Fujitsu softune f2 mc-16 Manuel D’Utilisation

256

CHAPTER 2 DEPENDENCE FUNCTIONS

2.5.6

Real-time Trace

While execution a program, the address, data and status information, and the data
sampled by an external probe can be sampled in machine cycle units and stored in the
trace buffer. This function is called real-time trace.
In-depth analysis of a program execution history can be performed using the data
recorded by real-time trace.

■

Trace Buffer

The data recorded by sampling in machine cycle units, is called a frame.

The trace buffer can store 64K frames (65536). When the enhancing trace board is used, it becomes capacity

for 256M (268,435,456) frame.

Since the trace buffer has a ring structure, when it becomes full, it automatically returns to the start to

overwrite existing data.

■

Trace Data

Data sampled by the trace function is called trace data.

The following data is sampled:

•

Branching instruction frame

Branching source address, branching target address, disassemble

•

Data frame

Access address, Access data, Access size, Access attribute (read/write), and Bus master (CPU/DMA)

•

Special frame

Program stop, Trace start/end, Reset, Loop count, Extended time stamp frame, Data lost

•

Difference of execution time with frame immediately before (unit of CPU clock)

■

Frame Number

A number is assigned to each frame of sampled trace data. This number is called a frame number.

The frame number is used to specify the display start position of the trace buffer. The value 0 is assigned to

trace data at the triggering position for sequencer termination. Negative values are assigned to trace data that

have been sampled before arrival at the triggering position (See Figure 2.5-2).

If there is no triggering position for sequencer termination, the value 0 is assigned to the last-sampled trace

data.