Posted on October 18, 2005 at 13:01Hello all,
I get a random behavior when exiting the Low Power Wait For Interrupt mode on my STR710. I use Embedded Workbench from IAR.
When entering LPWFI; I do:
XTI_Init(); //initialize the XTI
XTI_LineModeConfig(XTI_Line15, XTI_RisingEdge); //Configure the line 15 mode ,select Rising edge trig
XTI_LineConfig(XTI_Line15, ENABLE); //Enable line 15 WAKEUP pin or RTC Alarm
XTI_LineModeConfig(XTI_Line12, XTI_RisingEdge); //Configure the line 12
XTI_LineConfig(XTI_Line12, ENABLE); //Enable line UART0 as EXT_INT
XTI_ModeConfig(XTI_WakeUpInterrupt, ENABLE); //Enable Wake-Up mode in the XTI
And then:
//Configure interrupt controller
EIC_IRQChannelPriorityConfig(XTI_IRQChannel,1); // set the interrupt priority for external interrupt
EIC_IRQChannelConfig(XTI_IRQChannel,ENABLE); // Enable external interrupt.
EIC_IRQConfig(ENABLE); // Enable the IRQ
After that; I actually enter the WFI mode, using:
SLOW(RTC_CLK); // Enter Slow mode with 32 KHz as sys clock
FLASHR->CR0 |= 0x8000; // set bit PWD: flash power down
for(int i=0; i
LPWFI(RTC_CLK,DISABLE); // Enter in LPWFI ( LPWFI clock = 32KHz RTC Clock, MVR disabled)
All of the previous lines work perfectly well, as I have monitored the slowed down clock on the CLKOUT on my MB393B eval board.
I however need to get out of this deep sleep; so the interrupt routine goes like this:
void XTI_IRQHandler(void)
{
XTIsource=XTI_InterruptLineValue();
XTI_PendingBitClear(XTIsource );
}
Knowing I had set the XTI_Line12 (the one for the UART0) correctly (I looked at the XTI registers) and it is programmed as
WakeUp and Interrupt, I should branch to the routine of my UART upon interrupt at this particular line. Actually, the value of XTIsource is correct when I recover from the mode. But the MCU executes the code in the related ISR randomly, sometimes it does, other times it does not.
The same thing happens with the RTC Alarm(line 15) as an external interrupt to wake me up.
Sometimes it branches, some other times it doesn't! I burn the code into Flash, and press reset (so the same code executes each time) and get a different behavior (branch, doesn't branch)
Any thoughts/ideas/comments on this situation?
Thank you,
tech
