參數(shù)資料
型號: C8051F221
廠商: Silicon Laboratories Inc
文件頁數(shù): 141/146頁
文件大?。?/td> 0K
描述: IC 8051 MCU 8K FLASH 32LQFP
標準包裝: 250
系列: C8051F2xx
核心處理器: 8051
芯體尺寸: 8-位
速度: 25MHz
連通性: SPI,UART/USART
外圍設(shè)備: 欠壓檢測/復(fù)位,POR,WDT
輸入/輸出數(shù): 22
程序存儲器容量: 8KB(8K x 8)
程序存儲器類型: 閃存
RAM 容量: 256 x 8
電壓 - 電源 (Vcc/Vdd): 2.7 V ~ 3.6 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 22x8b
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 32-LQFP
包裝: 托盤
C8051F2xx
94
Rev. 1.6
Disable WDT
Writing 0xDE followed by 0xAD to the WDTCN register disables the WDT. The following code segment
illustrates disabling the WDT.
CLR
EA
; disable all interrupts
MOV
WDTCN,#0DEh
; disable watchdog timer
MOV
WDTCN,#0ADh
;
SETB
EA
; re-enable interrupts
The writes of 0xDE and 0xAD must occur within 4 clock cycles of each other, or the disable operation is
ignored. Interrupts should be disabled during this procedure to avoid delay between the two writes.
Disable WDT Lockout
Writing 0xFF to WDTCN locks out the disable feature. Once locked out, the disable operation is ignored
until the next system reset. Writing 0xFF does not enable or reset the watchdog timer. Applications alays
intending to use the watchdog should write 0xFF to WDTCN in their initialization code.
Setting WDT Interval
WDTCN.[2:0] control the watchdog timeout interval. The interval is given by the following equation:
43+WDTCN[2:0] x TSYSCLK , (where TSYSCLK is the system clock period).
For a 2.0 MHz system clock, this provides an interval range of 32msec to 524msec. WDTCN.7 must be
written as 0 when setting this interval. Reading WDTCN returns the programmed interval. WDTCN.[2:0] is
111b after a system reset.
SFR Definition 12.1. WDTCN: Watchdog Timer Control
Bits7–0: WDT Control
Writing 0xA5 both enables and reloads the WDT.
Writing 0xDE followed within 4 clocks by 0xAD disables the WDT.
Writing 0xFF locks out the disable feature.
Bit4:
Watchdog Status Bit (when Read)
Reading the WDTCN.[4] bit indicates the Watchdog Timer Status.
0: WDT is inactive
1: WDT is active
Bits2–0: Watchdog Timeout Interval Bits
The WDTCN.[2:0] bits set the Watchdog Timeout Interval. When writing these bits,
WDTCN.7 must be set to 0.
R/W
Reset Value
xxxxx111
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
SFR Address:
0xFF
相關(guān)PDF資料
PDF描述
C8051F220 IC 8051 MCU 8K FLASH 48TQFP
C8051F012 IC 8051 MCU 32K FLASH 32LQFP
PIC18LF6525-I/PT IC PIC MCU FLASH 24KX16 64TQFP
C8051F011 IC 8051 MCU 32K FLASH 48TQFP
C8051F010 IC 8051 MCU 32K FLASH 64TQFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
C8051F221-GQ 功能描述:8位微控制器 -MCU 8KB 8ADC 32P MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
C8051F221-GQR 功能描述:8位微控制器 -MCU 8KB 8ADC 32Pin MCU Tape and Reel RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
C8051F221R 功能描述:8位微控制器 -MCU T-8 32 Pin RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
C8051F226 功能描述:8位微控制器 -MCU 8KB 8ADC 1KRam RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
C8051F226DK 功能描述:開發(fā)板和工具包 - 8051 MCU DEVELOPMENT KIT W/ US POWER SUPPLY RoHS:否 制造商:Silicon Labs 產(chǎn)品:Development Kits 工具用于評估:C8051F960, Si7005 核心: 接口類型:USB 工作電源電壓: