DS87C550

DESCRIPTION

The DS87C550 EPROM High-Speed Micro with A/D and PWM is a member of the fastest 100% 8051-compatible microcontroller family available. It features a redesigned processor core that removes wasted clock and memory cycles. As a result, it executes 8051 instructions up to three times faster than the original architecture for the same crystal speed. The DS87C550 also offers a maximum crystal speed of 33 MHz, resulting in apparent execution speeds of up to 99 MHz.

FEATURES

■ 87C52-Compatible
- 8051 pin- and instruction set-compatible
- Three 16-bit timer/counters
- 256 bytes scratchpad RAM
■ On-chip Memory
- 8 kbytes EPROM (OTP & Windowed Packages)
- 1 kbyte extra on-chip SRAM for MOVX access
■ On-chip Analog to Digital Converter
- Eight channels of analog input, 10-bit resolution
- Fast conversion time
- Selectable internal or external reference voltage
■ Pulse Width Modulator Outputs
- Four channels of 8-bit PWM
- Channels cascadable to 16-bit PWM
■ 4 Capture + 3 Compare Registers
■ 55 I/O Port Pins
■ New Dual Data Pointer Operation
- Either data pointer can be incremented or
decremented
■ ROMSIZE Feature
- Selects effective on-chip ROM size from 0 to 8k
- Allows access to entire external memory map
- Dynamically adjustable by software
■ High-Speed Architecture
- 4 clocks/machine cycle (8051 = 12)
- Runs DC to 33 MHz clock rates
- Single-cycle instruction in 121 ns
- New Stretch Cycle feature allows access to
fast/slow memory or peripherals
■ Unique Power Savings Modes
■ EMI Reduction Mode disables ALE when not
needed
■ High integration controller includes:
- Power-fail reset
- Early-warning power-fail interrupt
- Two full-duplex hardware serial ports
- Programmable watchdog timer
■ 16 total interrupt sources with 6 external