General Description
●Introduction
●The MC68HC908QY4 is a member of the low-cost, high-performance M68HC08 Family of 8-bit microcontroller units (MCUs). The M68HC08 Family isa Complex Instruction Set Computer (CISC) with a Von Neumann architecture. All MCUs in the familyuse the enhanced M68HC08 central processor unit (CPU08) and are available with a variety of modules, memory sizes and types, and package types.
●Features
●Features include:
●• High-performance M68HC08 CPU core
●• Fully upward-compatible object code with M68HC05 Family
●• 5-V and 3-V operating voltages (VDD)
●• 8-MHz internal bus operation at 5 V, 4-MHz at 3 V
●• Trimmable internal oscillator
●– 3.2 MHz internal bus operation
●– 8-bit trim capability allows 0.4% accuracy(1)
●– ± 25% untrimmed
●• Auto wakeup from STOP capability
●• Configuration (CONFIG) register for MCU configuration options, including:
●– Low-voltage inhibit (LVI) trip point
●• In-system FLASH programming
●• FLASH security(2)
●• On-chip in-application programmable FLASH memory (with internal program/erase voltage generation)
●– MC68HC908QY4 and MC68HC908QT4 — 4096 bytes
●– MC68HC908QY2, MC68HC908QY1, MC68HC908QT2, and MC68HC908QT1 — 1536 bytes
●• 128 bytes of on-chip random-access memory (RAM)
●• 2-channel, 16-bit timer interface module (TIM)
●• 4-channel, 8-bit analog-to-digital converter (ADC) on MC68HC908QY2, MC68HC908QY4, MC68HC908QT2, and MC68HC908QT4
●• 5 or 13 bidirectional input/output (I/O) lines and one input only:
●– Six shared with keyboard interrupt function and ADC
●– Two shared with timer channels
●– One shared with external interrupt (IRQ)
●– Eight extra I/O lines on 16-pin package only
●– High current sink/source capability on all port pins
●– Selectable pullups on all ports, selectable on an individual bit basis
●– Three-state ability on all port pins
●• 6-bit keyboard interrupt with wakeup feature (KBI)
●• Low-voltage inhibit (LVI) module features:
●– Software selectable trip point in CONFIG register
●• System protection features:
●– Computer operating properly (COP) watchdog
●– Low-voltage detection with reset
●– Illegal opcode detection with reset
●– Illegal address detection with reset
●• External asynchronous interrupt pin with internal pullup (IRQ) shared with general-purpose input pin
●• Master asynchronous reset pin (RST) shared with general-purpose input/output (I/O) pin
●• Power-on reset
●• Internal pullups on IRQand RSTto reduce external components
●• Memory mapped I/O registers
●• Power saving stop and wait modes
●• MC68HC908QY4, MC68HC908QY2, and MC68HC908QY1 are available in these packages:
●– 16-pin plastic dual in-line package (PDIP)
●– 16-pin small outline integrated circuit (SOIC) package
●– 16-pin thin shrink small outline package (TSSOP)
●• MC68HC908QT4, MC68HC908QT2, and MC68HC908QT1 are available in these packages:
●– 8-pin PDIP
●– 8-pin SOIC
●– 8-pin dual flat no lead (DFN) package
●Features of the CPU08 include the following:
●• 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
