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Chapter 19
CAN Controller (CAN)
Preliminary User’s Manual U17566EE1V2UM00
19.1.2
Configuration
The CAN Controller is composed of the following four blocks.
• NPB interface
This functional block provides an NPB (NEC Peripheral I/O Bus) interface
and means of transmitting and receiving signals between the CAN module
and the host CPU.
• MAC (Memory Access Controller)
This functional block controls access to the CAN protocol layer and to the
CAN RAM within the CAN module.
• CAN protocol layer
This functional block is involved in the operation of the CAN protocol and its
related settings.
• CAN RAM
This is the CAN memory functional block, which is used to store message
IDs, message data, etc.
Figure 19-1
Block diagram of CAN module
CPU
CAN RAM
NPB
interf
a
ce
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ffer 0
CnMA
S
K1
CnMA
S
K2
CnMA
S
K
3
CnMA
S
K4
...
f
CAN
INTCnERR
INTCnWUP
INTCnREC
INTCnTRX
T
S
OUTCn
PCLK0
16 MHz
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bu
ffer 1
Me
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ffer 2
Me
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bu
ffer
3
Me
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3
1
MAC
(Memory Acce
ss
Controller)
CAN
protocol
l
a
yer
CAN mod
u
le
NPB
(NEC peripher
a
l
bus
)
CTXDn
CRXDn
CAN
tr
a
n
s
ceiver
CAN_Hn
CAN_Ln
CAN
bus
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