M16C62N Datasheet, PDF (58/213 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Watchdog Timer
Mitsubishi microcomputers
M16C / 62N Group (80-pin)
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
BCLK
Write to the watchdog timer
start register
(address 000E16)
RESET
Prescaler
1/16
“CM07 = 0”
“WDC7 = 0”
1/128
“CM07 = 0”
“WDC7 = 1”
“CM07 = 1”
1/2
Watchdog timer
Set to
“7FFF16”
Figure 1.11.1. Block diagram of watchdog timer
“PM12 = 0”
Watchdog timer
interrupt request
Reset
“PM12 = 1”
Watchdog timer control register
b7 b6 b5 b4 b3 b2 b1 b0
00
Symbol
WDC
Address
000F16
Bit symbol
Bit name
High-order bit of watchdog timer
Reserved bit
Reserved bit
WDC7
Prescaler select bit
When reset
000XXXXX2
Function
Must always be set to “0”
Must always be set to “0”
0 : Divided by 16
1 : Divided by 128
RW
Watchdog timer start register
b7
b0
Symbol
WDTS
Address
000E16
When reset
Indeterminate
Function
RW
The watchdog timer is initialized and starts counting after a write instruction to
this register. The watchdog timer value is always initialized to “7FFF16”
regardless of whatever value is written.
Figure 1.11.2. Watchdog timer control and start registers
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