参数资料
型号: DS17285S-5+T&R
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: XO, clock
英文描述: 3V/5V Real-Time Clock
中文描述: 1 TIMER(S), REAL TIME CLOCK, PDSO24
封装: SO-24
文件页数: 16/38页
文件大小: 411K
代理商: DS17285S-5+T&R
DS17285/DS17287
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SYSTEM MAINTENANCE INTERRUPT (SMI) RECOVERY STACK
An SMI recovery register stack is located in the extended register bank, locations 4Eh and 4Fh. This
register stack, shown below, can be used by the BIOS to recover from an SMI occurring during an RTC
read or write.
The RTC address is latched on the falling edge of the ALE signal. Each time an RTC address is latched,
the register address stack is pushed. The stack is only four registers deep, holding the three previous RTC
addresses in addition to the current RTC address being accessed. The following waveform illustrates how
the BIOS could recover the RTC address when an SMI occurs.
1) The RTC address is latched.
2) An SMI is generated before an RTC read or write occurs.
3) RTC address 0Ah is latched and the address from 1 is pushed to the “RTC Address–1” stack location.
This step is necessary to change the bank select bit, DV0 = 1.
4) RTC address 4Eh is latched and the address from 1 is pushed to location 4Eh, “RTC Address–2”
while 0Ah is pushed to the “RTC Address–1” location. The data in this register, 4Eh, is the RTC
address lost due to the SMI.
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相关代理商/技术参数
参数描述
DS17285SN- 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:Real-Time Clocks
DS17285SN3 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:Real-Time Clocks
DS17285SN-3 功能描述:实时时钟 RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS17285SN-3+ 功能描述:实时时钟 3V/5V RTC K Multiplexed Kick-S RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 总线接口:I2C 日期格式:DW:DM:M:Y 时间格式:HH:MM:SS RTC 存储容量:64 B 电源电压-最大:5.5 V 电源电压-最小:1.8 V 最大工作温度:+ 85 C 最小工作温度: 安装风格:Through Hole 封装 / 箱体:PDIP-8 封装:Tube
DS17285SN5 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:Real-Time Clocks