M30845FJGP#U3 Renesas Electronics America, M30845FJGP#U3 Datasheet - Page 157

• Manufacturer Part Number: M30845FJGP#U3
• Description: IC M32C MCU FLASH 512K 144LQFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M32C/80r

Specifications of M30845FJGP#U3

• Core Processor: M32C/80
• Core Size: 16/32-Bit
• Speed: 32MHz
• Connectivity: CAN, I²C, IEBus, SIO, UART/USART
• Peripherals: DMA, PWM, WDT
• Number Of I /o: 121
• Program Memory Size: 512KB (512K x 8)
• Program Memory Type: FLASH
• Ram Size: 24K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 34x10b, D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 144-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

R
R
M
e
E
12.1 Count Source Protection Mode
3
. v
J
2
0
C
In count source protection mode, the on-chip oscillator clock is used as a count source for the watchdog
timer. The count source protection mode allows the on-chip oscillator clock to run continuously, maintain-
ing watchdog timer operation even if the program error occurs and the CPU clock stops running.
Follow the procedures below when using this mode.
(1) Set the PRC0 bit in the PRCR register to "1" (write to CM0 register enabled)
(2) Set the PRC1 bit in the PRCR register to "1" (write to PM2 register enabled)
(3) Set the CM06 bit in the CM0 register to "1" (reset when the watchdog timer overflows)
(4) Set the PM22 bit in the PM2 register to "1" (the on-chip oscillator clock as a count source of the watch-
(5) Set the PRC0 bit to "0" (write to CM0 register disabled)
(6) Set the PRC1 bit to "0" (write to PM2 register disabled)
(7) Write to the WDTS register (the watchdog timer starts counting)
1
9
0 .
8 /
B
The followings will occur when the PM22 bit is set to "1".
0
1
dog timer)
4
0
• The on-chip oscillator starts oscillating and the on-chip oscillator clock becomes a count source for
• Write to the CM10 bit in the CM1 register is disabled. (The bit setting remains unchanged even if set
3
• In wait mode or hold state, the watchdog timer continues running. However, the watchdog timer
G
J
6
u
the watchdog timer.
it to "1". The microcomputer does not enter stop mode.)
o r
interrupt cannot be used to exit wait mode.
0 -
. l
Watchdog timer cycle =
u
0
1
p
, 7
0
1
(
2
M
0
3
0
5
2
C
8 /
Page 134
, 4
M
3
2
C
f o
8 /
4
4
) T
9
5
Counter value of watchdog timer (32768)
On-chip oscillator clock
12. Watchdog Timer