The DS87C530/DS83C530 EPROM/ROM microcontrollers with a real-time clock (RTC) are 8051-compatible microcontrollers based on the Dallas Semiconductor high-speed core. They use 4 clocks per instruction cycle instead of the 12 used by the standard 8051. They also provide a unique mix of peripherals not widely available on other processors. They include an on-chip RTC and battery backup support for an on-chip 1k x 8 SRAM. The new Power Management Mode allows software to select reduced power operation while still processing. A combination of high-performance microcontroller core, RTC, battery-backed SRAM, and power management makes the DS87C530/DS83C530 ideal for instruments and portable applications. They also provide several peripherals found on other Dallas high-speed microcontrollers. These include two independent serial ports, two data pointers, on-chip power monitor with brownout detection and a watchdog timer. Power Management Mode (PMM) allows software to select a slower CPU clock. While default operation uses four clocks per machine cycle, the PMM runs the processor at 64 or 1024 clocks per cycle. There is a corresponding drop in power consumption when the processor slows. The EMI reduction feature allows software to select a reduced emission mode. This disables the ALE signal when it is unneeded. The DS83C530 is a factory mask ROM version of the DS87C530-ENL designed for high-volume, costsensitive applications. It is identical in all respects to the DS87C530, except that the 16kB of EPROM is replaced by a user-supplied application program. All references to features of the DS87C530-ENL will apply to the DS83C530, with the exception of EPROM-specific features where noted. Please contact your local Dallas Semiconductor sales representative for ordering information. Note: The DS87C530/DS83C530 are monolithic devices. A user must supply an external battery or super cap and a 32.768kHz timekeeping crystal to have permanently powered timekeeping or nonvolatile RAM. The DS87C530/DS83C530 provide all the support and switching circuitry needed to manage these resources. 
Feature
 
 
  
  - 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 
   
 
    - 16kB EPROM (OTP) 
 
    - 1kB Extra On-Chip SRAM for MOVX 
 
   
  
  - ROMSIZE Features 
   
 
    - 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 with Alarm Interrupt 
 
    - Battery Backup Support of 1kB SRAM 
 
   
  
  - High-Speed Architecture 
   
 
    - 4 Clocks/Machine Cycle (8051 = 12) 
 
    - Runs DC to 33MHz Clock Rates 
 
    - Single-Cycle Instruction in 121ns 
 
    - 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 Six External