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CHAPTER 3 CPU
3.7.6
Interrupt Level Mask Register (PS: ILM)
The interrupt level mask register (ILM) is a 3-bit register that indicates the level of the
interrupt currently accepted by the CPU.CHAPTER 7 INTERRUPT
■
Interrupt Level Mask Register (ILM)
Figure 3.7-12 shows the configuration of the interrupt level mask register (ILM). See "CHAPTER 7
INTERRUPT", for details about interrupts.
Figure 3.7-12 Configuration of the Interrupt Level Mask Register (ILM)
The interrupt level mask register (ILM) indicates the level of the interrupt currently accepted by the CPU.
The level is compared with the value of the IL0 to IL2 bits of the interrupt control register (ICR00 to
ICR15) set according to the interrupt request from the peripheral function. If the interrupt enable flag has
been set to enable (CCR: I = 1), the CPU processes the instruction only when the value (interrupt level) of
the interrupt request is smaller than the value indicated by these bits.
•
When an interrupt is accepted, the interrupt level value is set in the interrupt level mask register (ILM).
Thereafter, interrupts with the same or lower level are not accepted.
•
The interrupt level is set to the highest level, which is the interrupts disabled status, because the interrupt
level mask register (ILM) is initialized to all 0's by a reset.
•
Although an assembler instruction can use an 8-bit immediate value transfer instruction for transfer to
the interrupt level mask register (ILM), only the lower 3 bits of the data are used.
•
Interrupt level mask register (ILM) and interrupt level priority
ILM2
ILM1
ILM0
: ILM
0
0
0
Default value
⇒
13
14
15
bit
Table 3.7-3 Interrupt Level Mask Register (ILM) and Interrupt Level Priority
ILM2
ILM1
ILM0
Interrupt level
Interrupt level priority
0
0
0
0
Highest (interrupts disabled)
Lowest
0
0
1
1
0
1
0
2
0
1
1
3
1
0
0
4
1
0
1
5
1
1
0
6
1
1
1
7
Summary of Contents for MB90460 Series
Page 1: ...The following document contains information on Cypress products ...
Page 3: ......
Page 5: ......
Page 9: ...iv ...
Page 41: ...22 CHAPTER 1 OVERVIEW ...
Page 45: ...26 CHAPTER 2 NOTES ON HANDLING DEVICES ...
Page 83: ...64 CHAPTER 3 CPU ...
Page 95: ...76 CHAPTER 4 RESET ...
Page 107: ...88 CHAPTER 5 CLOCK ...
Page 131: ...112 CHAPTER 6 LOW POWER CONSUMPTION MODE ...
Page 175: ...156 CHAPTER 7 INTERRUPT ...
Page 181: ...162 CHAPTER 8 MODE SETTING ...
Page 223: ...204 CHAPTER 9 I O PORT ...
Page 237: ...218 CHAPTER 10 TIME BASE TIMER ...
Page 247: ...228 CHAPTER 11 WATCHDOG TIMER ...
Page 275: ...256 CHAPTER 12 16 BIT RELOAD TIMER ...
Page 373: ...354 CHAPTER 14 MULTI FUNCTIONAL TIMER ...
Page 485: ...466 CHAPTER 16 PWC Timer ...
Page 531: ...512 CHAPTER 17 UART ...
Page 559: ...540 CHAPTER 19 DELAYED INTERRUPT GENERATOR MODULE ...
Page 589: ...570 CHAPTER 20 8 10 BIT A D CONVERTER ...
Page 601: ...582 CHAPTER 21 ROM CORRECTION FUNCTION ...
Page 633: ...614 CHAPTER 23 512K 1024K BIT FLASH MEMORY ...
Page 645: ...626 CHAPTER 24 EXAMPLE OF F2 MC 16LX MB90F462 F462A F463A CONNECTION FOR SERIAL WRITING ...
Page 715: ...696 APPENDIX ...
Page 716: ...697 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 739: ......