HD6433640 HITACHI [Hitachi Semiconductor], HD6433640 Datasheet - Page 283

• Manufacturer Part Number: HD6433640
• Description: H8/3644 Series Hardware Manual
• Manufacturer: HITACHI [Hitachi Semiconductor]

Bit 5—Bit 4 Write Inhibit (B4WI): Bit 5 controls the writing of data to bit 4 in TCSRW.
This bit is always read as 1. Data written to this bit is not stored.
Bit 5: B4WI
0
1
Bit 4—Timer Control/Status Register W Write Enable (TCSRWE): Bit 4 controls the writing
of data to TCSRW bits 2 and 0.
Bit 4: TCSRWE
0
1
Bit 3—Bit 2 Write Inhibit (B2WI): Bit 3 controls the writing of data to bit 2 in TCSRW.
This bit is always read as 1. Data written to this bit is not stored.
Bit 3: B2WI
0
1
Bit 2—Watchdog Timer On (WDON): Bit 2 enables watchdog timer operation.
Counting starts when this bit is set to 1, and stops when this bit is cleared to 0.
Bit 2: WDON
0
1
Description
Bit 4 is write-enabled
Bit 4 is write-protected
Description
Data cannot be written to bits 2 and 0
Data can be written to bits 2 and 0
Description
Bit 2 is write-enabled
Bit 2 is write-protected
Description
Watchdog timer operation is disabled
Clearing conditions:
Reset, or when TCSRWE = 1 and 0 is written in both B2WI and WDON
Watchdog timer operation is enabled
Setting conditions:
When TCSRWE = 1 and 0 is written in B2WI and 1 is written in WDON
(initial value)
(initial value)
(initial value)
(initial value)
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