Zilog Z80195 User Manual
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Step (Into Subroutine Calls) [T]
This command steps a specified number of instructions, stepping “into” the subroutines and calls.
Stepping can be done in RAM and the monitor program checks for this. You can step “over” but not
“into” an RST or ROM-based subroutines. The monitor program stores an EF at the start of the
subroutine. If the user steps into a HALT or SLP instruction and no device interrupts occur to escape
this state, the user must press the NMI key to keep stepping.
Example:
Z80185 > Step How Many Instructions:
Disassemble Instructions [U]
This command disassembles a specified number of instructions from a specified starting address.
The next instruction is always disassembled whenever the registers are shown the following: R
command with no operand, breakpoint, step, and NMI. The maximum value for this command is in
the range hex 15-17 (decimal 21-23) since more that this will not fit on the screen. After disassembling
the indicated number of instructions, the monitor returns to the command prompt. If you respond with
a
where it left off. This facility is useful for “scanning through” a program looking for a particular type
of code.
Example:
Z80185>Disassemble starting at (just CR = From PC):9000
Number of Instructions:
2
9000 39 ADD HL,SP
9001 2039 JR NZ,903C
Z80185>