參數(shù)資料
型號: M34508G4FP
元件分類: 微控制器/微處理器
英文描述: 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDSO20
封裝: 5.30 X12.60 MM, 1.27 MM PITCH, PLASTIC, SOP-20
文件頁數(shù): 78/106頁
文件大小: 1059K
代理商: M34508G4FP
4508 Group
Rev.1.03
2009.07.27
page 71 of 140
REJ03B0148-0103
Fig. 72 Watchdog timer by software
<The main routine>
Assigns a single word of RAM to a software watchdog timer
(SWDT) and writes the initial value N in the SWDT once at each
execution of the main routine. The initial value N should satisfy the
following condition:
N+1 ≥ (Counts of interrupt processing executed in each main rou-
tine)
As the main routine execution cycle may change because of an in-
terrupt processing or others, the initial value N should have a
margin.
Watches the operation of the interrupt processing routine by com-
paring the SWDT contents with counts of interrupt processing after
the initial value N has been set.
Detects that the interrupt processing routine has failed and deter-
mines to branch to the program initialization routine for recovery
processing in the following case:
If the SWDT contents do not change after interrupt processing.
<The interrupt processing routine>
Decrements the SWDT contents by 1 at each interrupt processing.
Determines that the main routine operates normally when the
SWDT contents are reset to the initial value N at almost fixed
cycles (at the fixed interrupt processing count).
Detects that the main routine has failed and determines to branch
to the program initialization routine for recovery processing in the
following case:
If the SWDT contents are not initialized to the initial value N but
continued to decrement and if they reach 0 or less.
Main routine
(SWDT)← N
EI
Main processing
(SWDT)
Interrupt processing
routine errors
N
Interrupt processing routine
(SWDT) ← (SWDT)—1
Interrupt processing
(SWDT)
Main routine
errors
>0
≤0
RTI
Return
=N?
≤0?
≠N
相關PDF資料
PDF描述
M34518M2-XXXFP 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PQFP32
M34518M4-XXXSP 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDIP32
M34518E8FP 4-BIT, OTPROM, 6 MHz, MICROCONTROLLER, PQFP32
M34518M2-XXXSP 4-BIT, MROM, 6 MHz, MICROCONTROLLER, PDIP32
M34518E8SP 4-BIT, OTPROM, 6 MHz, MICROCONTROLLER, PDIP32
相關代理商/技術參數(shù)
參數(shù)描述
M34508G4GP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
M34508G4GP#U0 功能描述:MCU 2/5V 4096 QZROM PB-FREE 20-S RoHS:是 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:720/4500 標準包裝:300 系列:78K0R/Ix3 核心處理器:78K/0R 芯體尺寸:16-位 速度:40MHz 連通性:3 線 SIO,I²C,LIN,UART/USART 外圍設備:DMA,LVD,POR,PWM,WDT 輸入/輸出數(shù):27 程序存儲器容量:16KB(16K x 8) 程序存儲器類型:閃存 EEPROM 大小:- RAM 容量:1K x 8 電壓 - 電源 (Vcc/Vdd):2.7 V ~ 5.5 V 數(shù)據(jù)轉換器:A/D 8x10b 振蕩器型:內部 工作溫度:-40°C ~ 85°C 封裝/外殼:38-SSOP 包裝:托盤
M34508G4GP(#UO) 制造商:Renesas Electronics Corporation 功能描述:
M34508G4HFP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
M34508G4HGP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER