- 您現在的位置：買賣IC網 > PDF目錄382369 > P89LPC922 (NXP Semiconductors N.V.) MINIATURE POWER RELAY PDF資料下載
參數資料
| 型號： | P89LPC922 |
| 廠商： | NXP Semiconductors N.V. |
| 英文描述： | MINIATURE POWER RELAY |
| 中文描述： | 8位微控制器兩個小時80C51的核心2鍵盤/ 4 KB的/ 8 KB的3伏的低功耗Flash 256 - RAM的字節數據 |
| 文件頁數： | 30/45頁 |
| 文件大小： | 877K |
| 代理商： | P89LPC922 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁當前第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁
Philips Semiconductors
P89LPC920/921/922
8-bit microcontrollers with two-clock 80C51 core
Product data
Rev. 06 — 21 November 2003
30 of 45
9397 750 12285
Koninklijke Philips Electronics N.V. 2003. All rights reserved.
8.22 Watchdog timer
The Watchdog timer causes a system reset when it underflows as a result of a failure
to feed the timer prior to the timer reaching its terminal count. It consists of a
programmable 12-bit prescaler, and an 8-bit down counter. The down counter is
decremented by a tap taken from the prescaler. The clock source for the prescaler is
either the PCLK or the nominal 400 kHz Watchdog oscillator. The Watchdog timer
can only be reset by a power-on reset. When the watchdog feature is disabled, it can
be used as an interval timer and may generate an interrupt.
Figure 11
shows the
Watchdog timer in watchdog mode. Feeding the watchdog requires a two-byte
sequence. If PCLK is selected as the watchdog clock and the CPU is powered-down,
the watchdog is disabled. The Watchdog timer has a time-out period that ranges from
a few
μ
s to a few seconds. Please refer to the P89LPC920/921/922User’s Manual for
more details.
8.23 Additional features
8.23.1
Software reset
The SRST bit in AUXR1 gives software the opportunity to reset the processor
completely, as if an external reset or watchdog reset had occurred. Care should be
taken when writing to AUXR1 to avoid accidental software resets.
8.23.2
Dual data pointers
The dual Data Pointers (DPTR) provides two different Data Pointers to specify the
address used with certain instructions. The DPS bit in the AUXR1 register selects
one of the two Data Pointers. Bit 2 of AUXR1 is permanently wired as a logic ‘0’ so
that the DPS bit may be toggled (thereby switching Data Pointers) simply by
incrementing the AUXR1 register, without the possibility of inadvertently altering other
bits in the register.
(1) Watchdog reset can also be caused by an invalid feed sequence, or by writing to WDCON not immediately followed by a
feed sequence.
Fig 11. Watchdog timer in watchdog mode (WDTE = ‘1’).
PRE2
PRE1
PRE0
–
–
WDRUN
WDTOF
WDCLK
WDCON (A7H)
CONTROL REGISTER
PRESCALER
002aaa423
SHADOW
REGISTER
FOR WDCON
8-BIT DOWN
COUNTER
WDL (C1H)
Watchdog
oscillator
PCLK
÷
32
MOV WFEED1, #0A5H
MOV WFEED2, #05AH
RESET
see note (1)
相關PDF資料 |
PDF描述 |
|---|---|
| P89LPC920 | 8-bit microcontrollers with two-clock 80C51 core 2 kB/4 kB/8 kB 3 V low-power Flash with 256-byte data RAM |
| P89LPC931 | 8-bit microcontrollers with two-clock 80C51 core 4 kB/8 kB 3 V Flash with 256-byte data RAM |
| P8C15416Y-12 | IC-8-BIT CMOS CPU |
| P903 | |
| P90C101ABA | 16-Bit Microcontroller |
相關代理商/技術參數 |
參數描述 |
|---|---|
| P89LPC9221FDH,512 | 功能描述:8位微控制器 -MCU 80C51 8K FL 256B RAM RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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 |
| P89LPC9221FDH,518 | 功能描述:8位微控制器 -MCU 8B MCU 80C51 2/4/8KB 3V FL 256B RAM RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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 |
| P89LPC9221FN | 功能描述:8位微控制器 -MCU 80C51 8K FL 256B RAM RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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 |
| P89LPC9221FN,112 | 功能描述:8位微控制器 -MCU 8K FL/256B RAM/I2C/UART/DIP20 RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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 |
| P89LPC9222A1 | 制造商:PHILIPS 制造商全稱:NXP Semiconductors 功能描述:8-bit microcontroller with accelerated two-clock 80C51 core 2 kB/4 kB/8 kB 3 V byte-erasable flash with 8-bit ADC |
發布緊急采購，3分鐘左右您將得到回復。