st72324bk STMicroelectronics, st72324bk Datasheet - Page 161

• Manufacturer Part Number: st72324bk
• Description: 3 V/5 V Range 8-bit Mcu With 4/8 Kbyte Rom, 10-bit Adc, Four Timers And Spi
• Manufacturer: STMicroelectronics

ST72323 ST72323L
14
14.1
14.2
Note:
Known limitations
Unexpected reset fetch
If an interrupt request occurs while a "POP CC" instruction is executed, the interrupt
controller does not recognize the source of the interrupt and, by default, passes the RESET
vector address to the CPU.
Workaround
To solve this issue, a "POP CC" instruction must always be preceded by a "SIM" instruction.
Clearing active interrupts outside interrupt routine
When an active interrupt request occurs at the same time as the related flag is being
cleared, an unwanted reset may occur.
Clearing the related interrupt mask will not generate an unwanted reset
Concurrent interrupt context
The symptom does not occur when the interrupts are handled normally, i.e. when:
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If these conditions are not met, the symptom can be avoided by implementing the following
sequence:
Perform SIM and RIM operation before and after resetting an active interrupt request.
Example:
Nested interrupt context
The symptom does not occur when the interrupts are handled normally, i.e. when:
●
●
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If these conditions are not met, the symptom can be avoided by implementing the following
sequence:
The interrupt flag is cleared within its own interrupt routine
The interrupt flag is cleared within any interrupt routine
The interrupt flag is cleared in any part of the code while this interrupt is disabled
SIM
reset interrupt flag
RIM
The interrupt flag is cleared within its own interrupt routine
The interrupt flag is cleared within any interrupt routine with higher or identical priority
level
The interrupt flag is cleared in any part of the code while this interrupt is disabled
PUSH CC
SIM
reset interrupt flag
POP CC
Known limitations
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