參數(shù)資料
型號(hào): AT89S2051-24PC
廠商: ATMEL CORP
元件分類: 微控制器/微處理器
英文描述: 8-bit Microcontroller with 2K/4K Bytes Flash
中文描述: 8-BIT, FLASH, 24 MHz, MICROCONTROLLER, PDIP20
封裝: 0.300 INCH, MS-001AD, PLASTIC, DIP-20
文件頁數(shù): 45/46頁
文件大小: 1051K
代理商: AT89S2051-24PC
8
3390D–MICRO–3/07
AT89S2051/S4051
10. Reset
During reset, all I/O Registers are set to their initial values, the port pins are weakly pulled to
V
CC, and the program starts execution from the Reset Vector, 0000H. The AT89S2051/S4051
has three sources of reset: power-on reset, brown-out reset, and external reset.
10.1
Power-On Reset
A Power-On Reset (POR) is generated by an on-chip detection circuit. The detection level is
nominally 1.4V. The POR is activated whenever V
CC is below the detection level. The POR cir-
cuit can be used to trigger the start-up reset or to detect a supply voltage failure in devices
without a brown-out detector. The POR circuit ensures that the device is reset from power-on.
When V
CC reaches the Power-on Reset threshold voltage, the Pierce Oscillator is enabled (if the
XTAL Oscillator Bypass fuse is OFF). Only after V
CC has also reached the BOD (brown-out
detection) level (see Section 10.2 ”Brown-out Reset”), the BOD delay counter starts measuring a
2-ms delay after which the Internal Reset is deasserted and the microcontroller starts executing.
The built-in 2-ms delay allows the V
CC voltage to reach the minimum 2.7V level before execut-
ing, thus guaranteeing the maximum operating clock frequency. The POR signal is activated
again, without any delay, when V
CC falls below the POR threshold level. A Power-On Reset (i.e.
a cold reset) will set the POF flag in PCON. Refer to Figure 10-1 for details on the POR/BOD
behavior.
Figure 10-1. Power-up and Brown-out Detection Sequence
POR
POR Level 1.4V
BOD Level 2.3V
Min V
CC Level 2.7V
XTAL1
BOD
Internal
RESET
t
V
CC
t
POR
(2 ms)
t
POR
(2 ms)
t
POR
(2 ms)
2.4V
1.2V
0
相關(guān)PDF資料
PDF描述
AT89S2051-24PI 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S2051-24SC 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S2051-24SI 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S2051-24PU 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S2051-24SU 8-bit Microcontroller with 2K/4K Bytes Flash
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AT89S2051-24PU 功能描述:8位微控制器 -MCU 2K FLSH 24MHZ 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(shí)鐘頻率:50 MHz 程序存儲(chǔ)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
AT89S2051-24SU 功能描述:8位微控制器 -MCU 2K FLASH 24MHZ SOIC 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(shí)鐘頻率:50 MHz 程序存儲(chǔ)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
AT89S2051W-16PI 功能描述:8位微控制器 -MCU Microcontroller 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(shí)鐘頻率:50 MHz 程序存儲(chǔ)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
AT89S2051W-16SI 功能描述:8位微控制器 -MCU Microcontroller 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(shí)鐘頻率:50 MHz 程序存儲(chǔ)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
AT89S4051-24PU 功能描述:8位微控制器 -MCU 4K FLASH 24MHZ 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(shí)鐘頻率:50 MHz 程序存儲(chǔ)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