参数资料
型号: DS1685S-3
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: Timer or RTC
英文描述: 1 TIMER(S), REAL TIME CLOCK, PDSO24
封装: 0.300 INCH, SOP-24
文件页数: 7/34页
文件大小: 455K
代理商: DS1685S-3
DS1685/DS1687 3V/5V Real-Time Clocks
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NV RAM—RTC
The 242 general-purpose NV RAM bytes are not dedicated to any special function within the DS1685/DS1687.
They can be used by the application program as nonvolatile memory and are fully available during the update
cycle.
The user RAM is divided into two separate memory banks. When the bank 0 is selected, the 14 RTC registers and
114 bytes of user RAM are accessible. When bank 1 is selected, an additional 128 bytes of user RAM are
accessible through the extended RAM address and data registers.
INTERRUPT CONTROL
The DS1685/DS1687 includes six separate, fully automatic sources of interrupt for a processor:
1) Alarm Interrupt
2) Periodic Interrupt
3) Update-Ended Interrupt
4) Wake-Up Interrupt
5) Kickstart Interrupt
6) RAM Clear Interrupt
The conditions that generate each of these independent interrupt conditions are described in detail in other
sections of this text. This section describes the overall control of the interrupts.
The application software can select which interrupts, if any, are to be used. There are a total of 6 bits, including 3
bits in Register B and 3 bits in Extended Register 4B, that enable the interrupts. The extended register locations
are described later. Writing a logic 1 to an interrupt-enable bit permits that interrupt to be initiated when the event
occurs. A logic 0 in the interrupt enable bit prohibits the IRQ pin from being asserted from that interrupt condition. If
an interrupt flag is already set when an interrupt is enabled, IRQ is immediately set at an active level, even though
the event initiating the interrupt condition might have occurred much earlier. As a result, there are cases where the
software should clear these earlier generated interrupts before first enabling new interrupts.
When an interrupt event occurs, the relating flag bit is set to a logic 1 in Register C or in Extended Register 4A.
These flag bits are set regardless of the setting of the corresponding enable bit located either in Register B or in
Extended Register 4B. The flag bits can be used in a polling mode without enabling the corresponding enable bits.
However, care should be taken when using the flag bits of Register C as they are automatically cleared to 0
immediately after they are read. Double latching is implemented on these bits so that set bits remain stable
throughout the read cycle. All bits that were set are cleared when read and new interrupts that are pending during
the read cycle are held until after the cycle is completed. One, two, or three bits can be set when reading Register
C. Each used flag bit should be examined when read to ensure that no interrupts are lost.
The flag bits in Extended Register 4A are not automatically cleared following a read. Instead, each flag bit can be
cleared to 0 only by writing 0 to that bit.
When using the flag bits with fully enabled interrupts, the IRQ line is driven low when an interrupt flag bit is set and
its corresponding enable bit is also set. IRQ is held low as long as at least one of the six possible interrupt sources
has its flag and enable bits both set. The IRQF bit in Register C is a 1 whenever the IRQ pin is being driven low as
a result of one of the six possible active sources. Therefore, determination that the DS1685/DS1687 initiated an
interrupt is accomplished by reading Register C and finding IRQF = 1. IRQF remains set until all enabled interrupt
flag bits are cleared to 0.
相关PDF资料
PDF描述
DS1685E-5 1 TIMER(S), REAL TIME CLOCK, PDSO24
DS1685QN-3 1 TIMER(S), REAL TIME CLOCK, PQCC28
DS1685QN-5 1 TIMER(S), REAL TIME CLOCK, PQCC28
DS1685SN-5 1 TIMER(S), REAL TIME CLOCK, PDSO24
DS1687-3 1 TIMER(S), REAL TIME CLOCK, DIP24
相关代理商/技术参数
参数描述
DS1685S-3/T&R 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
DS1685S-3/TR 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:3V/5V Real-Time Clocks
DS1685S-3_12 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:3V/5V Real-Time Clocks
DS1685S-3+ 功能描述:实时时钟 3V/5V RTC 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
DS1685S-3+T& 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:3V/5V Real-Time Clocks