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Chapter 19 Timebase Timer
4.Register
• Bit1: Enabling the synchronous reset operation
• Ordinary operation reset: Immediately resets the operation initialization when the operation initialization
reset (RST) request is generated.
Synchronous reset: Resets the operation initialization after all accesses to the bus have stopped.
• Bit0: Synchronous standby operation enable
4.2 CTBR: Timebase Counter Clear Register
This register is used to initialize the timebase counter.
• CTBR: Address 0483h (Access: Byte)
(Refer to “Meaning of Bit Attribute Symbols (Page No.10)” for the attributes)
• Continuously writing “A5H”,“5AH”in the timebase counter clear register clears the timebase counter
immediately after writing “5AH”. (All bits are“0”)
There is no time restrictions between “A5H”and “5AH”, but if “A5H”is written followed by the one other than
“5AH”, you should write “A5H” again. If not, the timebase counter cannot be cleared even if“5AH” is written.
• The read value is indefinite.
• Clearing the timebase counter using the timebase counter clear register temporarily modifies the relevant
items shown below.
• Oscillation stability wait interval
• Watchdog timer period
• Timebase timer period
SYNCR Operation
0 Ordinary reset operation
1 Synchronous reset operation enable
SYNCS Operation
0 Ordinary reset operation (In this product, any setting is prohibited)
1 Synchronous standby operation enable (Be sure to set before making the transition to standby)
76543210 bit
D7 D6 D5 D4 D3 D2 D1 D0
X X X X X X X X Initial value
RX/W RX/W RX/W RX/W RX/W RX/W RX/W RX/W Attribute