ns32fx211 National Semiconductor Corporation, ns32fx211 Datasheet
ns32fx211
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ns32fx211 Summary of contents
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... NS32FX211 Microprocessor Compatible Real Time Clock General Description The NS32FX211 is fabricated using low threshold CMOS technology and is designed to operate in bus oriented mi- croprocessor systems where a real time clock and calendar function are required The on-chip 32 768 kHz crystal con- trolled oscillator will maintain timekeeping down ...
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Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications DC Input or Output Voltage Input or Output Diode Current Storage Temperature ...
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AC Switching Characteristics READ TIMING DATA FROM PERIPHERAL TO MICROPROCESSOR V Symbol Parameter t Address Bus Valid to Data Valid AD t Chip Select On to Data Valid CSD t Read Strobe On to Data Valid RD t Read Strobe ...
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... Switching Time Waveforms Functional Description The NS32FX211 is a bus oriented microprocessor real time clock Crystal Oscillator This consists of a CMOS inverter amplifier with an on-chip bias resistor Externally capacitor a 6 pF–40 pF trimmer capacitor and a crystal are suggested to complete the 32 768 kHz timekeeping oscillator circuit The 6 pF– ...
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Functional Description (Continued) FIGURE 3 Typical System Connection Diagram logic 1 The units and tens of seconds are set up by the processor giving time setting to the nearest second All three registers can be read by the processor for ...
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Functional Description (Continued) TABLE I Address Decoding of Real-Time Clock Internal Registers Registered Select AD3 0 Control Register 0 1 Tenths of Seconds 0 2 Units Seconds 0 3 Tens Seconds 0 4 Units Minutes 0 5 Tens Minutes 0 ...
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Functional Description (Continued) TABLE IIA Clock Setting Register Layout Function DB3 Leap Year Counter Indicator (12-Hour Mode) 12 24-Hour Select Bit Function Comments No Interrupt Interrupt Output Cleared Start Stop Bit Set Second ...
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... The read only portion of the control register has two status outputs Since the NS32FX211 keeps real time the time data chang- es asynchronously with the processor and this may occur while the processor is reading time data out of the clock ...
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... TV VCR clocks any system where real time is displayed The interrupt timer on the NS32FX211 can generate inter- rupts synchronously with the time registers changing using software to provide the initial synchronization In single interrupt mode the processor is responsible for ini- ...
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Functional Description (Continued) 2) Read out all the time registers required The registers may be read out in any order simplifying software require- ments 3) Read the lowest order register and compare it with the value stored previously in step ...
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... Physical Dimensions inches (millimeters) Cavity Dual-In-Line Package (J) Order Number NS32FX211J NS Package Number J16A Molded Dual-In-Line Package (N) Order Number NS32FX211N NS Package Number N16A 11 ...
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... National does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications Plastic Chip Carrier (V) Order Number NS32FX211V NS Package Number V20A 2 A critical component is any component of a life ...