General Description

Introduction

The MC68HC908GP32 is a member of the low-cost, high-performance M68HC08 Family of 8-bit microcontroller units (MCUs). All MCUs in the family use the enhanced M68HC08 central processor unit (CPU08) and are available with a variety of modules, memory sizes and types, and package types.

Features

For convenience, features have been organized to reflect:

• Standard features of the MC68HC908GP32

• Features of the CPU08

Standard Features of the MC68HC908GP32

• High-performance M68HC08 architecture optimized for C-compilers

• Fully upward-compatible object code with M6805, M146805, and M68HC05 Families

• 8-MHz internal bus frequency

• FLASH program memory security(1)

• On-chip programming firmware for use with host personal computer which does not require high voltage for entry

• In-system programming

• System protection features:

– Optional computer operating properly (COP) reset

– Low-voltage detection with optional reset and selectable trip points for 3.0-V and 5.0-V operation

– Illegal opcode detection with reset

– Illegal address detection with reset

• Low-power design; fully static with stop and wait modes

• Standard low-power modes of operation:

– Wait mode

– Stop mode

• Master reset pin and power-on reset (POR)

• 32 Kbytes of on-chip FLASH memory with in-circuit programming capabilities of FLASH program memory

• 512 bytes of on-chip random-access memory (RAM)

• Serial peripheral interface module (SPI)

• Serial communications interface module (SCI)

• Two 16-bit, 2-channel timer interface modules (TIM1 and TIM2) with selectable input capture, output compare, and PWM capability on each channel

• 8-channel, 8-bit successive approximation analog-to-digital converter (ADC)

• BREAK module (BRK) to allow single breakpoint setting during in-circuit debugging

• Internal pullups on IRQ and RST to reduce customer system cost

• Clock generator module with on-chip 32-kHz crystal compatible PLL (phase-lock loop)

• Up to 33 general-purpose input/output (I/O) pins, including:

– 26 shared-function I/O pins

– Five or seven dedicated I/O pins, depending on package choice

• Selectable pullups on inputs only on ports A, C, and D. Selection is on an individual port bit basis. During output mode, pullups are disengaged.

• High current 10-mA sink/10-mA source capability on all port pins

• Higher current 15-mA sink/source capability on PTC0–PTC4

• Timebase module with clock prescaler circuitry for eight user selectable periodic real-time interrupts with optional active clock source during stop mode for periodic wakeup from stop using an external 32-kHz crystal

• Oscillator stop mode enable bit (OSCSTOPENB) in the CONFIG register to allow user selection of having the oscillator enabled or disabled during stop mode

• 8-bit keyboard wakeup port

• 5-mA maximum current injection on all port pins to maintain input protection

• 40-pin plastic dual-in-line package (PDIP), 42-pin shrink dual-in-line package (SDIP), or 44-pin quad flat pack (QFP)

• Specific features of the MC68HC908GP32 in 40-pin PDIP are:

– Port C is only 5 bits: PTC0–PTC4

– Port D is only 6 bits: PTD0–PTD5; single 2-channel TIM module

• Specific features of the MC68HC908GP32 in 42-pin SDIP are:

– Port C is only 5 bits: PTC0–PTC4

– Port D is 8 bits: PTD0–PTD7; dual 2-channel TIM modules

• Specific features of the MC68HC908GP32 in 44-pin QFP are:

– Port C is 7 bits: PTC0–PTC6

– Port D is 8 bits: PTD0–PTD7; dual 2-channel TIM modules

Features of the CPU08

Features of the CPU08 include:

• Enhanced HC05 programming model

• Extensive loop control functions

• 16 addressing modes (eight more than the HC05)

• 16-bit index register and stack pointer

• Memory-to-memory data transfers

• Fast 8 × 8 multiply instruction

• Fast 16/8 divide instruction

• Binary-coded decimal (BCD) instructions

• Optimization for controller applications

• Efficient C language support