HP E2470A, Manual

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Using the Inverse Assembler
This section discusses the general output format of the inverse
assembler and controller-specific information. This section also
assumes that an inverse assembler has been loaded.
General Output Format
The next few paragraphs describe the general output format of the inverse
assembler.
Numeric Format
Unless a value is followed by a suffix character, numeric output from the
inverse assembler is in hexadecimal format. For example, decimal values
have a period (.) as the suffix character; binary values have a percent sign
(%) prefix.
Missing Opcodes/Operands
Asterisks (*) in the inverse assembler output indicate missing operands.
Missing operands occur frequently and are primarily due to microcontroller
prefetch activity. Storage qualification or the use of storage windows can
also lead to such occurrences.
Don’t Care Bytes
The MC68HC16Y1 microcontroller can perform 3-byte transfers. During
operand reads and writes, 16-bit (word) values appear on the microcontroller
data bus lines. The inverse assembler will attempt to display "xx" for any byte
in a transfer that is ignored by the microcontroller. You can then determine
exactly which byte or bytes of data were used as an operand. If the
microcontroller is configured such that the number of bytes being transferred
cannot be determined, an entire word will be displayed. The user must then
determine which byte(s) is valid.
Unexecuted Prefetched Instructions
Prefetched instructions which are not executed by the microcontroller are
marked by a hyphen "-" in the first column of the mnemonic/hex field.
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