- 您现在的位置：买卖IC网 > PDF目录370133 > 7534 (Renesas Technology Corp.) SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER PDF资料下载
参数资料
| 型号： | 7534 |
| 厂商： | Renesas Technology Corp. |
| 英文描述： | SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| 中文描述： | 单芯片8位CMOS微机 |
| 文件页数： | 33/55页 |
| 文件大小： | 610K |
| 代理商： | 7534 |
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页当前第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
7534 Group
Rev.2.00 Jun 21, 2004 page 33 of 54
REJ03B0099-0200Z
Watchdog Timer
The watchdog timer gives a means for returning to a reset status
when the program fails to run on its normal loop due to a runaway.
The watchdog timer consists of an 8-bit watchdog timer H and an 8-
bit watchdog timer L, being a 16-bit counter.
Standard operation of watchdog timer
The watchdog timer stops when the watchdog timer control register
(address 0039
16
) is not set after reset. Writing an optional value to
the watchdog timer control register (address 0039
16
) causes the
watchdog timer to start to count down. When the watchdog timer H
underflows, an internal reset occurs. Accordingly, it is programmed
that the watchdog timer control register (address 0039
16
) can be set
before an underflow occurs.
When the watchdog timer control register (address 0039
16
) is read,
the values of the high-order 6-bit of the watchdog timer H, STP in-
struction disable bit and watchdog timer H count source selection bit
are read.
Initial value of watchdog timer
By a reset or writing to the watchdog timer control register (address
0039
16
), the watchdog timer H is set to “FF
16
” and the watchdog
timer L is set to “FF
16
”.
Operation of watchdog timer H count source selection bit
A watchdog timer H count source can be selected by bit 7 of the
watchdog timer control register (address 0039
16
). When this bit is
“0”, the count source becomes a watchdog timer L underflow signal.
The detection time is 174.763 ms at f(X
IN
)=6 MHz.
When this bit is “1”, the count source becomes f(X
IN
)/16. In this
case, the detection time is 683 μs at f(X
IN
)=6 MHz.
This bit is cleared to “0” after reset.
Operation of STP instruction disable bit
When the watchdog timer is in operation, the STP instruction can be
disabled by bit 6 of the watchdog timer control register (address
0039
16
).
When this bit is “0”, the STP instruction is enabled.
When this bit is “1”, the STP instruction is disabled, and an internal
reset occurs if the STP instruction is executed.
Once this bit is set to “1”, it cannot be changed to “0” by program.
This bit is cleared to “0” after reset.
Fig. 38 Block diagram of watchdog timer
Fig. 39 Structure of watchdog timer control register
X
IN
Data bus
“0”
“1”
Watchdog timer H count
source selection bit
1/16
Reset
circuit
STP Instruction Disable Bit
STP Instruction
Watchdog timer H (8)
Write “FF
16
” to the
watchdog timer
control register
Internal reset
RESET
Watchdog timer L (8)
Write “FF
16
” to the
watchdog timer
control register
Watchdog timer control register(address 0039
16
)
WDTCON
Watchdog timer H (read-only for high-order 6-bit)
STP instruction disable bit
0 : STP instruction enabled
1 : STP instruction disabled
Watchdog timer H count source selection bit
0 : Watchdog timer L underflow
1 : f(X
IN
)/16
b7 b0
相关PDF资料 |
PDF描述 |
|---|---|
| 7548 | SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| 7549 | SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| 75HQ | SCHOTTKY RECTIFIER |
| 75HQ030 | SCHOTTKY RECTIFIER |
| 75HQ035 | SCHOTTKY RECTIFIER |
相关代理商/技术参数 |
参数描述 |
|---|---|
| 7534_06 | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:8-BIT SINGLE-CHIP MICROCOMPUTER |
| 75340 | 功能描述:BIT MICRO HEX SYST4 4.0MM 28MM RoHS:否 类别:工具 >> 螺钉和螺母驱动器 - 刀片和位 系列:系统 4 标准包装:1 系列:TorqueVario™ 类型:十字槽刀片 尺寸:#2 长度:7.48"（190mm） 特点:绝缘达 10,000V 重量:0.07 磅（31.75g） |
| 753-40.4M-A | 制造商:OSCILENT 制造商全称:Oscilent Corporation 功能描述:Ceramic Trap For TV/VCR |
| 753-40.7M-A | 制造商:OSCILENT 制造商全称:Oscilent Corporation 功能描述:Ceramic Trap For TV/VCR |
| 753-402 | 制造商:WAGO Innovative Connections 功能描述:4DI 24V DC 3,0ms |
发布紧急采购，3分钟左右您将得到回复。