CHAPTER 12 INTERRUPT FUNCTIONS
User’s Manual U16898EJ3V0UD
220
(3) External interrupt mode register 0 (INTM0)
This register is used to set the valid edge of INTP0 to INTP2.
INTM0 is set with an 8-bit memory manipulation instruction.
Reset signal generation clears INTM0 to 00H.
Figure 12-4. Format of External Interrupt Mode Register 0 (INTM0)
Address: FFECH After reset: 00H R/W
Symbol
7 6 5 4 3 2 1 0
INTM0 ES21 ES20 ES11 ES10 ES01 ES00 0
0
ES21
ES20
INTP2 valid edge selection
0
0
Falling
edge
0
1
Rising
edge
1
0
Setting
prohibited
1
1
Both rising and falling edges
ES11
ES10
INTP1 valid edge selection
0
0
Falling
edge
0
1
Rising
edge
1
0
Setting
prohibited
1
1
Both rising and falling edges
ES01
ES00
INTP0 valid edge selection
0
0
Falling
edge
0
1
Rising
edge
1
0
Setting
prohibited
1
1
Both rising and falling edges
Cautions 1. Be sure to clear bits 0 and 1 to 0.
2. Before setting the INTM0 register, be sure to set the corresponding interrupt mask flag
(
××
MK
×
= 1) to disable interrupts. After setting the INTM0 register, clear the interrupt
request flag (
××
IF
×
= 0), then clear the interrupt mask flag (
××
MK
×
= 0), which will
enable interrupts.