參數(shù)資料
型號(hào): MC68HC05P9ACDW
廠商: FREESCALE SEMICONDUCTOR INC
元件分類: 微控制器/微處理器
英文描述: 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDSO28
封裝: SOIC-28
文件頁數(shù): 138/158頁
文件大小: 3885K
代理商: MC68HC05P9ACDW
COP
80
COP
Introduction
The purpose of the computer operating properly (COP) watchdog is to
reset the MCU in case of software failure. Software that is operating
properly periodically services the COP watchdog and prevents the reset
from occurring. The COP watchdog function is selectable with a mask
option.
Operation
COP Watchdog
Timeout
The COP watchdog is a 16-bit counter that generates a reset if allowed
to time out. Periodically clearing the counter starts a new timeout period
and prevents the COP from resetting the MCU. A COP watchdog
timeout indicates that the software is not executing instructions in the
correct sequence.
NOTE:
The internal clock drives the COP watchdog. Therefore, the COP
watchdog cannot generate a reset for errors that cause the internal clock
to stop.
The COP watchdog also depends on a power supply voltage at or above
a minimum specification and is not guaranteed to protect against
brownout. For information about brownout protection, see the Resets
COP Watchdog
Timeout Period
Use the following formula to calculate the COP timeout period:
where
COP Timeout Period
131 072 cycles
,
f
BUS
---------------------------------------
=
f
BUS
crystal frequency
2
---------------------------------------------
=
6-cop0cop
F
re
e
sc
a
le
S
e
m
ic
o
n
d
u
c
to
r,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
c
..
.
相關(guān)PDF資料
PDF描述
MC68HC05P9AVDW 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDSO28
MC68HC05P9AMDW 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDSO28
MC68HC05P9ACP 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP28
MC68HC05P9DWR2 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDSO28
MC68HC05RC18P 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP28
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC68HC05P9ACP 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05P9ADW 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05P9AMDW 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05P9AMP 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05P9AP 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit