主
