參數(shù)資料
型號: AT90PWM1-16MUR
廠商: Atmel
文件頁數(shù): 43/90頁
文件大?。?/td> 0K
描述: MCU AVR 8K ISP FLASH 16MHZ 32QFN
產(chǎn)品培訓(xùn)模塊: megaAVR Introduction
標準包裝: 1
系列: AVR® 90PWM 照明
核心處理器: AVR
芯體尺寸: 8-位
速度: 16MHz
連通性: SPI
外圍設(shè)備: 欠壓檢測/復(fù)位,POR,PWM,WDT
輸入/輸出數(shù): 19
程序存儲器容量: 8KB(8K x 8)
程序存儲器類型: 閃存
EEPROM 大?。?/td> 512 x 8
RAM 容量: 512 x 8
電壓 - 電源 (Vcc/Vdd): 2.7 V ~ 5.5 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 8x10b
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 105°C
封裝/外殼: 32-VQFN 裸露焊盤
包裝: 剪切帶 (CT)
其它名稱: AT90PWM1-16MURCT
48
4378C–AVR–09/08
AT90PWM1
9.2
Watchdog Timer
AT90PWM1 has an Enhanced Watchdog Timer (WDT). The main features are:
Clocked from separate On-chip Oscillator
3 Operating modes
– Interrupt
– System Reset
– Interrupt and System Reset
Selectable Time-out period from 16ms to 8s
Possible Hardware fuse Watchdog always on (WDTON) for fail-safe mode
Figure 9-7.
Watchdog Timer
The Watchdog Timer (WDT) is a timer counting cycles of a separate on-chip 128 kHz oscillator.
The WDT gives an interrupt or a system reset when the counter reaches a given time-out value.
In normal operation mode, it is required that the system uses the WDR - Watchdog Timer Reset
- instruction to restart the counter before the time-out value is reached. If the system doesn't
restart the counter, an interrupt or system reset will be issued.
In Interrupt mode, the WDT gives an interrupt when the timer expires. This interrupt can be used
to wake the device from sleep-modes, and also as a general system timer. One example is to
limit the maximum time allowed for certain operations, giving an interrupt when the operation
has run longer than expected. In System Reset mode, the WDT gives a reset when the timer
expires. This is typically used to prevent system hang-up in case of runaway code. The third
mode, Interrupt and System Reset mode, combines the other two modes by first giving an inter-
rupt and then switch to System Reset mode. This mode will for instance allow a safe shutdown
by saving critical parameters before a system reset.
The “Watchdog Timer Always On” (WDTON) fuse, if programmed, will force the Watchdog Timer
to System Reset mode. With the fuse programmed the System Reset mode bit (WDE) and Inter-
rupt mode bit (WDIE) are locked to 1 and 0 respectively. To further ensure program security,
alterations to the Watchdog set-up must follow timed sequences. The sequence for clearing
WDE and changing time-out configuration is as follows:
1.
In the same operation, write a logic one to the Watchdog change enable bit (WDCE) and
WDE. A logic one must be written to WDE regardless of the previous value of the WDE
bit.
2.
Within the next four clock cycles, write the WDE and Watchdog prescaler bits (WDP) as
desired, but with the WDCE bit cleared. This must be done in one operation.
128 KHz
OSCILLATOR
MCU RESET
INTERRUPT
WDIE
WDIF
OSC/2K
OSC/4K
OSC/8K
WDP3
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參數(shù)描述
AT90PWM1-16SE 制造商:Atmel Corporation 功能描述:
AT90PWM1-16SU 功能描述:8位微控制器 -MCU AVR 8Kflash 2PSC No DALI 16MHz 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(fēng)格:SMD/SMT
AT90PWM161-16MN 功能描述:8位微控制器 -MCU 16 MHz, QFN, 105oC, Green, 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(fēng)格:SMD/SMT
AT90PWM161-16MNR 功能描述:8位微控制器 -MCU 16 MHz, QFN, 105oC, Green, T&R 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(fēng)格:SMD/SMT
AT90PWM161-16SN 功能描述:8位微控制器 -MCU 16 MHz, SOIC, 105oC, Green 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(fēng)格:SMD/SMT