TC1796
Peripheral Units (Vol. 2 of 2)
Controller Area Network (MultiCAN) Controller
User’s Manual
22-70
V2.0, 2007-07
MultiCAN, V2.0
Message Notifications
When a message object n generates an interrupt request upon the transmission or
reception of a message, then the request is routed to the interrupt output line selected
by the bit fields MOIPRn.TXIPND or MOIPRn.RXIPND of the message object n. As there
are more message objects than interrupt output lines, an interrupt routine typically
processes requests from more than one message object. Therefore, a priority selection
mechanism is implemented in the MultiCAN module to select the highest priority object
within a collection of message objects.
The Message Pending Register MSPNDk contains the pending interrupt notification of
list k.
MSPNDk (k = 0-7)
Message Pending Register k
(120
H
+k*4
H
)
Reset Value: 0000 0000
H
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
PND
rwh
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PND
rwh
Field
Bits
Type Description
PND
[31:0]
rwh
Message Pending
When a message interrupt occurs, the message
object sets a bit in one of the MSGPND register,
where the bit position is given by the MPN[4:0] field of
the IPR register of the message object. The register
selection n is given by the higher bits of MPN.
The register bits can be cleared by software (write 0).
Writing a 1 has no effect.