M16C Datasheet, PDF (70/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Preliminary Specifications REV.B
Mitsubishi microcomputers
Specifications in this manual are tentative and subject to change.
M16C / 6N Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
IPnrteecrrauupttiosns _{for Interrupts}
CAN0/1 Wake Up Interrupt
A CAN Wake Up interrupt is generated after one of the CAN buses becomes active. That means the physical
bus turns to a dominant level.
This interrupt can only be used to wake up the CPU from wait mode or stop mode.
The CAN Wake Up interrupt can only be used, if the port(s) are configured as CAN ports. One interrupt signal
is generated for both CAN channels.
Please note that the Wake Up message wiil be lost.
Figure 6-8 shows the principle to generate the corresponding interrupt signal.
CAN0/1 Wake Up int. control register (address 0041 16)
CRX0
CRX1
Figure 6-14. CAN 0/1 Wake Up interrupt
Interrupt control circuit
CAN Wake Up
interrupt request
Precautions for Interrupts
(1) Reading address 00000₁₆
•When the maskable interrupt occurs, CPU reads the interrupt information (the interrupt number and inter-
rupt request level) in the interrupt sequence.
The interrupt request bit of the certain interrupt written in address 00000₁₆ will then be set to "0".
Reading address 00000₁₆ by software sets enabled highest priority interrupt source request bit to "0".
Though the interrupt is generated, the interrupt routine may not be executed.
Do not read address 00000₁₆ by software.
(2) Setting the stack pointer
•The value of the stack pointer immediately after reset is initialized to 0000₁₆. Accepting an interrupt before
setting a value in the stack pointer may become a factor of runaway. Be sure to set a value for the stack
pointer before accepting an interrupt. When using the NMI interrupt, initialize the stack point at the begin-
ning of a program. Concerning the first instruction immediately after reset, generating any interrupt includ-
ing the NMI interrupt is prohibited.
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