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Other Microcontrollers / Microprocessors. Overview. 68HC11 Application Example: An Emergency Communicator System (ECS) Other Microcontrollers / Microprocessors Selecting a Microcontroller / Microprocessor. 68HC11 Application Example. Emergency Communicator System (ECS) Function
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Overview 68HC11 Application Example: An Emergency Communicator System (ECS) Other Microcontrollers / Microprocessors Selecting a Microcontroller / Microprocessor
68HC11 Application Example • Emergency Communicator System (ECS) • Function • Records a set of personalized emergency messages • Dials customized telephone number(s) when triggered by a pushbutton, monitor, sensor, etc. • Monitors call status and delivers recorded message • Features • Uses standard telephone line; no need for special monitoring service • Reliable Based on: “Emergency Communicator System” David B. Wax, University of Pennsylvania May 1, 1991 1991 University Motorola Design Contest
ECS: Use of the 68HC11 (1) • HCMOS • Low power - operates on battery backup • Noise immunity - operates in environment with telephone line and (possibly) radio transmitters • EEPROM • Calibration table - reference values for dial tones, busy signals, ring back signals, etc. • User parameters - telephone numbers to call for various emergencies • System configuration - locations of emergency message “phrases” in memory • Analog-to-digital converter • Convert voice input to digital for recording message phrases
ECS: Use of the 68HC11 (2) • Serial peripheral interface • Transmits serial ASCII data to an LCD display unit for user interface • Timer subsystem • Input capture functions measures signals on telephone line to monitor call status • Real-time interrupt displays time since call request • Parallel input/output • Control input and outputs (simple mode) • External memory interface • STOP and WAIT modes • Reduce power consumption when unit is idle
ECS: Use of the 68HC11 (3) • Clock monitor • While in WAIT mode, the clock monitor verifies correct operation and can reset the system if an error is detected • Highest priority interrupt • IRQ is elevated to highest priority since it indicates a request for an emergency message
ECS: Context Diagram • What is the environment of the system that we are to design? ...
ECS: Top-Level Control/Data Flow • Identify the interface and “core” functions ...
ECS: System Control Data/Control Flow Decomposition • Decompose functions to a manageable design entity ...
ECS: Analysis Results • Analysis leads to: • System decomposition • Control and data transformations • Data elements • Information flows • Critical events • Requirements for the transformations and data elements derived from • System requirements • Operational scenarios • Supporting requirements
ECS: Analysis Results • Allocation of transformations and data elements to design entities that can be assigned to an individual designer or design team • Requirements for each entity based on those for the individual transformations and data elements • Functional analysis leading to physical realization
Other Microcontrollers • Motorola • 68HC05 - low-cost 8-bit “core” • 68HC11 - high-performance 8-bit core • 68HC16 - 16-bit core • 68300 family - high-performance 32-bit core • Intel • MCS-51 family - moderate-performance 8-bit core • MCS-96 - 16-bit core • 8096 - low-cost 16-bit core • 80196 - high-performance 16-bit core • Embedded processor versions of 80386 and i960 RISC processor
Other Microcontrollers • There are other vendors • Fujitsu • AMD • Philips • TI • Others ...
Motorola 68HC05 (2) • Block diagram
Motorola 68300 Family (1) • Features (68332) • 32-bit microcontroller • Based on CPU32 architecture (same as 680X0 family) with new instructions for controller applications • Low power operation (600 mW maximum, 500 µW in standby mode) • 132-pin plastic quad flat pack (PQFP) package • 16-bit intelligent timer • 16 independent channels and pins • Any channel can perform input capture, output compare, pulse width modulation
Motorola 68300 Family (2) • Serial ports • 68HC11-type SCI • 68HC11-type SPI with I/O queue • On-chip 2K bytes standby RAM • On-chip programmable chip select logic with up to 12 output signals • Up to 32 discrete I/O pins • System failure protection
Motorola 68300 Family (3) • Block diagram
Motorola 68300 Family (4) • Register diagram
Intel MCS-51 Family (1) • Features • 8-bit CPU • 0, 4K, 8K, 16K bytes on-chip ROM or EPROM • 128 or 256 bytes on-chip RAM • 64K address space for external data memory, 64K address space for external program memory • 32 input/output pins • Full-duplex serial I/O • Two (or three) 16-bit timer/counters • Five (or six) interrupt sources with two priority level (preemptive) • Boolean processor • Other vendors make MCS-51 compatible devices • Philips • Built-in Inter-Integrated Circuit (I2C) Bus controller
Intel MCS-51 Family (2) • Block diagram
Intel MCS-96 Family (1) • Features • 16-bit CPU • Reconfigurable 8- or 16-bit external bus • 8K bytes on-chip ROM or EPROM • 232 bytes on-chip RAM • Hardware multiply and divide • High-speed I/O unit (6 dedicated lines, 2 programmable lines) • 10-bit analog-to-digital converter • Full duplex serial port • Up to 40 I/O ports • 21 interrupt sources with 8 programmable vectors • Pulse width modulated (PWM) output (for PWM output or conversion to analog) • Watchdog timer • 48-pin DIP and 68-pin PLCC packages
Intel MCS-96 Family (2) • Block diagram
Processor Selection Factors • Economics • Parts cost • Parts quality • Development cost • Software development • Development tools • Test • Expertise and learning curve • Political • Pacts, cooperative agreements • Investment interest • Technical • Application features matched to processor features • Development tools
Application Characteristics (1) • Data processing • Analysis of application should focus on critical calculations that must be completed within real-time constraints • Precision of calculations: 8-, 16-, 32-bits? • Type of data: floating point, signed, unsigned? • Input/output • Number of signals • Special functions, e.g. serial I/O or handshaking • Power • Need for low-power consumption • Memory • Size: how much data, program memory? • Type: volatility, updates (patches), configuration?
Application Characteristics (2) • Real-time processing • Interrupt latency • Timing subsystem performance • Special functions • Analog-to-digital converters • Special drivers • Programmatic issues • Quantities • Development schedule
Development Tools • System-level (hardware and software) • Monitor programs • Logic analyzers • Emulators • Software-only • Software generation • Assemblers - 68HC11 assembly language • Compilers - C, PL/M • Interpreters - FORTH, BASIC • Simulators
When Not to Use a Microprocessor/Microcontroller • Purely analog system • Examples: amplifier, radio receiver, ... • Microcontroller or microprocessor may still be used for control • High volume products • Examples: calculators, mass market toys, low-cost feature telephones, Use custom or semicustom ICs • Low-end microcontrollers may be competitive • Very high performance applications • Examples: radar, real-time high-resolution image processing • Use custom logic or bipolar bit-sliced processor • High-end RISC microprocssors/microcontrollers and programmable digital signal processors (DSP) ICs may be competitive