OKI M6242B

… Real Time Clock (RTC) – Amiga-Uhrenbaustein

OKI M6242B für: - z.B. A500, A500+, A2000
und auch diverse Speicher- bzw. Prozessor-Karten

The MSM6242B is a silicon gate CMOS Real Time Clock/Calendar for use in direct busconnection Microprocessor/Microcomputer applications. An on-chip 32.768 KHz crystal oscillator time base is divided to provide addressable 4-bit I/O data for SECONDS, MINUTES, HOURS, DAY OF WEEK, DATE, MONTH and YEAR. Data access is controlled by 4-bit address, chip selects (CSO, CS1), WRITE, READ, and ALE. Control Registers D, E and F provide for 30 SECOND error adjustment, INTERRUPT REQUEST (IRQ FLAG) and BUSY status bits, clock STOP, HOLD, and RESET FLAG bits, 4 selectable INTERRUPTS rates are available at the STD.P ¡ Semiconductor MSM6242B DIRECT BUS CONNECTED CMOS REAL TIME CLOCK/CALENDAR (STANDARD PULSE) output utilizing Control Register inputs T0, T1 and the ITRPT/ STND (INTERRUPT/STANDARD). Masking of the interrupt output (STD.P) can be accomplished via the MASK bit. The MSM6242B can operate in a 12/24 hour format and Leap Year timing is automatic. The MSM6242B normally operates from a 5V ±10% supply at –40 to 85°C. Battery backup operation down to 2.0V allows continuation of time keeping when main power is off. The MSM6242B is offered in a 18-pin plastic DIP and a 24-pin plastic Small Outline package.

FEATURES: DIRECT MICROPROCESSOR/MICROCONTROLLER BUS CONNECTION

• 4-bit data bus
• 4-bit address bus
• READ, WRITE, ALE and CHIP SELECT INPUTS
• Status registers – IRQ and BUSY
• Selectable interrupt outputs – 1/64
  second, 1 second, 1 minute, 1 hour
• Interrupt masking
• 32.768 KHz crystal controlled operation
• 12/24 hour format
• Auto leap year
• ±30 second error correction
• Single 5V supply
• Battery backup down to VDD = 2.0V
• Low power dissipation:
  20μW max at VDD = 2V
  150μW max at VDD = 5V
• 18 pin Plastic DIP (DIP18-P-300)
• 24 Pin-V Plastic SOP (SOP24-P-430-VK)

• Quelle
  • Datenblatt, Commodore-Unterlagen
• Datenblatt
  • M6242B (149kB)
• siehe auch:
  • Echtzeituhr
  • Ricoh RP5C01