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LH75400/01/10/11 (Preliminary) User’s Guide
Controller Area Network
6/17/03
22-13
22.3.2.5 Interrupt Enable Register
IER is the Interrupt Enable Register. This register selects the events that are indicated to the
CPU through an interrupt being generated. It appears to the CPU as Read/Write memory.
Table 22-10. IER Register
BIT
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
FIELD
///
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RW
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
BIT
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FIELD
///
BEIE ALIE EPIE
///
DOIE
EIE
TIE
RIE
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RW
R
R
R
R
R
R
R
R
RW
RW
RW
RW
RW
RW
RW
RW
ADDR
0xFF 0x10
Table 22-11. IER Register Definitions
BITS
NAME
DESCRIPTION
31:8
///
Reserved
Writing to these bits has no effect. Reading returns 0.
7
BEIE
Bus Interrupt Error Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when a bus error is detected.
6
ALIE
Arbitration Lost Interrupt Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when the CAN Controller loses arbitration.
5
EPIE
Error Passive Interrupt Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when the error status of the CAN Controller changes from error
active to error passive or vice versa.
4
///
Reserved
3
DOIE
Data Overrun Interrupt Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when bit [1] of the Status Register is set (see Section 22.3.2.3).
2
EIE
Error Warning Interrupt Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when the Bus Status bit ([bit [7]) or the Error Status bit (bit [6])
of the Status Register change (see Section 22.3.2.3).
1
TIE
Transmit Interrupt Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when a message has been successfully transmitted or when
the transmit buffer is accessible.
0
RIE
Receive Interrupt Enable
0 = Interrupt is disabled.
1 = An interrupt is generated when bit [0] of the Status Register is full (see Section 22.3.2.3).
This bit influences bit [0] of the Interrupt Register (described in Section 22.3.2.4) and the
external interrupt output, NINT. If RIE clears, NINT becomes inactive (HIGH) immediately if
no other interrupt is pending.