mc68hc912dg128 Freescale Semiconductor, Inc, mc68hc912dg128 Datasheet - Page 355

• Manufacturer Part Number: mc68hc912dg128
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Technical Data — MC68HC912DG128
18.1 Contents
18.2 Introduction
18.3 Instruction Queue
MC68HC912DG128 — Rev 3.0
MOTOROLA
18.2
18.3
18.4
18.5
18.6
Development support involves complex interactions between
MC68HC912DG128 resources and external development systems. The
following section concerns instruction queue and queue tracking signals,
background debug mode, and instruction tagging.
The CPU12 instruction queue provides at least three bytes of program
information to the CPU when instruction execution begins. The CPU12
always completely finishes executing an instruction before beginning to
execute the next instruction. Status signals IPIPE[1:0] provide
information about data movement in the queue and indicate when the
CPU begins to execute instructions. This makes it possible to monitor
CPU activity on a cycle-by-cycle basis for debugging. Information
available on the IPIPE[1:0] pins is time multiplexed. External circuitry
can latch data movement information on rising edges of the E-clock
signal; execution start information can be latched on falling edges.
18-1
Freescale Semiconductor, Inc.
For More Information On This Product,
shows the meaning of data on the pins.
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Instruction Queue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Background Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Breakpoints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
Instruction Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382
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Development Support
Section 18. Development Support
Technical Data
Table
355