M37702E6BFS Renesas Electronics America, M37702E6BFS Datasheet - Page 256

• Manufacturer Part Number: M37702E6BFS
• Description: EPROM MCU/8BIT CMOS EMULATION CH
• Manufacturer: Renesas Electronics America

Specifications of M37702E6BFS

• Accessory Type: Emulator EPROM MCU
• For Use With/related Products: 7702
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

WATCHDOG TIMER
9.3 Precautions when using watchdog timer
9.3 Precautions when using watchdog timer
1. When a dummy data is written to address 60
2. When the STP instruction (refer to “Chapter 10. STOP MODE”) is executed, Watchdog timer stops.
3. To stop Watchdog timer in Hold state, the count source which is actually counted by Watchdog timer is
Fig. 9.3.1 Watchdog timer’s count source
9–8
simultaneously performed. Accordingly, when the user does not want to change a value of the watchdog
timer frequency select bit (bit 0 at address 61
writing to address 60
When Watchdog timer is used to detect the program runaway, select “STP instruction disable” with mask
option.
the logical AND product of two signals. One is the inverted signal input from the HOLD pin, and the other
is the count source (f
duration which is shorter than 1 cycle of the count source (Note), counting by Watchdog timer can be
performed. (Refer to Figure 9.3.1.)
Note: It is selected with the watchdog timer frequency select bit.
counted by Watchdog timer
HOLD pin input signal
Count source actually
Clock f
32
or f
16
32
512
.
or f
512
)(Note). Accordingly, when the HOLD pin’s input signal level changes in a
7702/7703 Group User’s Manual
16
16
), write the previous value to the bit simultaneously with
with the 16-bit data length, writing to address 61
_____
When HOLD pin’s input signal level
changes in duration which is shorter
than 1 cycle of f
_____
32
or f
512
16
is