2290461_en-US

Yes

MM9z1J638D Timed wakeup by PTBx only works for once

Hi there,

I got the timed wakeup function working with PTB1. But it only would wake up once from PTB1. Everything seems fine after the first wakeup, LIN and application code running no problem.

The second time going to SLEEP mode, the uC seems to go to a different state that I can't understand

the current draw slightly drops from normal operation, unlike the first time it goes to sleep where the current is basically zero
debugger loses connection and cannot reconnect
uC becomes secured.

The only way to get out of this state is by power cycling.

One more observation is that if the wakeup is triggered by LIN, there seems no issue waking up multiple times. Only if the wake up is triggered the timed wakeup PTB1, the issue occurs.

Here's my SLEEP mode configuration

#define  Wakeup_counter  (unsigned int) 10*1000 // counter value in terms of ALFCLK (1ms by default)
char Wakeup_counter_hi = (char) ((Wakeup_counter & 0xFF00U) >> 8); // get the high byte
char Wakeup_counter_lo = (char) ((Wakeup_counter & 0x00FFU) >> 0); // get the low byte

void Handle_SleepRequest()
{
....... // save parameters to EEPROM
RTIDisable(); 
ADCDisable();											
TsenseDisable();
B_GPIO_VSENSE = 0;
l_sys_irq_disable(BSC2_Node1);  	// only SCI!!!						
B_TIE_C3I = 0;	// LIN timer interrupt disabled										
IrqDisable();
B_GPIO_IN1_TCAP1 = 0; // PTB1 input buffer disconnected from Timer channel 1 - input capture
B_GPIO_OUT1_TCOMP1 = 1; // Timer channel 1 - output compare connected to PTB1 output buffer OR gate (needs to be configured to allow OC to generate a system wakeup)
B_GPIO_CTL |= B_GPIO_CTL_DIR1_MASK | B_GPIO_CTL_DIR1M_MASK; // set PTB1 to output 
B_GPIO_CTL |= 0|B_GPIO_CTL_PE1M_MASK; // PTB1 I/O to high impedance mode so that it's not connected to outside of MCU

// force internal PTB1 to low
B_TSCR1_TEN = 1;
B_TCTL1 	= B_TCTL1_OM1_MASK;           // clear on OC
B_CFORC_FOC1 = 1;          		// force OC to clear because TCTL1 set to clear on OC
B_TSCR1_TEN = 0; 		// disable the timer to setup timer
B_TCNT 		= 0x0000U; // reset counter 
B_TIOS_IOS1 = 1; // Timer channel 1 acts as an output compare to allow TC1 write	
/*Timer clock selection to be Timerclk/1 see table 647*/
B_TSCR2_PR0 = 0;
B_TSCR2_PR1 = 0;
B_TSCR2_PR2 = 0;

B_TSCR2_TCRE = 0; //Inhibits timer counter reset and couter continuews to run

			

// setup a rising edge on hitting the OC
B_TCTL1  	 = B_TCTL1_OM1_MASK | B_TCTL1_OL1_MASK; // configure to be set on OC
B_TC1Hi      = Wakeup_counter_hi; // compare register needs to write the high byte before low byte
B_TC1Lo      = Wakeup_counter_lo;
B_TFLG1_C1F  = 1; 					// enable Timer channel 1 to cause a hardware interrupt

ADCLpEnable();
B_PCR_WUEH_WUPTB1 = 1;	 // enable PTB1 as the internal timed wake up source
PCREnterSleepMode();
while(1) DO_NOTHING;	// should not reach here
}

My wakeup handling function

void Wakeup_Process(void){
if (B_PCR_CTL_OPM & 2) 
{       // Check if Wake Up from Sleep mode (see page RM3.0 110 Intermediate Mode)
       B_PCR_CTL = OPM_SET_NORMAL; // set normal mode
       while (!(B_PCR_SRH_WLPMF )) DO_NOTHING; // Wait for Clock Domain Change   
    }
else{
       if(!B_PCR_SR_HWRF) {
          PCRReset(); 
    	         }
	}
}

main function

void main ()
{
        SYS_Init();
	CPMUInit(&ClockConf);
	D2DInit((TYPE_D2DCLKDIV) ClockConf.D2dDiv);												
	XirqEnable(); // enable XIRQ -> isrD2DErr() "write-once" 

	Wakeup_Process(); // Process wakeup event to bring CPU to normal if it is waken up
	B_WD_CTL = WD_OFF;    	
	PCRInit(ClockConf.PCRprescaler);
	SYSStartupTrimming();
        ADCInit();
        GPIOInit();
	RTIInit();
	RTIEnable();
	IrqEnable();
	EEPROM_Init(0x05);// 6.25MHz busclk
        ReadEEPROM();
        for EVER {
                    ...... // main application loop
                    if (SleepRequested){Handle_SleepRequest();}
                 } 

}

Appreciate your help.