参数资料
型号: ST72325J4B6
厂商: STMICROELECTRONICS
元件分类: 微控制器/微处理器
英文描述: MICROCONTROLLER, PDIP42
封装: 0.600 INCH, ROHS COMPLIANT, PLASTIC, DIP-42
文件页数: 140/197页
文件大小: 3582K
代理商: ST72325J4B6
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页第108页第109页第110页第111页第112页第113页第114页第115页第116页第117页第118页第119页第120页第121页第122页第123页第124页第125页第126页第127页第128页第129页第130页第131页第132页第133页第134页第135页第136页第137页第138页第139页当前第140页第141页第142页第143页第144页第145页第146页第147页第148页第149页第150页第151页第152页第153页第154页第155页第156页第157页第158页第159页第160页第161页第162页第163页第164页第165页第166页第167页第168页第169页第170页第171页第172页第173页第174页第175页第176页第177页第178页第179页第180页第181页第182页第183页第184页第185页第186页第187页第188页第189页第190页第191页第192页第193页第194页第195页第196页第197页
ST72325xx
47/197
POWER SAVING MODES (Cont’d)
8.4 ACTIVE-HALT AND HALT MODES
ACTIVE-HALT and HALT modes are the two low-
est power consumption modes of the MCU. They
are both entered by executing the ‘HALT’ instruc-
tion. The decision to enter either in ACTIVE-HALT
or HALT mode is given by the MCC/RTC interrupt
enable flag (OIE bit in MCCSR register).
8.4.1 ACTIVE-HALT MODE
ACTIVE-HALT mode is the lowest power con-
sumption mode of the MCU with a real time clock
available. It is entered by executing the ‘HALT’ in-
struction when the OIE bit of the Main Clock Con-
troller Status register (MCCSR) is set (see section
10.2 on page 61 for more details on the MCCSR
register).
The MCU can exit ACTIVE-HALT mode on recep-
tion of an external interrupt, MCC/RTC interrupt or
a RESET. When exiting ACTIVE-HALT mode by
means of an interrupt, no 256 or 4096 CPU cycle
delay occurs. The CPU resumes operation by
servicing the interrupt or by fetching the reset vec-
tor which woke it up (see Figure 30).
When entering ACTIVE-HALT mode, the I[1:0] bits
in the CC register are forced to ‘10b’ to enable in-
terrupts. Therefore, if an interrupt is pending, the
MCU wakes up immediately.
In ACTIVE-HALT mode, only the main oscillator
and its associated counter (MCC/RTC) are run-
ning to keep a wake-up time base. All other periph-
erals are not clocked except those which get their
clock supply from another clock generator (such
as external or auxiliary oscillator).
The safeguard against staying locked in ACTIVE-
HALT mode is provided by the oscillator interrupt.
Note: As soon as the interrupt capability of one of
the oscillators is selected (MCCSR.OIE bit set),
entering ACTIVE-HALT mode while the Watchdog
is active does not generate a RESET.
This means that the device cannot spend more
than a defined delay in this power saving mode.
CAUTION: When exiting ACTIVE-HALT mode fol-
lowing an MCC/RTC interrupt, OIE bit of MCCSR
register must not be cleared before tDELAY after
the interrupt occurs (tDELAY = 256 or 4096 tCPU de-
lay depending on option byte). Otherwise, the ST7
enters HALT mode for the remaining tDELAY peri-
od.
Figure 29. ACTIVE-HALT Timing Overview
Figure 30. ACTIVE-HALT Mode Flow-chart
Notes:
1. This delay occurs only if the MCU exits ACTIVE-
HALT mode by means of a RESET.
2. Peripheral clocked with an external clock source
can still be active.
3. Before servicing an interrupt, the CC register is
pushed on the stack. The I[1:0] bits of the CC reg-
ister are set to the current software priority level of
the interrupt routine and restored when the CC
register is popped.
MCCSR
OIE bit
Power Saving Mode entered when HALT
instruction is executed
0
HALT mode
1
ACTIVE-HALT mode
HALT
RUN
256 OR 4096 CPU
CYCLE DELAY 1)
RESET
OR
INTERRUPT
HALT
INSTRUCTION
FETCH
VECTOR
ACTIVE
[MCCSR.OIE=1]
HALT INSTRUCTION
RESET
Y
N
Y
CPU
OSCILLATOR
PERIPHERALS 2)
I[1:0] BITS
ON
OFF
10
OFF
FETCH RESET VECTOR
OR SERVICE INTERRUPT
CPU
OSCILLATOR
PERIPHERALS
I[1:0] BITS
ON
OFF
XX 3)
ON
CPU
OSCILLATOR
PERIPHERALS
I[1:0] BITS
ON
XX 3)
ON
256OR 4096CPU CLOCK
CYCLE DELAY
(MCCSR.OIE=1)
INTERRUPT
相关PDF资料
PDF描述
ST72325K6T3 MICROCONTROLLER, QFP32
ST72325C9T3 MICROCONTROLLER, QFP48
ST72325C9T6 MICROCONTROLLER, QFP48
ST72325J7T6 MICROCONTROLLER, QFP44
ST72325K6B3 MICROCONTROLLER, PDIP32
相关代理商/技术参数
参数描述
ST72325J4T3 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-bit MCU with 16 to 60K Flash/ROM, ADC, CSS, 5 timers, SPI, SCI, I2C interface
ST72325J4T6 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-bit MCU with 16 to 60K Flash/ROM, ADC, CSS, 5 timers, SPI, SCI, I2C interface
ST72325J6B3 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-bit MCU with 16 to 60K Flash/ROM, ADC, CSS, 5 timers, SPI, SCI, I2C interface
ST72325J6B6 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-bit MCU with 16 to 60K Flash/ROM, ADC, CSS, 5 timers, SPI, SCI, I2C interface
ST72325J6T3 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-bit MCU with 16 to 60K Flash/ROM, ADC, CSS, 5 timers, SPI, SCI, I2C interface