7220 Datasheet, PDF (53/303 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

FUNCTIONAL DESCRIPTION
2.5 Interrupts
2.5 Interrupts
Interrupts are used in the following cases.
q When there is a request to execute a higher priority routine than current processing routine.
q When it is necessary to process according to a certain timing.
The M37221M6-XXXSP/FP has 14 interrupt sources (including reset).
These are vector interrupts with a fixed priority sequence. Table 2.5.1 shows the interrupt sources, vector
addresses and the interrupt priority sequence.
M37220M3-XXXSP/FP
Refer to “CHAPTER 4. M37220M3-XXXSP/FP.”
Table 2.5.1 Interrupt sources, vector addresses and priority
Priority
Interrupt sources
Vector addresses
High-order byte Low-order byte
Remarks
1 Reset (Note)
2 CRT interrupt
3 INT2 interrupt
4 INT1 interrupt
5 Timer 4 interrupt
6 f(XIN)/4096 interrupt
7 VSYNC interrupt
8 Timer 3 interrupt
9 Timer 2 interrupt
10 Timer 1 interrupt
11 Serial I/O interrupt
12 Multi-master I²C-BUS interface interrupt
13 INT3 interrupt
14 BRK instruction interrupt
FFFF16
FFFD16
FFFB16
FFF916
FFF516
FFF316
FFF116
FFEF16
FFED16
FFEB16
FFE916
FFE716
FFE516
FFDF16
FFFE16
FFFC16
FFFA16
FFF816
FFF416
FFF216
FFF016
FFEE16
FFEC16
FFEA16
FFE816
FFE616
FFE416
FFDE16
Non-maskable
Active edge selectable
Active edge selectable
Active edge selectable
Active edge selectable
Non-maskable (software interrupt)
Note: Reset are included in the table because it operates in the same way as interrupts.
These 14-source, 14-vector interrupts have the priority sequence as shown in Table 2.5.1 (reset has a
higher priority than interrupts).
When two or more interrupt requests occur at the same sampling point, the interrupt with the higher priority
(in order of 1 to 14) is received. This priority sequence is determined by hardware, but priority processing
is possible to be varied by software, by using the interrupt enable bit and the interrupt disable flag.
2-26
7220 Group User’s Manual