Datasheet

ManualsBrandsNXP SEMICONDUCTORS ManualsMicrocontrollers, Microprocessors & QuartzesEmbedded microcontroller QFP 64 (14x14) 8-Bit 8 MHz I/O number 51

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Table Of Contents

List of Sections
Table of Contents
List of Figures
List of Tables
Section 1. General Description
- 1.1 Contents
- 1.2 Introduction
- 1.3 Features
- 1.4 MCU Block Diagram
- 1.5 Pin Assignments
- 1.6 Pin Functions
- 1.7 I/O Pin Summary
- 1.8 Signal Name Conventions
- 1.9 Clock Source Summary
Section 2. Memory Map
- 2.1 Contents
- 2.2 Introduction
- 2.3 Unimplemented Memory Locations
- 2.4 Reserved Memory Locations
- 2.5 Input/Output (I/O) Section
Section 3. Random-Access Memory (RAM)
- 3.1 Contents
- 3.2 Introduction
- 3.3 Functional Description
Section 4. FLASH Memory
- 4.1 Contents
- 4.2 Introduction
- 4.3 Functional Description
- 4.4 FLASH Control Register
- 4.5 FLASH Page Erase Operation
- 4.6 FLASH Mass Erase Operation
- 4.7 FLASH Program/Read Operation
- 4.8 FLASH Block Protection
  - 4.8.1 FLASH Block Protect Register
- 4.9 Wait Mode
- 4.10 Stop Mode
Section 5. EEPROM
- 5.1 Contents
- 5.2 Introduction
- 5.3 Features
- 5.4 Functional Description
- 5.5 EEPROM Configuration
- 5.6 EEPROM Timebase Requirements
- 5.7 EEPROM Security Options
- 5.8 EEPROM Block Protection
- 5.9 EEPROM Programming and Erasing
  - 5.9.1 EEPROM Programming
  - 5.9.2 EEPROM Erasing
- 5.10 Low Power Modes
  - 5.10.1 Wait Mode
  - 5.10.2 Stop Mode
- 5.11 EEPROM Registers
Section 6. Configuration Register (CONFIG)
- 6.1 Contents
- 6.2 Introduction
- 6.3 Functional description
- 6.4 Configuration Register 1
- 6.5 Configuration Register 2
Section 7. Central Processor Unit (CPU)
- 7.1 Contents
- 7.2 Introduction
- 7.3 Features
- 7.4 CPU Registers
- 7.5 Arithmetic/Logic Unit (ALU)
- 7.6 Low-Power Modes
  - 7.6.1 Wait Mode
  - 7.6.2 Stop Mode
- 7.7 CPU During Break Interrupts
- 7.8 Instruction Set Summary
- 7.9 Opcode Map
Section 8. System Integration Module (SIM)
- 8.1 Contents
- 8.2 Introduction
- 8.3 SIM Bus Clock Control and Generation
- 8.4 Reset and System Initialization
  - 8.4.1 External Pin Reset
  - 8.4.2 Active Resets from Internal Sources
- 8.5 SIM Counter
- 8.6 Exception Control
- 8.7 Low-Power Modes
  - 8.7.1 Wait Mode
  - 8.7.2 Stop Mode
- 8.8 SIM Registers
Section 9. Clock Generator Module (CGM)
- 9.1 Contents
- 9.2 Introduction
- 9.3 Features
- 9.4 Functional Description
- 9.5 I/O Signals
- 9.6 CGM Registers
- 9.7 Interrupts
- 9.8 Low-Power Modes
  - 9.8.1 Wait Mode
  - 9.8.2 Stop Mode
- 9.9 CGM During Break Interrupts
- 9.10 Acquisition/Lock Time Specifications
Section 10. Monitor ROM (MON)
- 10.1 Contents
- 10.2 Introduction
- 10.3 Features
- 10.4 Functional Description
- 10.5 Security
- 10.6 Extended Security
Section 11. Timer Interface Module A (TIMA)
- 11.1 Contents
- 11.2 Introduction
- 11.3 Features
- 11.4 Pin Name Conventions
- 11.5 Functional Description
- 11.6 Interrupts
- 11.7 Low-Power Modes
  - 11.7.1 Wait Mode
  - 11.7.2 Stop Mode
- 11.8 TIMA During Break Interrupts
- 11.9 I/O Signals
  - 11.9.1 TIMA Clock Pin
  - 11.9.2 TIMA Channel I/O Pins
- 11.10 I/O Registers
Section 12. Timer Interface Module B (TIMB)
- 12.1 Contents
- 12.2 Introduction
- 12.3 Features
- 12.4 Pin Name Conventions
- 12.5 Functional Description
- 12.6 Interrupts
- 12.7 Low-Power Modes
  - 12.7.1 Wait Mode
  - 12.7.2 Stop Mode
- 12.8 TIMB During Break Interrupts
- 12.9 I/O Signals
  - 12.9.1 TIMB Clock Pin
  - 12.9.2 TIMB Channel I/O Pins
- 12.10 I/O Registers
Section 13. Programmable Interrupt Timer (PIT)
- 13.1 Contents
- 13.2 Introduction
- 13.3 Features
- 13.4 Functional Description
  - 13.4.1 PIT Counter Prescaler
- 13.5 Low-Power Modes
  - 13.5.1 Wait Mode
  - 13.5.2 Stop Mode
- 13.6 PIT During Break Interrupts
- 13.7 I/O Registers
Section 14. Analog-to-Digital Converter (ADC)
- 14.1 Contents
- 14.2 Introduction
- 14.3 Features
- 14.4 Functional Description
- 14.5 Interrupts
- 14.6 Low-Power Modes
  - 14.6.1 Wait Mode
  - 14.6.2 Stop Mode
- 14.7 I/O Signals
- 14.8 I/O Registers
Section 15. Serial Communications Interface Module (SCI)
- 15.1 Contents
- 15.2 Introduction
- 15.3 Features
- 15.4 Pin Name Conventions
- 15.5 Functional Description
- 15.6 Low-Power Modes
  - 15.6.1 Wait Mode
  - 15.6.2 Stop Mode
- 15.7 SCI During Break Module Interrupts
- 15.8 I/O Signals
  - 15.8.1 PTE0/TxD (Transmit Data)
  - 15.8.2 PTE1/RxD (Receive Data)
- 15.9 I/O Registers
Section 16. Serial Peripheral Interface Module (SPI)
- 16.1 Contents
- 16.2 Introduction
- 16.3 Features
- 16.4 Pin Name Conventions and I/O Register Addresses
- 16.5 Functional Description
  - 16.5.1 Master Mode
  - 16.5.2 Slave Mode
- 16.6 Transmission Formats
- 16.7 Queuing Transmission Data
- 16.8 Error Conditions
  - 16.8.1 Overflow Error
  - 16.8.2 Mode Fault Error
- 16.9 Interrupts
- 16.10 Resetting the SPI
- 16.11 Low-Power Modes
  - 16.11.1 Wait Mode
  - 16.11.2 Stop Mode
- 16.12 SPI During Break Interrupts
- 16.13 I/O Signals
- 16.14 I/O Registers
Section 17. Input/Output (I/O) Ports
- 17.1 Contents
- 17.2 Introduction
- 17.3 Port A
  - 17.3.1 Port A Data Register (PTA)
  - 17.3.2 Data Direction Register A (DDRA)
- 17.4 Port B
  - 17.4.1 Port B Data Register (PTB)
  - 17.4.2 Data Direction Register B (DDRB)
- 17.5 Port C
  - 17.5.1 Port C Data Register (PTC)
  - 17.5.2 Data Direction Register C (DDRC)
- 17.6 Port D
- 17.7 Port E
  - 17.7.1 Port E Data Register (PTE)
  - 17.7.2 Data Direction Register E (DDRE)
- 17.8 Port F
- 17.9 Port G
  - 17.9.1 Port G Data Register (PTG)
  - 17.9.2 Data Direction Register G (DDRG)
- 17.10 Port H
  - 17.10.1 Port H Data Register (PTH)
  - 17.10.2 Data Direction Register H (DDRH)
Section 18. External Interrupt (IRQ)
- 18.1 Contents
- 18.2 Introduction
- 18.3 Features
- 18.4 Functional Description
  - 18.4.1 IRQ Pin
- 18.5 IRQ Status and Control Register (ISCR)
- 18.6 IRQ Module During Break Interrupts
Section 19. Keyboard Interrupt Module (KBI)
- 19.1 Contents
- 19.2 Introduction
- 19.3 Features
- 19.4 I/O Pins
- 19.5 Functional Description
- 19.6 Wait Mode
- 19.7 Stop Mode
- 19.8 Keyboard Module During Break Interrupts
Section 20. Computer Operating Properly (COP)
- 20.1 Contents
- 20.2 Introduction
- 20.3 Functional Description
- 20.4 I/O Signals
- 20.5 COP Control Register
- 20.6 Interrupts
- 20.7 Monitor Mode
- 20.8 Low-Power Modes
  - 20.8.1 Wait Mode
  - 20.8.2 Stop Mode
- 20.9 COP Module During Break Mode
Section 21. Low-Voltage Inhibit (LVI)
- 21.1 Contents
- 21.2 Introduction
- 21.3 Features
- 21.4 Functional Description
- 21.5 LVI Status Register (LVISR)
- 21.6 LVI Interrupts
- 21.7 Low-Power Modes
  - 21.7.1 Wait Mode
  - 21.7.2 Stop Mode
Section 22. Break Module (BRK)
- 22.1 Contents
- 22.2 Introduction
- 22.3 Features
- 22.4 Functional Description
- 22.5 Low-Power Modes
  - 22.5.1 Wait Mode
  - 22.5.2 Stop Mode
- 22.6 Break Module Registers
Section 23. Electrical Specifications
- 23.1 Contents
- 23.2 Introduction
- 23.3 Absolute Maximum Ratings
- 23.4 Functional Operating Range
- 23.5 Thermal Characteristics
- 23.6 5.0-V DC Electrical Characteristics
- 23.7 EEPROM and Memory Characteristics
- 23.8 5.0-V Control Timing
- 23.9 Timer Interface Module Characteristics
- 23.10 ADC Characteristics
- 23.11 SPI Characteristics
- 23.12 Clock Generation Module Characteristics
- 23.13 FLASH Memory Characteristics
Section 24. Mechanical Specifications
- 24.1 Contents
- 24.2 Introduction
- 24.3 64-Pin Plastic Quad Flat Pack (QFP)
Section 25. Ordering Information
- 25.1 Contents
- 25.2 Introduction
- 25.3 MC Order Numbers

Break Module (BRK)

Technical Data MC68HC908AB32 — Rev. 1.1

368 Break Module (BRK) Freescale Semiconductor

22.4.1 Flag Protection During Break Interrupts

The BCFE bit in the SIM break flag control register (SBFCR) enables

software to clear status bits during the break state.

22.4.2 CPU During Break Interrupts

The CPU starts a break interrupt by:

• Loading the instruction register with the SWI instruction

• Loading the program counter with $FFFC and $FFFD ($FEFC and

$FEFD in monitor mode)

The break interrupt begins after completion of the CPU instruction in

progress. If the break address register match occurs on the last cycle of

a CPU instruction, the break interrupt begins immediately.

22.4.3 PIT, TIMA, and TIMB During Break Interrupts

A break interrupt stops all timer counters.

22.4.4 COP During Break Interrupts

The COP is disabled during a break interrupt when V

TST

is present on

the RST pin.

22.5 Low-Power Modes

The WAIT and STOP instructions put the MCU in low power-

consumption standby modes.

22.5.1 Wait Mode

If enabled, the break module is active in wait mode. In the break routine,

the user can subtract one from the return address on the stack if SBSW

is set (see Section 8. System Integration Module (SIM)). Clear the

SBSW bit by writing logic 0 to it.