Clocked from se" />
參數(shù)資料
型號: ATMEGA164PA-MCHR
廠商: Atmel
文件頁數(shù): 112/160頁
文件大小: 0K
描述: MCU AVR 16KB FLASH 20MHZ 44-VQFN
產(chǎn)品培訓模塊: megaAVR Introduction
標準包裝: 1
系列: AVR® ATmega
核心處理器: AVR
芯體尺寸: 8-位
速度: 20MHz
連通性: I²C,SPI,UART/USART
外圍設(shè)備: 欠壓檢測/復位,POR,PWM,WDT
輸入/輸出數(shù): 32
程序存儲器容量: 16KB(8K x 16)
程序存儲器類型: 閃存
EEPROM 大小: 512 x 8
RAM 容量: 1K x 8
電壓 - 電源 (Vcc/Vdd): 1.8 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 ~ 85°C
封裝/外殼: 44-VQFN 裸露焊盤
包裝: 剪切帶 (CT)
其它名稱: ATMEGA164PA-MCHRCT
55
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
11.3
Watchdog Timer
11.3.1
Features
Clocked from separate On-chip Oscillator
Three 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
11.3.2
Overview
Atmel ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P has an Enhanced Watch-
dog Timer (WDT). The WDT is a timer counting cycles of a separate on-chip 128kHz 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.
Figure 11-7. Watchdog Timer.
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 always on (WDTON) fuse, if programmed, will force the Watchdog Timer to Sys-
tem Reset mode. With the fuse programmed the System Reset mode bit (WDE) and Interrupt
mode bit (WDIE) are locked to 1 and 0 respectively. To further ensure program security, altera-
tions to the Watchdog set-up must follow timed sequences. The sequence for clearing WDE and
changing time-out configuration is as follows:
128kHz
OSCILLATOR
OSC/2K
OSC/4K
OSC/8K
OSC/16K
OSC/32K
OSC/64K
OSC/128K
OSC/256K
OSC/512K
OSC/1024K
WDP0
WDP1
WDP2
WDP3
WATCHDOG
RESET
WDE
WDIF
WDIE
MCU RESET
INTERRUPT
相關(guān)PDF資料
PDF描述
SC16C654BIBS,551 IC UART QUAD W/FIFO 48-HVQFN
SC16C654BIBS,528 IC QUAD UART 64BYTE 48HVQFN
SCC2681AC1N40,112 IC UART DUAL 40-DIP
SC16IS760IBS,151 IC UART I2C/SPI 24-HVQFN
XR16C854CJ-F IC UART FIFO 128B QUAD 68PLCC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ATMEGA164PA-MN 功能描述:8位微控制器 -MCU AVR 16KB FL 512B EE 1KB SRAM 20MHz Grn 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
ATMEGA164PA-MNR 功能描述:8位微控制器 -MCU AVR 16KB FL 512B EE 1KB SRAM 20 MHZ GRN 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
ATMEGA164PA-MU 功能描述:8位微控制器 -MCU AVR 16KB 512B EE 20MHz 1KB SRAM 125c 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
ATMEGA164PA-MUR 功能描述:8位微控制器 -MCU AVR,16KB FLASH,20MHZ IND TEMP,8V 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
ATMEGA164PA-PU 功能描述:8位微控制器 -MCU AVR 16KB 512B EE 20MHz 1KB SRAM 125c 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