参数资料
型号: ST72C314N4TC
厂商: STMICROELECTRONICS
元件分类: 微控制器/微处理器
英文描述: 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PQFP64
封装: 14 X 14 MM, ROHS COMPLIANT, TQFP-64
文件页数: 98/150页
文件大小: 3530K
代理商: ST72C314N4TC
ST72334xx-Auto, ST72314xx-Auto, ST72124Jx-Auto
51/150
WATCHDOG TIMER (Cont’d)
The application program must write in the CR reg-
ister at regular intervals during normal operation to
prevent an MCU reset. The value to be stored in
the CR register must be between FFh and C0h
– The WDGA bit is set (watchdog enabled)
– The T6 bit is set to prevent generating an imme-
diate reset
– The T[5:0] bits contain the number of increments
which represents the time delay before the
watchdog produces a reset.
Table 12.Watchdog Timing (fCPU = 8 MHz)
Notes: Following a reset, the watchdog is disa-
bled. Once activated it cannot be disabled, except
by a reset.
The T6 bit can be used to generate a software re-
set (the WDGA bit is set and the T6 bit is cleared).
If the watchdog is activated, the HALT instruction
will generate a Reset.
13.1.4 Hardware Watchdog Option
If Hardware Watchdog is selected by option byte,
the watchdog is always active and the WDGA bit in
the CR is not used.
Refer to the device-specific Option Byte descrip-
tion.
13.1.5 Low Power Modes
13.1.6 Interrupts
None.
13.1.7 Register Description
CONTROL REGISTER (CR)
Read/Write
Reset Value: 0111 1111 (7Fh)
Bit 7 = WDGA Activation bit.
This bit is set by software and only cleared by
hardware after a reset. When WDGA = 1, the
watchdog can generate a reset.
0: Watchdog disabled
1: Watchdog enabled
Note: This bit is not used if the hardware watch-
dog option is enabled by option byte.
Bit 6:0 = T[6:0] 7-bit timer (MSB to LSB).
These bits contain the decremented value. A reset
is produced when it rolls over from 40h to 3Fh (T6
becomes cleared).
STATUS REGISTER (SR)
Read/Write
Reset Value*: 0000 0000 (00h)
Bit 0 = WDOGF Watchdog flag.
This bit is set by a watchdog reset and cleared by
software or a power on/off reset. This bit is useful
for distinguishing power/on off or external reset
and watchdog reset.
0: No Watchdog reset occurred
1: Watchdog reset occurred
* Only by software and power on/off reset
Note: This register is not used in versions without
LVD Reset.
CR Register
initial value
WDG timeout period
(ms)
Max
FFh
98.304
Min
C0h
1.536
Mode
Description
WAIT
No effect on Watchdog.
HALT
Immediate reset generation as soon as the
HALT instruction is executed if the Watch-
dog is activated (WDGA bit is set).
7
0
WDGA
T6
T5
T4
T3
T2
T1
T0
7
0
-
WDOGF
相关PDF资料
PDF描述
ST72124J2TC/XXX 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP44
ST72334J4TB/XXX 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP44
ST72C314J2TC 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PQFP44
ST72314N4TA/XXX 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP64
ST72314N4TB/XXX 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP64
相关代理商/技术参数
参数描述
ST72C334J2B6 功能描述:8位微控制器 -MCU Flash 8K SPI/SCI RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ST72C334J2T6 功能描述:8位微控制器 -MCU Flash 8K SPI/SCI RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ST72C334J4B6 功能描述:8位微控制器 -MCU Flash 16K SPI/SCI RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ST72C334J4T6 功能描述:8位微控制器 -MCU Flash 16K SPI/SCI RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ST72C334J4T6/TR 制造商:STMicroelectronics 功能描述: