Microcontrollers Overview

Microcontroller Overview

• A microcontroller is a single chip that integrates a microprocessor system, requiring only power and clocking.
• The term "micro" comes from the Greek word "Micros", meaning small in size, quantity, number, and dignity.

Components of a Microcontroller

• A microcontroller combines the CPU core, memory (ROM and RAM), and parallel digital I/O on a single chip.
• Other components often included are:
  • Timer module
  • Serial I/O
  • Analog-to-Digital Converter (ADC)
  • Analog Comparator

CPU Core

• The CPU core is the heart of the microcontroller.
• Traditionally based on an 8-bit microprocessor unit.
• Registers serve as memory locations, enabling mathematical operations and data processing.

Memory

• Memory is responsible for storing data.
• Types of memory:
  • Volatile RAM (Random Access Memory)
  • Non-Volatile ROM (Read Only Memory)
  • EPROM (Erasable Programmable Read Only Memory)
  • EEPROM (Electrically Erasable Programmable Read Only Memory)
  • Flash EEPROM

Bus

• A bus represents a group of wires (8, 16, or more) that connect blocks inside the microcontroller.
• Two types of buses:
  • Address bus: transmits addresses from CPU to memory.
  • Data bus: transmits data, as wide as the data (8 bits, etc.).

Timer Unit

• A timer unit is a counter driven by an external clock pulse or the microcontroller's internal oscillator.
• Watchdog timer: a timer that is refreshed by the user program, resetting if not refreshed.

Serial Communication

• Serial communication (RS232) enables microcontrollers to connect to other microcontrollers or PCs using a serial cable.

Analog-to-Digital Converter (ADC)

• An ADC converts analog signals (e.g., voltage) to digital form for microcontroller processing.

Analog Comparator

• Analog comparators are used to compare two analog voltages.