MC68HC68T1P Freescale Semiconductor, Inc, MC68HC68T1P Datasheet
MC68HC68T1P
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MC68HC68T1P Summary of contents
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... MC68302”, and AN1065 “Use of the MC68HC68T1 Real–Time Clock with Multiple Time Bases” MICROWIRE is a trademark of National Semiconductor Inc. REV 2 2/96 MOTOROLA Motorola, Inc. 1996 MC68HC68T1 ORDERING INFORMATION MC68HC68T1P MC68HC68T1DW SOG Package PIN ASSIGNMENT CLKOUT 1 CPUR 2 INT 3 SCK 4 MOSI 5 ...
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XTAL in OSCILLATOR PRESCALE 15 XTAL out 13 V BATT 11 50/60 Hz LINE STOP/START PRESCALE SELECT 1 CLKOUT CONTROL REG CLOCK 3 AND INT INT LOGIC CONTROL REG 12 POWER V SYS SENSE 10 POR CONTROL 9 PSE ...
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ABSOLUTE MAXIMUM RATINGS* (Voltages Referenced Symbol Parameter Supply Voltage Input Voltage (except Line Input**) V out DC Output Voltage Input Current, per Pin I out DC Output ...
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AC ELECTRICAL CHARACTERISTICS Symbol f SCK Maximum Clock Frequency (Refer to SCK below) t PLH , Maximum Propagation Delay, SCK to MISO t PHL t PLZ , Maximum Propagation Delay MISO t PHZ t PZL ...
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w(L) SCK t w(H) 1/f SCK MOSI W NOTE: Measurement points are V IL and V IH unless otherwise noted on the AC Electrical Characteristics table w(L) SCK ...
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OPERATING CHARACTERISTICS The real–time clock consists of a clock/calendar and RAM (see Figure 5). Communication with the device may be established via a serial peripheral interface (SPI) or MICROWIRE bus. In addition to the clock/calendar data ...
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FREEZE FUNCTION The freeze function prevents an increment of the time counters, if any of the registers are being read. Also, alarm operation is delayed if the registers are being read. This causes the clock to lose time with increasing ...
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BYTES GENERAL–PURPOSE USER RAM READ ADDRESSES ONLY CLOCK/CALENDAR READ ADDRESSES ONLY NOT USED 32 BYTES GENERAL–PURPOSE USER RAM WRITE ADDRESSES ONLY CLOCK/CALENDAR WRITE ADDRESSES ONLY MC68HC68T1 8 HEXADECIMAL $ DAY OF THE WEEK R DATE OF THE ...
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HEX ADDRESS READ WRITE DB7 $20 $A0 $21 $ $22 $ $23 $A3 $24 $A4 $25 $A5 $26 $A6 $31 $B1 7 $32 $B2 7 N/A $A8 N/A $A9 X N/A $AA $B0 N/A 7 $00 ...
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Table 1. Clock/Calendar and Alarm Data Modes Address Location Read Write $20 $A0 Seconds $21 $A1 Minutes $22 $A2 Hours** (12 Hour Mode) Hours (24 Hour Mode) $23 $A3 Day of Week (Sunday = 1) $24 $A4 Date of Month ...
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NOTE Hz p–p sine–wave voltage is an acceptable signal to present at the LINE input pin. Figure 8. Power Sensing Functional Diagram MSB 1 INTERRUPT CONTROL REGISTER SERIAL INTERFACE REAL–TIME CLOCK MC68HC68T1 ...
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INT NOTE: The V SYS pin must be powered up. Figure 10. Power–Up Functional Diagram (Initiated by Internal Interrupt Signal Generation) V BATT Figure 11. Power–Up Functional Diagram (Initiated by a Rise in Voltage on the V SYS Pin) MC68HC68T1 ...
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PIN DESCRIPTIONS CLKOUT Clock Output (Pin 1) This signal is the buffered clock output which can provide one of the seven selectable frequencies (or this output can be reset low). The contents of the three least significant bit positions in ...
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LINE Line Sense (Pin 11) The LINE sense input can be used to drive one of two functions. The first function utilizes the input signal as the fre- quency source for the timekeeping counters. This function is selected by setting ...
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Resistor R1 is recommended operation. Consult crystal manufacturer for R1 value for oth- er frequencies. Resistor R2 must be used in 32 kHz opera- W tion only. Use a 200 to 300 k range. This stabilizes ...
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After the status register is read, the first time–up bit is set low if the POR pin is high. Conversely, if the POR pin is held low, the first time–up bit remains set high. Interrupt True A high in this ...
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SS CPOL = 1* SCK SS CPOL = 0* SCK MOSI * CPOL is a bit that is set in the microcomputer’s Control Register. Figure 13. Serial Clock (SCK Function of MCU Clock Polarity (CPOL) SS Î Î ...
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Address Byte The address byte is always the first byte entered after SS goes true. To transmit a new address, SS must first be brought low and then taken high again. MSB — ...
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BRIDGE/ LOW VOLTAGE REGULATOR AC LINE NOTE 1 NOTES: 1. Clock circuit driven by line input frequency. 2. Power–on reset circuit included to detect power failure MC68HC11 MCU is used, delete the capacitor at the RESET pin. ...
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BRIDGE/ AC LINE REGULATOR NOTE 2 NOTE 1 NOTES: 1. The LINE input pin can sense when the switch opens by use of the power sense interrupt. The MC68HC68T1 crystal drives the clock input to the CPU using the CLKOUT ...
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BRIDGE/ AC LINE REGULATOR R CHARGE NOTE 1 NOTES: 1. See Figure 12 for 32.768 kHz operation. This configuration, where the MC68HC68T1 supplies the MCU clock, usually requires MHz crystal MC68HC11 MCU is ...
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CLOCK BUTTON IGNITION 5 V REG 11 + LINE – 100 BATT m 10 0.1 F POR MC68HC68T1 NOTE 1 14 XTAL 2 MHz 15 NOTES: 1. The V SYS and Line inputs can ...
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V NON–RECHARGEABLE BATTERY – 0 0 Actual values may vary, depending on recommendations of crystal manufacturer. Figure 22. Non–Rechargeable Battery–Backup System MOTOROLA LIMIT D BLOCK W 100 ...
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TROUBLESHOOTING 1. The circuit works, but the standby current is well above the spec. How can the standby current be reduced using a 32.768 kHz crystal, include a series resistor in the circuit per Figure 12 of the ...
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0.25 (0.010 SOG (SMALL OUTLINE GULL–WING) PACKAGE - - - 0.25 (0.010 ...
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Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of ...