- 您現(xiàn)在的位置：買(mǎi)賣(mài)IC網(wǎng) > PDF目錄373539 > T89C51RD2-SMSCM (TEMIC SEMICONDUCTORS) 0 to 40 MHz Flash Programmable 8-bit Microcontroller PDF資料下載
參數(shù)資料
| 型號(hào)： | T89C51RD2-SMSCM |
| 廠商： | TEMIC SEMICONDUCTORS |
| 元件分類(lèi)： | 微控制器/微處理器 |
| 英文描述： | 0 to 40 MHz Flash Programmable 8-bit Microcontroller |
| 中文描述： | 8-BIT, FLASH, 40 MHz, MICROCONTROLLER, PQCC68 |
| 封裝： | PLASTIC, LCC-68 |
| 文件頁(yè)數(shù)： | 46/104頁(yè) |
| 文件大?。?/td> | 798K |
| 代理商： | T89C51RD2-SMSCM |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)當(dāng)前第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)第89頁(yè)第90頁(yè)第91頁(yè)第92頁(yè)第93頁(yè)第94頁(yè)第95頁(yè)第96頁(yè)第97頁(yè)第98頁(yè)第99頁(yè)第100頁(yè)第101頁(yè)第102頁(yè)第103頁(yè)第104頁(yè)
46
T89C51RD2
4243G
–
8051
–
05/03
Hardware Watchdog
Timer
The WDT is intended as a recovery method in situations where the CPU may be sub-
jected to software upset. The WDT consists of a 14-bit counter and the WatchDog Timer
ReSeT (WDTRST) SFR. The WDT is by default disabled from exiting reset. To enable
the WDT, user must write 01EH and 0E1H in sequence to the WDTRST, SFR location
0A6H. When WDT is enabled, it will increment every machine cycle while the oscillator
is running and there is no way to disable the WDT except through reset (either hardware
reset or WDT overflow reset). When WDT overflows, it will drive an output RESET HIGH
pulse at the RST-pin.
Using the WDT
To enable the WDT, user must write 01EH and 0E1H in sequence to the WDTRST, SFR
location 0A6H. When WDT is enabled, the user needs to service it by writing to 01EH
and 0E1H to WDTRST to avoid WDT overflow. The 14-bit counter overflows when it
reaches 16383 (3FFFH) and this will reset the device. When WDT is enabled, it will
increment every machine cycle while the oscillator is running. This means the user must
reset the WDT at least every 16383 machine cycle. To reset the WDT the user must
write 01EH and 0E1H to WDTRST. WDTRST is a write only register. The WDT counter
cannot be read or written. When WDT overflows, it will generate an output RESET pulse
at the RST-pin. The RESET pulse duration is 96 x T
OSC
, where T
OSC
= 1/F
OSC
. To
make the best use of the WDT, it should be serviced in those sections of code that will
periodically be executed within the time required to prevent a WDT reset.
To have a more powerful WDT, a 2
7
counter has been added to extend the Time-out
capability, ranking from 16ms to 2s @ F
OSC
= 12MHz. To manage this feature, refer to
WDTPRG register description, Table 29. (SFR0A7h).
Table 28.
WDTRST Register
WDTRST Address (0A6h)
Write only, this SFR is used to reset/enable the WDT by writing 01EH then 0E1H in
sequence.
Table 29.
WDTPRG Register
WDTPRG Address (0A7h)
7
6
5
4
7
6
5
4
3
2
1
Reset value
X
X
X
X
X
X
X
3
2
1
0
T4
T3
T2
T1
T0
S2
S1
S0
Bit
Number
Bit
Mnemonic
Description
7
T4
Reserved
The value read from this bit is undeterminated. Do not try to set this bit..
6
T3
5
T2
4
T1
3
T0
2
S2
WDT Time-out select bit 2
1
S1
WDT Time-out select bit 1
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| T89C51RD2-3CSCL | 0 to 40 MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-3CSCM | 0 to 40 MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-3CSIL | 0 to 40 MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-3CSIM | 0 to 40 MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-DDVCM | 0 to 40 MHz Flash Programmable 8-bit Microcontroller |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| T89C51RD2-SMSC-M | 制造商:ATMEL 制造商全稱(chēng):ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-SMSIL | 制造商:ATMEL 制造商全稱(chēng):ATMEL Corporation 功能描述:0 to 40 MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-SMSI-L | 制造商:ATMEL 制造商全稱(chēng):ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller |
| T89C51RD2-SMSIM | 功能描述:IC MICRO CTRL 64K FLASH 68PLCC RoHS:否 類(lèi)別:集成電路 (IC) >> 嵌入式 - 微控制器， 系列:89C 標(biāo)準(zhǔn)包裝:9 系列:87C 核心處理器:8051 芯體尺寸:8-位 速度:40/20MHz 連通性:UART/USART 外圍設(shè)備:POR，WDT 輸入/輸出數(shù):32 程序存儲(chǔ)器容量:32KB（32K x 8） 程序存儲(chǔ)器類(lèi)型:OTP EEPROM 大小:- RAM 容量:256 x 8 電壓 - 電源 (Vcc/Vdd):4.5 V ~ 5.5 V 數(shù)據(jù)轉(zhuǎn)換器:- 振蕩器型:內(nèi)部 工作溫度:0°C ~ 70°C 封裝/外殼:40-DIP（0.600"，15.24mm） 包裝:管件 |
| T89C51RD2-SMSI-M | 制造商:ATMEL 制造商全稱(chēng):ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。