DESCRIPTION

The DS87C530/DS83C530 EPROM/ROM Micro with Real Time Clock is an 8051-compatible microcontroller based on the Dallas high-speed core. It uses 4 clocks per instruction cycle instead of 12 used by the standard 8051. It also provides a unique mix of peripherals not widely available on other processors. They include an on-chip Real Time Clock (RTC) and battery back up support for an on-chip 1k x 8 SRAM. The new Power Management Mode allows software to select reduced power operation while still processing.

FEATURES

■ 80C52-compatible

- 8051 instruction set-compatible

- Four 8-bit I/O ports

- Three 16-bit timer/counters

- 256 bytes scratchpad RAM

■ Large on-chip memory

- 16 kB EPROM (OTP)

- 1 kB extra on-chip SRAM for MOVX

■ ROMSIZE Feature

- Selects effective on-chip ROM size from 0 to 16kB

- Allows access to entire external memory map

- Dynamically adjustable by software

- Useful as boot block for external Flash

■ Nonvolatile Functions

- On-chip Real Time Clock w/ Alarm Interrupt

- Battery backup support of 1 kB SRAM

■ High-Speed Architecture

- 4 clocks/machine cycle (8051 = 12)

- Runs DC to 33 MHz clock rates

- Single-cycle instruction in 121 ns

- Dual data pointer

- Optional variable length MOVX to access fast/slow RAM /peripherals

■ Power Management Mode

- Programmable clock source saves power

- Runs from (crystal/64) or (crystal/1024)

- Provides automatic hardware and software exit

■ EMI Reduction Mode disables ALE

■ Two full-duplex hardware serial ports

■ High integration controller includes:

- Power-Fail Reset

- Early-Warning Power-Fail Interrupt

- Programmable Watchdog Timer

■ 14 total interrupt sources with 6 external