Silicon limitations

STM8AL3xxx STM8L052R8 STM8L1xxx6/8

10/18

DocID17922 Rev 6

1.1.6

Incorrect code execution when FLASH/EEPROM memory wakes up



from power down mode

Description

As a consequence, following behavior may be seen on some devices:



execution gets lost due to incorrect read of vector table.



Code running from RAM read an incorrect value from FLASH/EEPROM memory, when



Program execution gets corrupted when returning from RAM execution to FLASH

Workaround

wakeup. This could be done using clock divider (CLK_CKDIVR) or by activation of fast

wakeup feature by setting FHWU bit in CLK_ICKCR register. Original clock setting can be

reconfigured back by software after wakeup.

Code example, assuming no divider is used in application by default.

CLK_CKDIVR = 0x01;

_asm(“HALT”);

CLK_CKDIVR = 0x00;

The interrupt service routine executed after wakeup could either stay at slower clock speed,

or reconfigure clock setting. Care has to be taken to restore previous clock divider at the end

of interrupt routines when modifying clock divider.

No fix planned for this limitation.