CHAPTER 7 INTERRUPT AND TEST FUNCTIONS
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User’s Manual U10676EJ3V0UM
Figure 7-6. Format of INT0 Edge Detection Mode Register (IM0)
3210
IM00IM01IM02IM03
Address
IM0
FB4H
Symbol
IM01 Specifies edge to be detected
IM00
0Rising edge
0
0Falling edge
1
1Both rising and falling edges
0
1Ignored (interrupt request flag is not set)
1
IM02 Noise eliminator select bit
0Selects noise eliminator
1Does not select noise eliminator
Sampling Standby release
Enabled
Disabled
Disabled
Enabled
IM03 Sampling clock
0
Note
1f
X
/64
Note
Φ
Note This value differs depending on the system clock frequency (fX).Caution When the contents of the edge detection mode register are changed, the interrupt request flagmay be set. Therefore, you should disable interrupts before changing the contents of the moderegister. Then, clear the interrupt request flag by using the CLR1 instruction to enable theinterrupts. If the contents of IM0 are changed and the sampling clock of fX/64 is selected, clearthe interrupt request flag 16 machine cycles after the contents of the mode register have beenchanged.