- 您现在的位置：买卖IC网 > PDF目录67761 > M34519M8-XXXFP 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO42 PDF资料下载
参数资料
| 型号： | M34519M8-XXXFP |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO42 |
| 封装： | 0.450 INCH, 0.80 MM PITCH, PLASTIC, SSOP-42 |
| 文件页数： | 81/138页 |
| 文件大小： | 1146K |
| 代理商： | M34519M8-XXXFP |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页当前第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页第108页第109页第110页第111页第112页第113页第114页第115页第116页第117页第118页第119页第120页第121页第122页第123页第124页第125页第126页第127页第128页第129页第130页第131页第132页第133页第134页第135页第136页第137页第138页
4519 Group
Rev.3.01
2005.06.15
page 45 of 160
REJ03B0007-0301
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 “000016,” 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. 34 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 cycle because the count source of watchdog timer
is the instruction clock.
FFFF16
000016
相关PDF资料 |
PDF描述 |
|---|---|
| M34519M6-XXXFP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO42 |
| M34553M8H-XXXFP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PQFP48 |
| M34553M4-XXXFP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PQFP48 |
| M34553G8HFP | 4-BIT, OTPROM, 6 MHz, MICROCONTROLLER, PQFP48 |
| M34553M4H-XXXFP | 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PQFP48 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| M34-52 | 制造商:GAMEWELL-FCI 制造商全称:GAMEWELL-FCI 功能描述:Three-Fold Fire Alarm Boxes and Transmitters |
| M34524EDFP | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34524M8-XXXFP | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER |
| M34524MC-XXXFP | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:4-BIT CISC SINGLE-CHIP MICROCOMPUTER 720 FAMILY / 4500 SERIES |
| M3452-C09K1 | 制造商:Bonitron 功能描述:OVERVOLTAGE BRAKING TRANSISTOR |
发布紧急采购，3分钟左右您将得到回复。