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

Serial Communications Interface

Technical Data MC68HC908AB32 — Rev. 1.1

240 Serial Communications Interface Module (SCI) Freescale Semiconductor

15.8.2 PTE1/RxD (Receive Data) . . . . . . . . . . . . . . . . . . . . . . . . .260

15.9 I/O Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261

15.9.1 SCI Control Register 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . .261

15.9.2 SCI Control Register 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . .264

15.9.3 SCI Control Register 3 . . . . . . . . . . . . . . . . . . . . . . . . . . .267

15.9.4 SCI Status Register 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . .269

15.9.5 SCI Status Register 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .273

15.9.6 SCI Data Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .274

15.9.7 SCI Baud Rate Register. . . . . . . . . . . . . . . . . . . . . . . . . . .275

15.2 Introduction

This section describes the serial communications interface (SCI)

module, which allows high-speed asynchronous communications with

peripheral devices and other MCUs.

NOTE: References to DMA (direct-memory access) and associated functions

are only valid if the MCU has a DMA module. This MCU does not have

the DMA function. Any DMA-related register bits should be left in their

reset state for normal MCU operation.

15.3 Features

Features of the SCI module include the following:

• Full-duplex operation

• Standard mark/space non-return-to-zero (NRZ) format

• 32 programmable baud rates

• Programmable 8-bit or 9-bit character length

• Separately enabled transmitter and receiver

• Separate receiver and transmitter CPU interrupt requests

• Programmable transmitter output polarity