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12. Time Base Timer (TBT)
12.1 Time Base Timer
TMP89FM42
RA001
Note 3: TBTCR<TBTCK> should be set when TBTCR<TBTEN> is "0".
Note 4: When SYSCR1<DV9CK> is "1" in the NORMAL 1/2 or IDLE1/2 mode, the interrupt request is subject to some fluctuations
to synchronize fs and fcgck.
Note 5: Bits 7 to 4 of TBTCR are read as "0".
12.1.3 Functions
Select the source clock frequency for the time base timer by TBTCR<TBTCK>. TBTCR<TBTCK> should
be changed when TBTCR<TBTEN> is "0". Otherwise, the INTTBT interrupt request is generated at unex-
pected timing.
Setting TBTCR<TBTEN> to "1" causes interrupt request signals to occur at the falling edge of the source
clock. When TBTCR<TBTEN> is cleared to "0", no interrupt request signal will occur.
When the operation is changed to the STOP mode, TBTCR<TBTEN> is cleared to "0".
The source clock of the time base timer operates regardless of the TBTCR<TBTEN> value.
A time base timer interrupt is generated at the first falling edge of the source clock after a time base timer
interrupt request is enabled. Therefore, the period from when the time TBTCR<TBTEN> is set to "1" to the
time when the first interrupt request occurs is shorter than the frequency period set at TBTCR<TBTCK>.
Figure 12-2 Time Base Timer Interrupt
When the operation is changed from NORMAL mode to SLOW mode or from SLOW mode to NORMAL
mode, The interrupt request will not occur at the expected timing due to synchronization of the gear clock
(fcgck) and the low-frequency clock (fs). It is recommened that the operation mode is changed when
TBTCR<TBTEN> is "0".
Table 12-1 Time Base Timer Interrupt Frequency (Example: when fcgck = 10.0 MHz and fs =
32.768 kHz)
TBTCK
Time base timer interrupt frequency [Hz]
NORMAL1/2, IDLE1/2 mode
NORMAL1/2, IDLE1/2 mode
SLOW1/2, SLEEP1 mode
DV9CK = 0
DV9CK = 1
000
2.38
1
1
001
9.54
4
4
010
305.18
128
Reserved
011
1220.70
512
Reserved
100
2441.41
1024
Reserved
101
4882.81
2048
Reserved
110
9765.63
4096
Reserved
111
39062.5
Reserved
Reserved
Example: Set the time base timer interrupt frequency to fcgck/2
15
[Hz] and enable interrupts.
Source clock
Time base timer enable
Interrupt period
TBTCR<TBTEN>
INTTBT interrupt
request
Содержание TLCS-870/C1 Series
Страница 1: ...8 Bit Microcontroller TLCS 870 C1 Series TMP89FM42 查询TMP89FM42供应商 捷多邦 专业PCB打样工厂 24小时加急出货 ...
Страница 3: ...Revision History Date Revision 2007 10 25 1 First Release 2007 11 3 2 Contents Revised ...
Страница 4: ......
Страница 14: ......
Страница 18: ...1 3 Block Diagram TMP89FM42 1 3 Block Diagram Figure 1 2 Block Diagram ...
Страница 22: ...1 4 Pin Names and Functions TMP89FM42 ...
Страница 60: ...2 CPU Core 2 5 Revision History TMP89FM42 ...
Страница 76: ...3 Interrupt Control Circuit 3 8 Revision History TMP89FM42 ...
Страница 86: ...4 External Interrupt control circuit 4 3 Function TMP89FM42 ...
Страница 102: ...7 Voltage Detection Circuit 7 5 Revision History TMP89FM42 ...
Страница 126: ...8 I O Ports 8 3 I O Port Registers TMP89FM42 Note 2 i 0 to 1 ...
Страница 136: ...8 I O Ports 8 5 Revision History TMP89FM42 ...
Страница 142: ...9 Special Function Registers 9 3 SFR3 0x0E40 to 0x0EFF TMP89FM42 ...
Страница 146: ...10 Low Power Consumption Function for Peripherals TMP89FM42 ...
Страница 149: ...TMP89FM42 11 3 Revision History Rev Description RA001 Deleted SLEEP2 description ...
Страница 150: ...11 Divider Output DVO 11 3 Revision History TMP89FM42 ...
Страница 220: ...15 Real Time Clock RTC 15 4 Real Time Clock Operation TMP89FM42 ...
Страница 250: ...16 Asynchronous Serial Interface UART 16 15 Revision History TMP89FM42 ...
Страница 302: ...18 Serial Bus Interface SBI 18 7 Revision History TMP89FM42 ...
Страница 336: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 Note 1 Make sure that you set the C register to 0x00 LD FLSCR2 0xD5 ...
Страница 338: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 ...
Страница 384: ...22 Serial PROM Mode 22 15 Revision History TMP89FM42 ...
Страница 388: ...24 Input Output Circuit 24 1 Control Pins TMP89FM42 ...
Страница 404: ...25 Electrical Characteristics 25 11 Revision History TMP89FM42 ...
Страница 406: ...26 Package Dimensions TMP89FM42 ...
Страница 408: ......