8-bit General Purpose GB MCUs

  • Not Recommended for New Designs
  • This page contains information on a product that is not recommended for new designs.

Product Details

Block Diagram

Freescale S08GB Microcontroller Block Diagram

Freescale S08GB Microcontroller Block Diagram


8-bit HCS08 CPU Core

  • Low-power technology
    • Multiple power management modes, including 20 nA powerdown
    • Optional autowake-up from Stop 2 or Stop 3 modes with internal timer typically requires only 300 nA additional current
    • 1.8V operation
  • High performance when needed
    • 50 ns minimum instruction cycle time down to 2.1V at 20 MHz bus
    • 125 ns minimum instruction cycle time down to 1.8V at 8 MHz bus
  • C-optimized architecture with multiply and divide instructions

On-Chip Debug Interface

  • Single-wire background debug mode
  • On-chip trace buffer with nine flexible trigger modes and multiple hardware breakpoints
  • Nonintrusive emulation

Integrated Third-Generation Flash Memory

  • In-application reprogrammable
  • Self-timed, fast programming
    • Can program 8 bits in 20 µs
    • Fast Flash page erase
      • 20 ms (512B)
  • 10K write/erase cycles minimum, 100K typical
  • 15-year minimum data retention, 100 years typical
  • Internal program/erase voltage generation
  • Fine Flash granularity—512B Flash erase/1B Flash program
  • Flexible block protection and enhanced security

Internal Clock Generator

  • Programmable frequency-locked loop (FLL) generates 8 MHz to 40 MHz (for bus rates up to 20 MHz)
  • Post-FLL divider gives one of eight bus rate dividers
  • Trimmable with temperature and voltage compensation (<2 percent drift)
  • Provides multiple options for clock sources and in-application clock switching
    • 32 kHz to 16 MHz external crystal/resonator
    • Internal clock generator
    • External clock

10-bit Analog-to-Digital Converter (ADC)

  • Eight-channel ADC
  • 14 µs, 10-bit single conversion time

Timer with Eight Programmable Channels

  • Three-channel and five-channel, 16-bit timer systems
  • Each channel programmable for
    • Input capture, output compare or buffered pulse-width modulator (PWM)
    • PWM can be edge-or center-aligned
  • 16-bit free-running or up/down (CPWM) count operation

Extensive Serial Communications

  • Dual asynchronous SCIs
    • Flexible 13-bit module-based baud rate generators
    • Double-buffered receive and transmit
  • Synchronous SPI
    • Up to 5 Mbps
  • Inter-IC (I2C) bus
    • Multicontroller operation
    • 256 clock options

System Protection

  • Selectable low-voltage detect/reset at nominal 1.8V
  • Low-battery warning at nominal 2.4V or 2.1V
  • COP watchdog timer

56 Input/Output (I/O) Lines

  • Programmable pull-ups
  • High-current drivers
  • Eight keyboard interrupts
  • Controlled rise/fall times minimize noise


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Design Resources

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Note: For better experience, software downloads are recommended on desktop.


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