Hi,
I am using mc9s08dz96.
This is the first time I want to put the MCU to sleep. I want to use STOP3 mode. So far I have found that I need to set some registers before issuing the STOP command. I have made these settings according to the datasheet.
void _EntryPoint(void)
{
/* ### MC9S08DZ128_64 "Cpu" init code ... */
/* PE initialization code after reset */
/* Common initialization of the write once registers */
/* SOPT1: COPT=0,STOPE=1,SCI2PS=0,IIC1PS=0,??=0,??=0,??=0 */
setReg8(SOPT1, 0x20U);
/* SOPT2: COPCLKS=0,COPW=0,??=0,ADHTS=0,??=0,MCSEL=0 */
setReg8(SOPT2, 0x00U);
/* SPMSC1: LVWF=0,LVWACK=0,LVWIE=0,LVDRE=1,LVDSE=1,LVDE=1,??=0,BGBE=0 */
setReg8(SPMSC1, 0x1CU);
/* SPMSC2: ??=0,??=0,LVDV=0,LVWV=0,PPDF=0,PPDACK=0,??=0,PPDC=0 */
setReg8(SPMSC2, 0x00U);
/* System clock initialization */
/*lint -save -e923 Disable MISRA rule (11.3) checking. */
if (*(uint8_t*)0xFFAFU != 0xFFU) { /* Test if the device trim value is stored on the specified address */
MCGTRM = *(uint8_t*)0xFFAFU; /* Initialize MCGTRM register from a non volatile memory */
MCGSC = *(uint8_t*)0xFFAEU; /* Initialize MCGSC register from a non volatile memory */
}
/*lint -restore Enable MISRA rule (11.3) checking. */
/* MCGC2: BDIV=0,RANGE=1,HGO=0,LP=0,EREFS=0,ERCLKEN=1,EREFSTEN=1 */
setReg8(MCGC2, 0x23U); /* Set MCGC2 register */
/* MCGC3: DIV32=1 */
setReg8Bits(MCGC3, 0x10U);
/* MCGC1: CLKS=2,RDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=1 */
setReg8(MCGC1, 0x9BU); /* Set MCGC1 register */
/* MCGC3: LOLIE=0,PLLS=0,CME=0,DIV32=1,VDIV=4 */
setReg8(MCGC3, 0x14U); /* Set MCGC3 register */
/* MCGT: ??=0,??=0,DMX32=0,??=0,??=0,??=0,??=0,DRST_DRS=0 */
setReg8(MCGT, 0x00U); /* Set MCGT register */
while(MCGSC_IREFST != 0U) { /* Wait until external reference is selected */
}
while((MCGSC & 0x0CU) != 0x08U) { /* Wait until external clock is selected as a bus clock reference */
}
/* MCGC2: BDIV=0,RANGE=1,HGO=0,LP=1,EREFS=0,ERCLKEN=1,EREFSTEN=1 */
setReg8(MCGC2, 0x2BU); /* Set MCGC2 register */
/* MCGC1: CLKS=2,RDIV=2,IREFS=0,IRCLKEN=1,IREFSTEN=1 */
setReg8(MCGC1, 0x93U); /* Set MCGC1 register */
/* MCGC3: DIV32=0 */
clrReg8Bits(MCGC3, 0x10U);
/* MCGC3: LOLIE=0,PLLS=1,CME=0,DIV32=0,VDIV=4 */
setReg8(MCGC3, 0x44U); /* Set MCGC3 register */
while(MCGSC_PLLST == 0U) { /* Wait until PLL is selected */
}
/* MCGC2: LP=0 */
clrReg8Bits(MCGC2, 0x08U);
while(MCGSC_LOCK == 0U) { /* Wait until PLL is locked */
}
/* MCGC1: CLKS=0,RDIV=2,IREFS=0,IRCLKEN=1,IREFSTEN=1 */
setReg8(MCGC1, 0x13U); /* Set MCGC1 register */
while((MCGSC & 0x0CU) != 0x0CU) { /* Wait until PLL clock is selected as a bus clock reference */
}
/*** End of PE initialization code after reset ***/
/*lint -save -e950 Disable MISRA rule (1.1) checking. */
__asm jmp _Startup ; /* Jump to C startup code */
/*lint -restore Enable MISRA rule (1.1) checking. */
}
Next, I put the "__asm stop;" command in the main(),
void main(void)
{
PE_low_level_init();
while(1){
__asm stop;
}
}
But I don't see any change that the power consumption has decreased. In fact, I expect the device's consumption to reach microamps after the stop command, instead of the usual 30mA. Is " __asm stop; " command correct? Shouldn't I define it before this command?
Thank you for your help.
