MM58274CV National Semiconductor, MM58274CV Datasheet
MM58274CV
Specifications of MM58274CV
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MM58274CV Summary of contents
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... Applications Point of sale terminals Y Teller terminals Y Word processors Y Data logging Y Industrial process control Y Block Diagram TRI-STATE is a registered trademark of National Semiconductor Corp Microbus trademark of National Semiconductor Corp C 1995 National Semiconductor Corporation TL F 11219 Features Same pin-out as MM58174A Y MM58274 Timekeeping from tenths of seconds to tens of years in ...
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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 STG Supply Voltage V DD Power Dissipation P D Lead Temperature (Soldering 10 seconds) ...
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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 Connection Diagrams Dual-In-Line Package Top View Order Number MM58274CJ MM58274CN or MM58274CV Read Cycle Timing (Notes 5 and 7) Write Cycle Timing (Notes 5 and 11219–4 FIGURE 2 See NS Package J16A N16A or V20A 11219 – 11219 – 3 PCC Package TL F 11219 – 5 ...
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Functional Description The MM58274C is a bus oriented microprocessor real time clock It has the same pin-out as the MM58174A while offer- ing extended timekeeping up to units and tens of years To enhance the device further a number of ...
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Functional Description (Continued) device which are synchronously clocked by this signal All time data and data-changed flag change on the falling edge of the clock setting pulse Data-Changed Flag The data-changed flag is set by the clock setting pulse to ...
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Functional Description (Continued) Day of Week Counter The day of week counter increments as the time rolls from ( 12-hour mode) It counts from and ...
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Functional Description (Continued) Control Register There are three registers which control different operations of the clock a) the clock setting register b) the interrupt register c) the control register The clock setting and interrupt registers both reside at ad- dress ...
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... METHODS OF DEVICE OPERATION Test Mode National Semiconductor uses test mode for functionally testing the MM58274C after fabrication and again after packaging Test mode can also be used to set up the oscil- lator frequency when the part is first commissioned ...
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Functional Description (Continued) Reading the Time Registers Using the data-changed flag technique supports microproc- essors with block move facilities as all the necessary time data may be read sequentially and then tested for validity as shown below 1) Read the ...
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Functional Description (Continued) FIGURE 5 MM58274C Microprocessor Interface Diagram FIGURE 6 Valid MM58274C Control Signals Using Chip Select Generated Access Strobes TL F 11219 – 11219 – 8 ...
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Functional Description (Continued) a Port Generated Read Access 2 Addresses Read Out b Port Generated Write Access 2 Addresses Written To FIGURE 7 Simple Port Generated Control Signals 11219 – 11219 – 11 ...
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Functional Description (Continued) APPLICATION HINTS Time Reading Using Interrupt In systems such as point of sale terminals and data loggers time reading is usually only required on a random demand basis Using the data-changed flag as outlined in the section ...
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Physical Dimensions inches (millimeters) Cavity Dual-In-Line Package (J) Order Number MM58274CJ NS Package Number J16A Molded Dual-In-Line Package (N) Order Number MM58274CN NS Package Number N16A 15 ...
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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 MM58274CV NS Package Number V20A 2 A critical component is any component of a life ...