- 您现在的位置：买卖IC网 > PDF目录80460 > M37544M2-XXXSP 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP32 PDF资料下载
参数资料
| 型号： | M37544M2-XXXSP |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP32 |
| 封装： | 0.400 INCH, 1.78 MM PITCH, PLASTIC, SDIP-32 |
| 文件页数： | 60/70页 |
| 文件大小： | 645K |
| 代理商： | M37544M2-XXXSP |
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页当前第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
7544 Group
Rev.1.04
2004.06.08
page 61 of 66
REJ03B0012-0104Z
Termination of Unused Pins
1. Terminate unused pins
Perform the following wiring at the shortest possible distance (20
mm or less) from microcomputer pins.
(1) I/O ports
Set the I/O ports for the input mode and connect each pin to VCC
or VSS through each resistor of 1 k
to 10 k. The port which can
select a built-in pull-up resistor can also use the built-in pull-up re-
sistor.
When using the I/O ports as the output mode, open them at “L” or
“H”.
When opening them in the output mode, the input mode of the
initial status remains until the mode of the ports is switched over
to the output mode by the program after reset. Thus, the poten-
tial at these pins is undefined and the power source current may
increase in the input mode. With regard to an effects on the sys-
tem, thoroughly perform system evaluation on the user side.
Since the direction register setup may be changed because of a
program runaway or noise, set direction registers by program
periodically to increase the reliability of program.
2. Termination remarks
(1) I/O ports setting as input mode
[1] Do not open in the input mode.
<Reason>
The power source current may increase depending on the first-
stage circuit.
An effect due to noise may be easily produced as compared with
proper termination (1) shown on the above “1. Terminate unused
pins”.
[2] Do not connect to VCC or VSS directly.
<Reason>
If the direction register setup changes for the output mode be-
cause of a program runaway or noise, a short circuit may occur.
[3] Do not connect multiple ports in a lump to VCC or VSS through
a resistor.
<Reason>
If the direction register setup changes for the output mode be-
cause of a program runaway or noise, a short circuit may occur
between ports.
Notes on Interrupts
1. Change of relevant register settings
When not requiring for the interrupt occurrence synchronous with
the following case, take the sequence shown in Figure 5.
When switching external interrupt active edge
When switching interrupt sources of an interrupt vector address
where two or more interrupt sources are allocated
Fig. 5 Sequence of changing relevant register
<Reason>
When setting the followings, the interrupt request bit of the corre-
sponding interrupt may be set to “1”.
When switching external interrupt active edge
INT0 interrupt edge selection bit
(bit 0 of Interrupt edge selection register (address 3A16))
INT1 interrupt edge selection bit
(bit 1 of Interrupt edge selection register)
CNTR0 active edge switch bit
(bit 2 of timer X mode register (address 2B16))
CNTR1 active edge switch bit
(bit 6 of timer A mode register (address 1D16))
2. Check of interrupt request bit
When executing the BBC or BBS instruction to determine an in-
terrupt request bit immediately after this bit is set to “0”, take the
following sequence.
<Reason>
If the BBC or BBS instruction is executed immediately after an in-
terrupt request bit is cleared to “0”, the value of the interrupt
request bit before being cleared to “0” is read.
Set the corresponding interrupt enable bit to “0” (disabled) .
↓
Set the interrupt edge selection bit, active edge switch bit, or
the interrupt source selection bit.
↓
NOP (One or more instructions)
↓
Set the corresponding interrupt request bit to “0”
(no interrupt request issued).
↓
Set the corresponding interrupt enable bit to “1” (enabled).
Set the interrupt request bit to “0” (no interrupt issued)
↓
NOP (one or more instructions)
↓
Execute the BBC or BBS instruction
Fig. 6 Sequence of check of interrupt request bit
相关PDF资料 |
PDF描述 |
|---|---|
| MB90567PMC | 16-BIT, MROM, 16 MHz, MICROCONTROLLER, PQFP64 |
| M37221MAH-XXXSP | 8-BIT, MROM, 8.1 MHz, MICROCONTROLLER, PDIP42 |
| M38037M8-XXXHP | 8-BIT, MROM, 8.4 MHz, MICROCONTROLLER, PQFP64 |
| M38049FFFP | 8-BIT, FLASH, 8.4 MHz, MICROCONTROLLER, PQFP64 |
| M38049FFHSP | 8-BIT, FLASH, 8.4 MHz, MICROCONTROLLER, PDIP64 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| M37544RSS | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| M37545G1KP | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| M37545G2KP | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| M37545G4GP | 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER |
| M37545G4GP#U0 | 功能描述:MCU 2/5V 16K 32-LQFP QZ-ROM RoHS:是 类别:集成电路 (IC) >> 嵌入式 - 微控制器， 系列:740/38000 标准包装:250 系列:80C 核心处理器:8051 芯体尺寸:8-位 速度:16MHz 连通性:EBI/EMI，I²C，UART/USART 外围设备:POR，PWM，WDT 输入/输出数:40 程序存储器容量:- 程序存储器类型:ROMless EEPROM 大小:- RAM 容量:256 x 8 电压 - 电源 (Vcc/Vdd):4.5 V ~ 5.5 V 数据转换器:A/D 8x10b 振荡器型:内部 工作温度:-40°C ~ 85°C 封装/外壳:68-LCC（J 形引线） 包装:带卷 (TR) |
发布紧急采购，3分钟左右您将得到回复。