SAH-C515 SIEMENS [Siemens Semiconductor Group], SAH-C515 Datasheet - Page 131

• Manufacturer Part Number: SAH-C515
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

8.1.5 WDT Control and Status Flags
The watchdog timer is controlled by two control flags (located in SFR IEN0 and IEN1) and one
status flags (located in SFR IP0).
Special Function Register IEN0 (Address A8 H )
Special Function Register IEN1 (Address B8 H )
Special Function Register IP0 (Address A9 H )
Bit
WDT
SWDT
WDTS
Semiconductor Group
Bit No.
A9 H
A8 H
B8 H
The shaded bits are not used for fail save control.
EXEN2 SWDT
MSB
EAL
AF
BF
7
–
H
H
WDTS
WDT
AE
BE
6
H
H
Function
Watchdog timer refresh flag.
Set to initiate a refresh of the watchdog timer. Must be set directly
before SWDT is set to prevent an unintentional refresh of the
watchdog timer. WDT is reset by hardware two processor cycles
after it has been set.
Watchdog timer start/refresh flag.
Set to activate the watchdog timer. When directly set after setting
WDT, a watchdog timer refresh/reset is performed. Bit SDWT is reset
by hardware two processor cycles after it has been set.
Watchdog timer status flag.
Set by hardware when a watchdog Timer reset occured. Can be
cleared and set by software.
IP0.5
ET2
EX6
AD
BD
5
H
H
IP0.4
EX5
ES
AC
BC
4
H
H
8-3
IP0.3
ET1
EX4
AB
BB
3
H
H
IP0.2
EX1
EX3
AA
BA
2
H
H
IP0.1
EX2
ET0
A9
B9
1
Fail Safe Mechanisms
H
H
Reset Value : X0000000 B
EADC
IP0.0
LSB
EX0
A8
B8
0
H
H
Reset Value : 00 H
Reset Value : 00 H
IEN0
IEN1
IP0
C515