參數(shù)資料
型號: DS1603
元件分類: 通用總線功能
英文描述: Elapsed Time Counter Module
中文描述: 歷時計數(shù)器模塊
文件頁數(shù): 2/8頁
文件大?。?/td> 104K
代理商: DS1603
DS1603
2 of 8
clock input. After the first eight clock cycles have loaded the protocol register with a valid protocol
additional clocks will output data for a read or input data for a write. V
CC
must be present to access the
DS1603. If V
CC
< the internal power supply (approximately 3.0 volts) the DS1603 will switch to internal
power and disable the serial port to conserve energy. When running off of the internal power supply, only
the continuous counter will continue to count and the counter powered by V
CC
will stop, but retain the
count which had accumulated when V
CC
power was lost.
PROTOCOL REGISTER
The protocol bit definition is shown in Figure 2. Valid protocols and the resulting actions are shown in
Table 1. Each data transfer to the protocol register designates what action is to occur. As defined, the
MSB (bit 7 which is designated ACC) selects the 32–bit continuous counter for access. If ACC is a
logical 1 the continuous counter is selected and the 32 clock cycles that follow the protocol will either
read or write this counter. If the counter is being read, the contents will be latched into a different register
at the end of protocol and the latched contents will be read out on the next 32 clock cycles. This avoids
reading garbled data if the counter is clocked by the oscillator during a read. Similarly, if the counter is to
be written, the data is buffered in a register and all 32 bits are jammed into the counter simultaneously on
the rising edge of the 32
nd
clock. The next bit (bit 6 which is designated AVC) selects the 32–bit V
CC
active counter for access. If AVC is a logical 1 this counter is selected and the 32 clock cycles that follow
will either read or write this counter. If both bit 7 and bit 6 are written to a logic high, all clock cycles
beyond the protocol are ignored and bit 5, 4, and 3 are loaded into the oscillator trim register. A value of
binary 3 (011) will give a clock accuracy of
±
120 seconds per month at 25
°
C. Increasing the binary
number towards 7 will cause the real time clock to run faster. Conversely, lowering the binary number
towards 0 will cause the clock to run slower. Binary 000 will stop the oscillator completely. This feature
can be used to conserve battery life during storage. In this mode the internal power supply current is
reduced to 100 nA maximum. In applications where oscillator trimming is not practical or not needed, a
default setting of 011 is recommended. Bit 2 of protocol (designated CCC) is used to clear the continuous
counter. When set to logic 1, the continuous counter will reset to 0 when
RST
is taken low. Bit 1 of
protocol (designated CVC) is used to clear the V
CC
active counter. When set to logical 1, the V
CC
active
counter will reset to 0 when
RST
is taken low. Both counters can be reset simultaneously by setting CCC
and CVC both to a logical 1. Bit 0 of the protocol (designated RD) determines whether the 32 clocks to
follow will write a counter or read a counter. When RD is set to a logical 0 a write action will follow
when RD is set to a logical 1 a read action will follow. When sending the protocol, 8 bits should always
be sent. Sending less than 8 bits can produce erroneous results. If clearing the counters or trimming the
oscillator, the data transfer can be terminated after the 8–bit protocol is sent. However, when reading or
writing the counters, 32 clock cycles should always follow the protocol.
RESET AND CLOCK CONTROL
All data transfers are initiated by driving the
RST
input high. The
RST
input has two functions. First,
RST
turns on the serial port logic which allows access to the protocol register for the protocol data entry.
Second, the
RST
signal provides a method of terminating the protocol transfer or the 32–bit counter
transfer. A clock cycle is a sequence of a falling edge followed by a rising edge. For write inputs, data
must be valid during the rising edge of the clock. Data bits are output on the falling edge of the clock
when data is being read. All data transfers terminate if the
RST
input is transitioned low and the DQ pin
goes to a high impedance state.
RST
should only be transitioned low while the clock is high to avoid
disturbing the last bit of data. All data transfers must consist of 8 bits when transferring protocol only or 8
+ 32 bits when reading or writing either counter. Data transfer is illustrated in Figure 3.
相關PDF資料
PDF描述
DS1609 Dual Port RAM
DS1615 Temperature Recorder
DS1615S Temperature Recorder
DS1615X Temperature Recorder
DS1616 Temperature and Three Input MUX’ed 8-bit Data Recorder
相關代理商/技術參數(shù)
參數(shù)描述
DS1603+ 功能描述:實時時鐘 RoHS:否 制造商:Microchip Technology 功能:Clock, Calendar. Alarm RTC 總線接口:I2C 日期格式:DW:DM:M:Y 時間格式:HH:MM:SS RTC 存儲容量:64 B 電源電壓-最大:5.5 V 電源電壓-最小:1.8 V 最大工作溫度:+ 85 C 最小工作溫度: 安裝風格:Through Hole 封裝 / 箱體:PDIP-8 封裝:Tube
DS1603J 制造商:NSC 制造商全稱:National Semiconductor 功能描述:TRI-STATE Dual Receiver
DS1603J/883 制造商:National Semiconductor Corporation 功能描述:Dual Receiver 14-Pin CDIP
DS1603N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog Timer Circuit
DS16-03P 制造商:Cooper Bussmann 功能描述:TOP SCREW-ON INSERTION BRIDGE, 3 POLE, F - Bulk 制造商:COOPER BUSSMANN 功能描述:TOP SCREW-ON INSERTION BRIDGE, 3 POLE, F