- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄67761 > M34502M4-XXXFP 4-BIT, MROM, MICROCONTROLLER, PDSO24 PDF資料下載
參數(shù)資料
| 型號(hào)： | M34502M4-XXXFP |
| 元件分類： | 微控制器/微處理器 |
| 英文描述： | 4-BIT, MROM, MICROCONTROLLER, PDSO24 |
| 封裝： | 5.30 X 10.10 MM, 0.80 MM PITCH, PLASTIC, SSOP-24 |
| 文件頁(yè)數(shù)： | 39/116頁(yè) |
| 文件大?。?/td> | 896K |
| 代理商： | M34502M4-XXXFP |
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)當(dāng)前第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)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)第105頁(yè)第106頁(yè)第107頁(yè)第108頁(yè)第109頁(yè)第110頁(yè)第111頁(yè)第112頁(yè)第113頁(yè)第114頁(yè)第115頁(yè)第116頁(yè)
4502 Group
Rev.3.01
2005.02.02
page 29 of 112
REJ03B0105-0301
WATCHDOG TIMER
Watchdog timer provides a method to reset the system when a pro-
gram run-away occurs. Watchdog timer consists of timer
WDT(16-bit binary counter), watchdog timer enable flag (WEF),
and watchdog timer flags (WDF1, WDF2).
The timer WDT downcounts the instruction clocks as the count
source from “FFFF16” after system is released from reset.
After the count is started, when the timer WDT underflow occurs
(after the count value of timer WDT reaches “FFFF16,” the next
count pulse is input), the WDF1 flag is set to “1.”
If the WRST instruction is never executed until the timer WDT un-
derflow occurs (until timer WDT counts 65534), WDF2 flag is set to
“1,” and the RESET pin outputs “L” level to reset the microcom-
puter.
Execute the WRST instruction at each period of 65534 machine
cycle or less by software when using watchdog timer to keep the
microcomputer operating normally.
When the WEF flag is set to “1” after system is released from reset,
the watchdog timer function is valid.
When the DWDT instruction and the WRST instruction are ex-
ecuted continuously, the WEF flag is cleared to “0” and the
watchdog timer function is invalid.
The WEF flag is set to "1" at system reset or RAM back-up mode.
The WRST instruction has the skip function. When the WRST in-
struction is executed while the WDF1 flag is “1”, the WDF1 flag is
cleared to “0” and the next instruction is skipped.
When the WRST instruction is executed while the WDF1 flag is “0”,
the next instruction is not skipped.
The skip function of the WRST instruction can be used even when
the watchdog timer function is invalid.
Fig. 25 Watchdog timer function
65534 count
(Note)
Value of 16-bit timer (WDT)
WDF1 flag
WRST instruction
executed
(skip executed)
RESET pin output
WDF2 flag
System reset
Reset
released
After system is released from reset (= after program is started), timer WDT starts count down.
When timer WDT underflow occurs, WDF1 flag is set to “1.”
When the WRST instruction is executed, WDF1 flag is cleared to “0,” the next instruction is skipped.
When timer WDT underflow occurs while WDF1 flag is “1,” WDF2 flag is set to “1” and the
watchdog reset signal is output.
The output transistor of RESET pin is turned “ON” by the watchdog reset signal and system reset is
executed.
Note: The number of count is equal to the number of machine cycle because the count source of watchdog timer
is the instruction clock.
FFFF16
000016
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| M34502M2-XXXFP | 4-BIT, MROM, MICROCONTROLLER, PDSO24 |
| M34508G4GP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO20 |
| M34508G4H-XXXFP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO20 |
| M34508G4-XXXFP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO20 |
| M34508G4HGP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO20 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| M34506E4 | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34506E4FP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34506M2 | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34506M2-XXXFP | 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:4-BIT CISC SINGLE-CHIP MICROCOMPUTER 4500 SERIES |
| M34506M4 | 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(gòu)，3分鐘左右您將得到回復(fù)。