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Chapter 19 Timebase Timer
4.Register
4. Register
4.1 TBCR: Timebase Timer Control Register
This register is used to set timebase timer interrupt control, reset/ standby operation option etc.
Note: Refer also to “Chapter 10 Standby (Page No.155)”.
• TBCR: Address 0482h (Access: Byte)
(Refer to “Meaning of Bit Attribute Symbols (Page No.10)” for the attributes.)
• Bit7: Timebase timer interrupt request flag
• An interrupt request is generated if the timebase timer interrupt request enable bit is “1”, and if the
timebase timer interrupt request flag is “1”.
• Bit6: Timebase timer interrupt request enable
• Bit5-3: Selecting the timebase timer interval time
• Be sure to set the interval time before an interrupt.
(Oscillation stability wait time used when returning to the stop caused by an interrupt)
• Bit2: Reserved bit
Writing does not affect the operation. The read value is indefinite.
7 6 5 4 3 2 1 0 bit
TBIF TBIE TBC2 TBC1 TBC0 --- SYNCR SYNCS
00XXXX00 Initial value
(INIT terminal input,
watchdog reset)
00XXXXXX Initial value
(the software reset)
R(RM1),W R/W R/W R/W R/W RX/WX RX/WX R/W Attribute
TBIF Operation
Read Write
0 With no interrupt request Flag is cleared
1With interrupt request
(The interval time set by the timebase timer
has elapsed) Writing does not affect operation
TBIE Operation
0 Disabling the timebase timer interrupt request
1 Enabling the timebase timer interrupt request
TBC2-TBC0 Interval time
Example
While the main clock operates
(4.0MHz, PLL8 multiply) While the subclock operates
(32.768kHz)
000 Φ ×211 64.0µs62.5ms
001 Φ ×212 128µs125ms
010 Φ ×213 256µs250ms
011 Φ ×222 131ms 128s
100 Φ ×223 262ms 256s
101 Φ ×224 524ms 512s
110 Φ ×225 1048ms 1024s
111 Φ ×226 2097ms 2048s