- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄370838 > M34514M8-759FP (Mitsubishi Electric Corporation) SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER PDF資料下載
參數(shù)資料
| 型號(hào)： | M34514M8-759FP |
| 廠商： | Mitsubishi Electric Corporation |
| 英文描述： | SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| 中文描述： | 單芯片4位微機(jī)的CMOS |
| 文件頁數(shù)： | 33/106頁 |
| 文件大?。?/td> | 1304K |
| 代理商： | M34514M8-759FP |
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頁第30頁第31頁第32頁當(dāng)前第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頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁第81頁第82頁第83頁第84頁第85頁第86頁第87頁第88頁第89頁第90頁第91頁第92頁第93頁第94頁第95頁第96頁第97頁第98頁第99頁第100頁第101頁第102頁第103頁第104頁第105頁第106頁
33
4513/4514 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
PRELIMINARY
Notice: This is not a final specification.
change.
Some parametric limits are subject to
WATCHDOG TIMER
Watchdog timer provides a method to reset the system when a pro-
gram runs wild. Watchdog timer consists of a 16-bit timer (WDT),
watchdog timer enable flag (WEF), and watchdog timer flags
(WDF1, WDF2).
The timer WDT downcounts the instruction clocks as the count
source. The underflow signal is generated when the count value
reaches “0000
16
.” This underflow signal can be used as the timer 2
count source.
When the WRST instruction is executed after system is released
from reset, the WEF flag is set to “1”. At this time, the watchdog
timer starts operating.
When the count value of timer WDT reaches “BFFF
16
” or “3FFF
16
,”
the WDF1 flag is set to “1.” If the WRST instruction is never ex-
ecuted while timer WDT counts 32767, WDF2 flag is set to “1,” and
the RESET pin outputs “L” level to reset the microcomputer. Ex-
ecute the WRST instruction at each period of 32766 machine cycle
or less by software when using watchdog timer to keep the micro-
computer operating normally.
To prevent the WDT stopping in the event of misoperation, WEF
flag is designed not to initialize once the WRST instruction has
been executed. Note also that, if the WRST instruction is never ex-
ecuted, the watchdog timer does not start.
Fig. 20 Watchdog timer function
The contents of WEF, WDF1 and WDF2 flags and timer WDT are
initialized at the RAM back-up mode.
If WDF2 flag is set to “1” at the same time that the microcomputer
enters the RAM back-up state, system reset may be performed.
When using the watchdog timer and the RAM back-up mode, ini-
tialize the WDF1 flag with the WRST instruction just before the
microcomputer enters the RAM back-up state (refer to Figure 21)
Fig. 21 Program example to enter the RAM back-up mode
when using the watchdog timer
WRST ; WDF1 flag reset
POF
EPOF ; POF instruction enabled
(RAM back-up state)
Oscillation
stop
FFFF
16
0000
16
3FFF
16
BFFF
16
The value of timer (WDT)
WDF1 flag
WDF2 flag
WRST
instruction
executed
RESET pin output
System reset
WRST
instruction
executed
WEF flag
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| M34513E4FP | SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34513E4SP | SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34513E8FP | SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34514E8FP | SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34513E4 | SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| M34514M8-XXXFP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34518E8FP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34518E8SP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34518M2-XXXFP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34518M2-XXXSP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。