Description
The MC68HC908GR8 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.
- 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)
- 7680 bytes of on-chip FLASH memory on the MC68HC908GR8 and 4096 bytes of on-chip FLASH memory
- 384 bytes of on-chip random-access memory (RAM)
- Serial peripheral interface module (SPI)
- Serial communications interface module (SCI)
- One 16-bit, 2-channel timer (TIM1) and one 16-bit, 1-channel timer (TIM2) interface modules with selectable input capture, output compare, and PWM capability on each channel
- 6-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 21 general-purpose input/output (I/O) pins, including:
- 19 shared-function I/O pins
- Up to two 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–PTC1
- 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
- 4-bit keyboard wakeup port
- 42-pin shrink dual in-line package (SDIP), 32-pin quad flat pack (QFP), 28-pin plastic dual-in-line package (DIP), or 28-pin small outline integrated circuit (SOIC)
- Specific features of the MC68HC908GR8 in 28-pin DIP and 28-pin SOIC are:
- Port B is only 4 bits: PTB0–PTB3; 4-channel ADC module
- No Port C bits
