Renesas M16C Laptop User Manual


 
Rev.1.10 Jul 01, 2005 page 77 of 318
REJ09B0124-0110
M16C/6N Group (M16C/6NK, M16C/6NM) 9. Interrupt
Under development
This document is under development and its contents are subject to change.
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9.7 NMI Interrupt
_______ _______ ______
An NMI interrupt request is generated when input on the NMI pin changes state from high to low. The NMI
interrupt is a non-maskable interrupt.
_______
The input level of this NMI interrupt input pin can be read by accessing the P8_5 bit in the P8 register.
This pin cannot be used as an input port.
9.8 Key Input Interrupt
Of P10_4 to P10_7, a key input interrupt request is generated when input on any of the P10_4 to P10_7
pins which has had the PD10_4 to PD10_7 bits in the PD10 register set to 0 (input) goes low. Key input
interrupts can be used as a key-on wake up function, the function which gets the microcomputer out of wait
or stop mode. However, if you intend to use the key input interrupt, do not use P10_4 to P10_7 as analog
input ports. Figure 9.14 shows the block diagram of the key input interrupt. Note, however, that while input
on any pin which has had the PD10_4 to PD10_7 bits set to 0 (input mode) is pulled low, inputs on all other
pins of the port are not detected as interrupts.
Interrupt control circuit
KUPIC register
Key input interrupt
request
KI3
KI2
KI1
KI0
PU25 bit in PUR2 register
PD10_7 bit in PD10 register
Pull-up
transistor
PD10_7 bit in PD10 register
PD10_6 bit in
PD10 register
PD10_5 bit in
PD10 register
PD10_4 bit in
PD10 register
Pull-up
transistor
Pull-up
transistor
Pull-up
transistor
Figure 9.14 Key Input Interrupt Block Diagram
9.9 CAN0/1 Wake-up Interrupt
CAN0/1 wake-up interrupt request is generated when a falling edge is input to CRX0 or CRX1. One interrupt
is allocated to CAN0/1. The CAN0/1 wake-up interrupt is enabled only when the PortEn bit = 1 (CTX/CRX
function) and Sleep bit = 1 (Sleep mode enabled) in the CiCTLR register (i = 0, 1). Figure 9.15 shows the
block diagram of the CAN0/1 wake-up interrupt. Please note that the wake-up message will be lost.
Figure 9.15 CAN0/1 Wake-up Interrupt Block Diagram
CRX1
Interrupt control
circuit
C01WKIC register
PortEn bit in C0CTLR register
PortEn bit in C1CTLR register
Sleep bit in C0CTLR register
Sleep bit in C1CTLR register
CRX0
CAN0/1 wake-up
interrupt request