参数资料
型号: MIC74BQS
厂商: Micrel Inc
文件页数: 7/18页
文件大小: 0K
描述: IC I/O EXPANDER I2C 8B 16QSOP
标准包装: 98
接口: I²C,SM 总线
输入/输出数: 8
中断输出:
电源电压: 2.7 V ~ 3.6 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 16-SSOP(0.154",3.90mm 宽)
供应商设备封装: 16-QSOP
包装: 管件
Micrel, Inc.
MIC74
October 2006
15
M9999-101006
The act of reading STATUS clears it in preparation for
detecting future events. The status bits corresponding to
I/O’s configured as outputs or corresponding to P[7:4]
when in fan mode will not be set by state changes on
these pins. It is always good practice, however, for the
interrupt service routine to mask the value obtained
when reading STATUS to eliminate any bits, output or
otherwise, that are not of immediate concern. This will
help avoid problems if software changes are made in the
future.
The process for writing output data is straight-forward—
simply write the desired bit pattern to DATA. Special
precautions may be required, however, when changing
output data in an interrupt driven system. See the
discussion below under “Writing to the Data Register.”
Read STATUS to
determine source
Read alert
response address
Interrupts
pending
?
No
Yes
Is
Sx set
?
No
Yes
Interrupt Service
Routine
Return from ISR
Service function x
Is
interrupt
from
MIC74
Yes
No
Service other devices
Is
Sm set
?
No
Yes
Service function m
Is
Sn set
?
No
Yes
Service function n
Figure 11: Interrupt Service Routine Using the ARA
Writing To The Data Register
Multiple software routines may use the various output
bits available on the MIC74 to control individual functions
such as power switches, LED’s, etc. These various
functions may be handled by independent software
routines which must manipulate individual output bits
without regard for other bits. Care must be taken to
insure that these various software routines do not
interfere with each other when modifying output data.
The recommended procedure for changing isolated
output bits is as follows:
1. Read DATA
2. Set desired bits by ORing the value read from
DATA with an appropriate mask value
3. Clear desired bits by ANDing the value read
from DATA with an appropriate mask value
4. Write the result back to DATA
A functionally equivalent alternative to this procedure is
to keep an image of the data register in software. Any
independent routines would make changes to this image
using the procedure above and then call a routine that
actually writes the new image to DATA. Interrupts would
be disabled briefly while DATA is being modified.
Read
STATUS
Is
Sx set
?
No
Yes
Polled
I.S.R.
Service function x
Is
STATUS
h
?
Yes
No
Is
Sm set
?
No
Yes
Service function m
Is
Sn set
?
No
Yes
Service function n
Service other devices
Return from ISR
Figure 12: Interrupt Service Routine Without ARA
相关PDF资料
PDF描述
EXPANDIO-USB-PT-FS IC I/O EXPANDER USB 32B 44TQFP
MAX7300ATL+ IC I/O EXPANDER 2WIRE 40TQFN
MAX7300ATL+T IC I/O EXPANDER 2WIRE 40TQFN
MAX7300AAX+T IC I/O EXPANDER I2C 28B 36SSOP
PCA9698DGG,518 IC I/O EXPANDER I2C 40B 56TSSOP
相关代理商/技术参数
参数描述
MIC74BQS TR 功能描述:IC I/O EXPANDER I2C 8B 16QSOP RoHS:否 类别:集成电路 (IC) >> 接口 - I/O 扩展器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:74 系列:- 接口:I²C,JTAG 输入/输出数:9 中断输出:无 频率 - 时钟:400kHz 电源电压:2.7 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:20-TSSOP(0.173",4.40mm 宽) 供应商设备封装:20-TSSOP 包装:管件 包括:EEPROM
MIC74BWM 制造商:Rochester Electronics LLC 功能描述:- Bulk
MIC74YQS 功能描述:接口-I/O扩展器 2-Wire Serial I/O Expander & Fan Controller, QSOP-16 - Lead Free RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel
MIC74YQS TR 功能描述:接口-I/O扩展器 2-Wire Serial I/O Expander & Fan Controller, QSOP-17 - Lead Free RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel
MIC79050 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:Simple Lithium-Ion Battery Charger Preliminary Information