The 80386Dx/Dxl Inverse Assemblers - HP E2444A User Manual

The
80386DX/DXL
Inverse
Assemblers
Note
Analyzing the Intel 80386DX/DXL
2-10
The 80386DX/DXL Preprocessor Interface software contains two
inverse assemblers, IA386 and IA386E. IA386E contains additional
features which use the increased capabilities of some of the logic
analyzers (see page 1-12). For more information on the IA386E
features, see "The IA386E Inverse Assembler".
The inverse assemblers have been designed to support the
80386DX/DXL microprocessor with or without coprocessors. The
following paragraphs explain the operation of the inverse assemblers
and the results you can expect in certain conditions.
The 80386DX/DXL microprocessor can fetch instructions up to 4 bytes
(32 bits) wide in a single bus cycle. However, the microprocessor does
not indicate externally which of the bytes fetched is the first byte of a
code fetch. You must "point" to the first byte of an instruction fetch.
Once synchronized, the inverse assemblers will disassemble from this
state through the end of the screen.
In addition, the 80386DX/DXL microprocessor can execute two types
of object code. The 80386DX/DXL can execute the 80386DX/DXL
instruction set (32-bit), and it can also execute object code from Intel's
16-bit microprocessor family, including software designed for the Intel
8086 and the Intel 80286. The user must tell the logic analyzer what
"size" of code is being executed by the microprocessor.
Size, as used here, has no relationship to the physical size of the
microprocessor's data bus. In this reference, size is used to indicate
whether the code being executed was originally designed to run on
Intel's 16-bit or 32-bit microprocessors.
80386DX/DXL Preprocessor Interface
HP E2444A