![](http://datasheet.mmic.net.cn/280000/M37902F8CHP_datasheet_16084061/M37902F8CHP_89.png)
89
M37902FCCHP, M37902FGCHP, M37902FJCHP
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
Fig. 93 Microcomputer internal register
’
s status at reset (2)
(80
16
)
···
Address
CS
0
control register L
(81
16
)
···
CS
0
control register H
(82
16
)
···
CS
1
control register L
(83
16
)
···
CS
1
control register H
(8C
16
)
···
Area CS
1
start address register
(84
16
)
···
CS
2
control register L
(85
16
)
···
CS
2
control register H
(86
16
)
···
CS
3
control register L
(87
16
)
···
CS
3
control register H
(8A
16
)
···
Area CS
0
start address register
(8E
16
)
···
Area CS
2
start address register
(90
16
)
···
Area CS
3
start address register
Notes 1:
The contents of the other registers and RAM are undefined at reset and must be initialized by software.
2:
While Vss level voltage is applied to pin MD0, this bit is
“
0
”
. While Vcc level voltage is applied to pin MD0, on the other hand, this bit is
“
1
”
.
3:
While Vss level voltage is applied to pin BYTE, these bits are
“
0
”
. While Vcc level voltage is applied to pin BYTE, on the other hand, these bits are
“
1
”
.
(92
16
)
···
Port function control register
(94
16
)
···
External interrupt input control register
(96
16
)
···
D-A control register
Address
0
1 0
(Note 3)
1 0
0
1 0
0
1 0
0
1 0
0
1 0
0
1 0
0
1 0
0
0 0 1
0
0 0 0
0
0 0 0
0
0 0 0
0
0 0 0
0
0 0 0
0
0 0 0
0
0 0 0
0 0 0
0
1
0 0 1
0
0
0
0 0 0
0
0
0
0 0 0
0 0 0 0
0 0 0 0
0 0 0
00
16
00
16
Program bank register PG
Contents at address FFFF
16
Program counter PC
H
Contents at address FFFE
16
Program counter PC
L
0000
16
Direct page registers DPR0 to DPR3
Data bank register DT
FFF
16
Stack pointer
(98
16
)
···
D-A register 0
(99
16
)
···
D-A register 1
(9A
16
)
···
D-A register 2
(A0
16
)
···
Real-time output control register
(AC
16
)
···
Serial I/O pin control register
(BC
16
)
···
Clock control register
0 0 0
0 0 0 0
0
0 0 0
0
1 1 1
(9E
16
)
···
Flash memory control register
0
0 0
0 0 1
0
0 0 0
0
0 0 0
0
00
16
00
16
00
16
Processor status register PS
1
0
0 0
0
0 0
(Note 3)
(Note 3)
(Note 3)
(Note 2)
RESET CIRCUIT
While the power source voltage satisfies the recommended operat-
ing condition, reset state is removed if pin RESET
’
s level returns
from the stabilized
“
L
”
level to the
“
H
”
level. As a result, program ex-
ecution starts from the reset vector address. This reset vector ad-
dress is expressed as shown below:
A
23
to A
16
= 00
16
A
15
to A
8
= Contents at address FFFF
16
A
7
to A
0
= Contents at address FFFE
16
Figures 92 and 93 show the microcomputer internal register
’
s status
at reset, and Figure 94 shows an operation example of the reset cir-
cuit. Apply
“
L
”
level voltage to pin RESET for a period (2 μs or more)
under the following conditions:
Pin Vcc
’
s level satisfies the recommended operating condition.
Oscillator
’
s operation has been stabilized.
Fig. 94 Operation example of reset circuit (Note that proper evalua-
tion is necessary in the system development stage.)
V
CC
RESET
Power on
V
CC
level
0.2V
CC
level
2
μ
s
Oscillation stabilized
X
IN
0V
0V
0V