M34286T2-CPE User’s Manual
2. Setup
R20UT0214EJ0200 Rev.2.00
Page 28 of 70
Sep 16, 2010
2.5 Watchdog Timer Initialization Cycle Check Pin
With this product, the watchdog function cannot be debugged.
However, the watchdog timer initialization cycle can be verified by observing the waveform at the check pin (WRST)
of the emulator.
(1) Check Pin WRST (TP3) on the Emulator
Figure 2.10 shows the location of the WRST (TP3) and GND (TP2).
J3
10
11
1
20
IC
2
2
SW
1
M
ADE
PA
C
T
EM
UL
A
T
O
R
SA
F
E
PO
W
E
R
PO
W
E
R
CL
O
C
K
RE
S
E
T
RU
N
ST
A
T
U
S
SY
S
T
E
M
S
T
AT
US
T
ARG
E
T
MA
D
E
IN
J
A
P
A
N
CO
M
P
A
C
T
E
M
U
L
A
T
O
R
PO
WE
R
5.
0V
US
B
M3
42
86
T2
-C
PE
Figure 2.10 Location of the check pin
IMPORTANT
Note on the Watchdog Timer Function:
•
With this emulator system, the watchdog timer function cannot be invalidated.
If an MCU reset occurs by the watchdog timer, the emulator will not operate properly. In this case,
perform a reset input from the emulator debugger or reset the emulator system.
Also, after a reset by the watchdog timer occurs, the problems below may appear in the emulator
debugger:
(1) Only information of address 0000h is displayed in the results of real-time trace.
(2) When a user program is forcibly stopped, the value of program counter is the same as when started.
(3) The software break and hardware break do not occur in the program.
While a user program is stopped, the WRST instruction is always executed in order not to cause a reset
by the watchdog timer.
