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M0A21/M0A23 Series
May 06, 2022
Page
639
of 746
Rev 1.02
M0
A21
/M
0
A
2
3
SE
RIES
TEC
H
NICAL
RE
FEREN
C
E
M
ANUAL
Interrupt Identify Register (CAN_IIDR)
Register
Offset
R/W
Description
Reset Value
CAN_IIDR
0x10
R
Interrupt Identifier Register
0x0000_0000
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
15
14
13
12
11
10
9
8
IntId
7
6
5
4
3
2
1
0
IntId
Bits
Description
[31:16]
Reserved
Reserved.
[15:0]
IntId
Interrupt Identifier (Indicates the Source of the Interrupt)
If several interrupts are pending, the CAN Interrupt Register will point to the pending interrupt with the highest
priority, disregarding their chronological order. An interrupt remains pending until the application software has
cleared it. If IntId is different from 0x0000 and IE (CAN_CON[1]) is set, the IRQ interrupt signal to the EIC is
active. The interrupt remains active until IntId is back to value 0x0000 (the cause of the interrupt is reset) or
until IE is reset.
The Status Interrupt has the highest priority. Among the message interrupts, the Message Object’ s interrupt
priority decreases with increasing message number.
A message interrupt i
s cleared by clearing the Message Object’s IntPnd bit (CAN_IFn_MCON[13]). The Status
Interrupt is cleared by reading the Status Register.
IntId Value
Meanings
0x0000
No Interrupt is Pending
0x0001-0x0020
Number of Message Object which caused the interrupt.
0x0021-0x7FFF
Unused
0x8000
Status Interrupt
0x8001-0xFFFF
Unused
Table 6.16-6 Source of Interrupts