參數(shù)資料
型號: COP8SAB728N8
廠商: National Semiconductor
文件頁數(shù): 29/62頁
文件大?。?/td> 0K
描述: IC MCU OTP 8BIT 2K POR 28-DIP
標準包裝: 13
系列: COP8™ 8SA
核心處理器: COP8
芯體尺寸: 8-位
速度: 10MHz
連通性: Microwire/Plus(SPI)
外圍設(shè)備: POR,PWM,WDT
輸入/輸出數(shù): 24
程序存儲器容量: 2KB(2K x 8)
程序存儲器類型: OTP
RAM 容量: 128 x 8
電壓 - 電源 (Vcc/Vdd): 2.7 V ~ 5.5 V
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 28-DIP(0.600",15.24mm)
包裝: 管件
其它名稱: *COP8SAB728N8
10.0 WATCHDOG/Clock Monitor
The devices contain a user selectable WATCHDOG and
clock monitor. The following section is applicable only if
WATCHDOG feature has been selected in the ECON regis-
ter. The WATCHDOG is designed to detect the user program
getting stuck in infinite loops resulting in loss of program
control or “runaway” programs.
The WATCHDOG logic contains two separate service win-
dows. While the user programmable upper window selects
the WATCHDOG service time, the lower window provides
protection against an infinite program loop that contains the
WATCHDOG service instruction.
The COP8SAx devices provide the added feature of a soft-
ware trap that provides protection against stack overpops
and addressing locations outside valid user program space.
The Clock Monitor is used to detect the absence of a clock or
a very slow clock below a specified rate on the CKI pin.
The WATCHDOG consists of two independent logic blocks:
WD UPPER and WD LOWER. WD UPPER establishes the
upper limit on the service window and WD LOWER defines
the lower limit of the service window.
Servicing the WATCHDOG consists of writing a specific
value to a WATCHDOG Service Register named WDSVR
which is memory mapped in the RAM. This value is com-
posed of three fields, consisting of a 2-bit Window Select, a
5-bit Key Data field, and the 1-bit Clock Monitor Select field.
Table 6 shows the WDSVR register.
TABLE 6. WATCHDOG Service Register (WDSVR)
Window
Key Data
Clock
Select
Monitor
X
01100
Y
The lower limit of the service window is fixed at 256 instruc-
tion cycles. Bits 7 and 6 of the WDSVR register allow the
user to pick an upper limit of the service window.
Table 7 shows the four possible combinations of lower and
upper limits for the WATCHDOG service window. This flex-
ibility in choosing the WATCHDOG service window prevents
any undue burden on the user software.
Bits 5, 4, 3, 2 and 1 of the WDSVR register represent the
5-bit Key Data field. The key data is fixed at 01100. Bit 0 of
the WDSVR Register is the Clock Monitor Select bit.
TABLE 7. WATCHDOG Service Window Select
WDSVR
Clock
Service Window
Bit 7
Bit 6
Monitor
(Lower-Upper Limits)
0
x
2048–8k t
C Cycles
0
1
x
2048–16k t
C Cycles
1
0
x
2048–32k t
C Cycles
1
x
2048–64k t
C Cycles
x
0
Clock Monitor Disabled
x
1
Clock Monitor Enabled
10.1 CLOCK MONITOR
The Clock Monitor aboard the device can be selected or
deselected under program control. The Clock Monitor is
guaranteed not to reject the clock if the instruction cycle
clock (1/t
C) is greater or equal to 10 kHz. This equates to a
clock input rate on CKI of greater or equal to 100 kHz.
10.2 WATCHDOG/CLOCK MONITOR OPERATION
The WATCHDOG is enabled by bit 2 of the ECON register.
When this ECON bit is 0, the WATCHDOG is enabled and
pin G1 becomes the WATCHDOG output with a weak pullup.
The WATCHDOG and Clock Monitor are disabled during
reset. The device comes out of reset with the WATCHDOG
armed, the WATCHDOG Window Select bits (bits 6, 7 of the
WDSVR Register) set, and the Clock Monitor bit (bit 0 of the
WDSVR Register) enabled. Thus, a Clock Monitor error will
occur after coming out of reset, if the instruction cycle clock
frequency has not reached a minimum specified value, in-
cluding the case where the oscillator fails to start.
The WDSVR register can be written to only once after reset
and the key data (bits 5 through 1 of the WDSVR Register)
must match to be a valid write. This write to the WDSVR
register involves two irrevocable choices: (i) the selection of
the WATCHDOG service window (ii) enabling or disabling of
the Clock Monitor. Hence, the first write to WDSVR Register
involves selecting or deselecting the Clock Monitor, select
the WATCHDOG service window and match the WATCH-
DOG key data. Subsequent writes to the WDSVR register
will compare the value being written by the user to the
WATCHDOG service window value and the key data (bits 7
through 1) in the WDSVR Register.
Table 8 shows the se-
quence of events that can occur.
The user must service the WATCHDOG at least once before
the upper limit of the service window expires. The WATCH-
DOG may not be serviced more than once in every lower
limit of the service window. The user may service the
WATCHDOG as many times as wished in the time period
between the lower and upper limits of the service window.
The first write to the WDSVR Register is also counted as a
WATCHDOG service.
The WATCHDOG has an output pin associated with it. This
is the WDOUT pin, on pin 1 of the port G. WDOUT is active
low and must be externally connected to the RESET pin or to
some other external logic which handles WATCHDOG event.
The WDOUT pin has a weak pullup in the inactive state. This
pull-up is sufficient to serve as the connection to V
CC for
systems which use the internal Power On Reset. Upon
triggering the WATCHDOG, the logic will pull the WDOUT
(G1) pin low for an additional 16 t
C–32 tC cycles after the
signal level on WDOUT pin goes below the lower Schmitt
trigger threshold. After this delay, the device will stop forcing
the WDOUT output low. The WATCHDOG service window
will restart when the WDOUT pin goes high.
A WATCHDOG service while the WDOUT signal is active will
be ignored. The state of the WDOUT pin is not guaranteed
on reset, but if it powers up low then the WATCHDOG will
time out and WDOUT will go high.
The Clock Monitor forces the G1 pin low upon detecting a
clock frequency error. The Clock Monitor error will continue
until the clock frequency has reached the minimum specified
value, after which the G1 output will go high following 16
t
C–32 tC clock cycles. The Clock Monitor generates a con-
tinual Clock Monitor error if the oscillator fails to start, or fails
to reach the minimum specified frequency. The specification
for the Clock Monitor is as follows:
1/t
C > 10 kHz — No clock rejection.
1/t
C < 10 Hz — Guaranteed clock rejection.
COP8SA
Family
www.national.com
34
相關(guān)PDF資料
PDF描述
MC9S08DZ16ACLC IC MCU 16K FLASH 1K RAM 32-LQFP
PCF52274CLU120 MCU 32-BIT W/LCD TOUCH 176-LQFP
MC9S08DZ16CLF IC MCU 16K FLASH 1K RAM 48-LQFP
MK20DX128VLH5 IC ARM CORTEX MCU 128KB 64LQFP
MC9S08DN32CLF IC MCU 32K FLASH 1.5K RAM48-LQFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
COP8SAB728N9 功能描述:IC MCU OTP 8BIT 2K 28DIP RoHS:否 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:COP8™ 8SA 其它有關(guān)文件:STM32F101T8 View All Specifications 特色產(chǎn)品:STM32 32-bit Cortex MCUs 標準包裝:490 系列:STM32 F1 核心處理器:ARM? Cortex?-M3 芯體尺寸:32-位 速度:36MHz 連通性:I²C,IrDA,LIN,SPI,UART/USART 外圍設(shè)備:DMA,PDR,POR,PVD,PWM,溫度傳感器,WDT 輸入/輸出數(shù):26 程序存儲器容量:64KB(64K x 8) 程序存儲器類型:閃存 EEPROM 大小:- RAM 容量:10K x 8 電壓 - 電源 (Vcc/Vdd):2 V ~ 3.6 V 數(shù)據(jù)轉(zhuǎn)換器:A/D 10x12b 振蕩器型:內(nèi)部 工作溫度:-40°C ~ 85°C 封裝/外殼:36-VFQFN,36-VFQFPN 包裝:托盤 配用:497-10030-ND - STARTER KIT FOR STM32497-8853-ND - BOARD DEMO STM32 UNIV USB-UUSCIKSDKSTM32-PL-ND - KIT IAR KICKSTART STM32 CORTEXM3497-8512-ND - KIT STARTER FOR STM32F10XE MCU497-8505-ND - KIT STARTER FOR STM32F10XE MCU497-8304-ND - KIT STM32 MOTOR DRIVER BLDC497-6438-ND - BOARD EVALUTION FOR STM32 512K497-6289-ND - KIT PERFORMANCE STICK FOR STM32MCBSTM32UME-ND - BOARD EVAL MCBSTM32 + ULINK-MEMCBSTM32U-ND - BOARD EVAL MCBSTM32 + ULINK2更多... 其它名稱:497-9032STM32F101T8U6-ND
COP8SAB7SLB8 功能描述:IC MCU OTP 8BIT 2K 28LAMINATECSP RoHS:否 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:COP8™ 8SA 標準包裝:250 系列:56F8xxx 核心處理器:56800E 芯體尺寸:16-位 速度:60MHz 連通性:CAN,SCI,SPI 外圍設(shè)備:POR,PWM,溫度傳感器,WDT 輸入/輸出數(shù):21 程序存儲器容量:40KB(20K x 16) 程序存儲器類型:閃存 EEPROM 大小:- RAM 容量:6K x 16 電壓 - 電源 (Vcc/Vdd):2.25 V ~ 3.6 V 數(shù)據(jù)轉(zhuǎn)換器:A/D 6x12b 振蕩器型:內(nèi)部 工作溫度:-40°C ~ 125°C 封裝/外殼:48-LQFP 包裝:托盤 配用:MC56F8323EVME-ND - BOARD EVALUATION MC56F8323
COP8SAB7SLB9 功能描述:IC MCU OTP 8BIT 2K 28LAMINATECSP RoHS:否 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:COP8™ 8SA 標準包裝:250 系列:56F8xxx 核心處理器:56800E 芯體尺寸:16-位 速度:60MHz 連通性:CAN,SCI,SPI 外圍設(shè)備:POR,PWM,溫度傳感器,WDT 輸入/輸出數(shù):21 程序存儲器容量:40KB(20K x 16) 程序存儲器類型:閃存 EEPROM 大小:- RAM 容量:6K x 16 電壓 - 電源 (Vcc/Vdd):2.25 V ~ 3.6 V 數(shù)據(jù)轉(zhuǎn)換器:A/D 6x12b 振蕩器型:內(nèi)部 工作溫度:-40°C ~ 125°C 封裝/外殼:48-LQFP 包裝:托盤 配用:MC56F8323EVME-ND - BOARD EVALUATION MC56F8323
COP8SAC5 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAC7 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging