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CHAPTER 3 MEMORY SPACE, CPU AND CONTROL UNIT
3.8.4
Multiple EIT Processing
If two or more EIT sources occur at the same time, the CPU selects and accepts one
EIT source. After executing the EIT sequence, the CPU repeats monitoring for EIT
sources.
If no acceptable EIT source can be found at EIT source detection, the CPU executes
the instruction of the handler for the EIT source it accepted last.
Therefore, if two or more EIT sources occur at the same time, the handler execution
order of the sources depends on the following two elements:
• EIT source acceptance priority
• How other sources were masked when the source was accepted
■
EIT source acceptance priority
EIT source acceptance priority means the order in which a source for EIT sequence execution is
selected after the PS and PC are saved, the PC updated as necessary, and other sources
masked. The handler of the source previously accepted is not always executed first.
Table 3.8-3 "EIT source acceptance priority and masking of other sources" shows the EIT
source acceptance priority.
Table 3.8-4 "EIT handler execution order" shows the execution order of the handlers for the
concurrent EIT sources, considering the mask processing for other EIT sources after an EIT
source is accepted.
Table 3.8-3 EIT source acceptance priority and masking of other sources
Acceptance
priority
Source
Masking for other sources
1
Reset
Other sources are discarded.
2
Undefined instruction exception
Canceled
3
INT instruction
I flag = 0
Coprocessor absence trap
None
Coprocessor error trap
4
User interrupt
ILM = level of the accepted source
5
(NMI)
ILM=15
7
INTE instruction
ILM=4
8
Step trace trap
ILM=4
Summary of Contents for MB91150 Series
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Page 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
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Page 10: ...vi ...
Page 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Page 178: ...162 CHAPTER 5 I O PORTS ...
Page 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Page 240: ...224 CHAPTER 8 PPG TIMER ...
Page 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Page 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Page 362: ...346 CHAPTER 15 UART ...
Page 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Page 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Page 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
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