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2. CPU Core
2.3 System clock controller
TMP89FM42
RA001
2.3.5.2
Dual-clock mode
The gear clock (fcgck) and the low-frequency clock (fs) are used for the operation in the dual-clock
mode.
The main system clock (fm) is generated from the gear clock (fcgck) in the NORMAL2 or IDLE2
mode, and generated from the clock that is a quarter of the low-frequency clock (fs) in the SLOW1/2 or
SLEEP0/1 mode. Therefore, the machine cycle time is 1/fcgck [s] in the NORMAL2 or IDLE2 mode and
is 4/fs [s] in the SLOW1/2 or SLEEP0/1 mode.
P03 (XTIN) and P04 (XTOUT) are used as the low-frequency clock oscillation circuit pins. (These pins
cannot be used as I/O ports in the dual-clock mode.)
The operation of the TLCS-870/C1 Series becomes the single-clock mode after reset release. To operate
it in the dual-clock mode, allow the low-frequency clock to oscillate at the beginning of the program.
(1)
NORMAL2 mode
In this mode, the CPU core operates using the gear clock (fcgck), and the peripheral circuits oper-
ate using the gear clock (fcgck) or the clock that is a quarter of the low-frequency clock (fs).
(2)
SLOW2 mode
In this mode, the CPU core and the peripheral circuits operate using the clock that is a quarter of
the low-frequency clock (fs).
In the SLOW mode, some peripheral circuits become the same as the states when a reset is
released. For operations of the peripheral circuits in the SLOW mode, refer to the section of each
peripheral circuit.
Set SYSCR2<SYSCK> to switch the operation mode from NORMAL2 to SLOW2 or from
SLOW2 to NORMAL2.
In the SLOW2 mode, outputs of the prescaler and stages 1 to 8 of the divider stop.
(3)
SLOW1 mode
In this mode, the high-frequency clock oscillation circuit stops operation and the CPU core and the
peripheral circuits operate using the clock that is a quarter of the low-frequency clock (fs).
This mode requires less power to operate the high-frequency clock oscillation circuit than in the
SLOW2 mode.
In the SLOW mode, some peripheral circuits become the same as the states when a reset is
released. For operations of the peripheral circuits in the SLOW mode, refer to the section of each
peripheral circuit.
Set SYSCR2<XEN> to switch the operation between the SLOW1 and SLOW2 modes.
In the SLOW1 or SLEEP1 mode, outputs of the prescaler and stages 1 to 8 of the divider stop.
(4)
IDLE2 mode
In this mode, the CPU and the watchdog timer stop and the peripheral circuits operate using the
gear clock (fcgck) or the clock that is a quarter of the low-frequency clock (fs).
The IDLE2 mode can be activated and released in the same way as for the IDLE1 mode. The oper-
ation returns to the NORMAL2 mode after this mode is released.
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: ......