Datasheet
Table Of Contents
- List of Sections
- Table of Contents
- General Description
- Central Processing Unit (CPU)
- Pinout and Signal Description
- System Configuration
- Registers
- Operating Modes
- Resource Mapping
- Bus Control and Input/Output
- Resets and Interrupts
- Voltage Regulator (VREG)
- Flash EEPROM 256K
- EEPROM 4K
- Port Integration Module
- Clocks and Reset Generator (CRG)
- Pulse Width Modulator (PWM)
- Enhanced Capture Timer (ECT)
- Serial Communications Interface (SCI)
- Serial Peripheral Interface (SPI)
- Inter-IC Bus (IIC)
- MSCAN
- Analog to Digital Converter
- Byte Data Link Controller Module
- Contents
- Overview
- Features
- Block Diagram
- Register Map
- Functional Description
- Register Descriptions
- External Pin Descriptions
- Reset Initialization/Basic Operation
- Transmitting A Message
- Receiving A Message
- Transmitting An In-Frame Response (IFR)
- Receiving An In-Frame Response (IFR)
- Special BDLC Operations
- Modes of Operation
- Interrupt Operation
- Low Power Options
- Background Debug Module (BDM)
- Breakpoint (BKP) Module
- Revision History
- Glossary
- Literature Updates

MC9S12DP256 — Revision 1.1
Background Debug Module (BDM)
Background Debug Module (BDM)
Background Debug Module (BDM)
Contents
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 691
Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 692
Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 693
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 698
Modes of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 710
Low-Power Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 711
Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 711
Overview
The Background Debug Mode (BDM) sub-block is a single-wire,
background debug system implemented in on-chip hardware for minimal
CPU intervention. All interfacing with the BDM is done via the BKGD pin.
Features • Single-wire communication with host development system
• Active out of reset in special single-chip mode
• Nine hardware commands using free cycles, if available, for
minimal CPU intervention
• Hardware commands not requiring active BDM
• 15 firmware commands execute from the standard BDM firmware
lookup table
• Instruction tagging capability
• Software control of BDM operation during wait mode
• Software selectable clocks
Freescale Semiconductor, I
Freescale Semiconductor, Inc.
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