M38867E8AHP MITSUBISHI [Mitsubishi Electric Semiconductor], M38867E8AHP Datasheet - Page 23

• Manufacturer Part Number: M38867E8AHP
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER??
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

Key Input Interrupt (Key-on Wake Up)
A Key input interrupt request is generated by applying “L” level to
any pin of port P3 that have been set to input mode. In other
words, it is generated when AND of input level goes from “1” to
Fig. 18 Connection example when using key input interrupt and port P3 block diagram
P 3
P 3
P 3
P 3
P 3
P 3
P 3
P 3
7
6
5
4
o u t p u t
o u t p u t
o u t p u t
o u t p u t
3
2
1
0
i n p u t
i n p u t
i n p u t
i n p u t
P o r t P X x
“ L ” l e v e l o u t p u t
P o r t c o n t r o l r e g i s t e r 1
B i t 5 = “ 1 ”
P o r t c o n t r o l r e g i s t e r 1
B i t 4 = “ 1 ”
P o r t P 3 1
l a t c h
P o r t P 3 7
l a t c h
P o r t P 3 6
l a t c h
P o r t P 3 5
l a t c h
P o r t P 3 4
l a t c h
P o r t P 3 3
l a t c h
P o r t P 3 2
l a t c h
P o r t P 3 0
l a t c h
d i r e c t i o n r e g i s t e r = “ 1 ”
d i r e c t i o n r e g i s t e r = “ 1 ”
d i r e c t i o n r e g i s t e r = “ 1 ”
d i r e c t i o n r e g i s t e r = “ 1 ”
d i r e c t i o n r e g i s t e r = “ 0 ”
d i r e c t i o n r e g i s t e r = “ 0 ”
d i r e c t i o n r e g i s t e r = “ 0 ”
d i r e c t i o n r e g i s t e r = “ 0 ”
P o r t P 3
P o r t P 3
P o r t P 3
P o r t P 3
P o r t P 3
P o r t P 3
P o r t P 3
P o r t P 3
“0”. An example of using a key input interrupt is shown in Figure
18, where an interrupt request is generated by pressing one of the
keys consisted as an active-low key matrix which inputs to ports
P3
7
6
0
–P3
5
4
3
2
1
0
3
.
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
P - c h a n n e l t r a n s i s t o r f o r p u l l - u p
C M O S o u t p u t b u f f e r
K e y i n p u t i n t e r r u p t r e q u e s t
3886 Group
P o r t P 3
I n p u t r e a d i n g c i r c u i t
C o m p a r a t o r c i r c u i t
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