Mostek z80 - S-Step Command; Description of S Command

3.59
3.60
3-39
S-STEP CCMMAND
FORMAT:
'§. ~CR)
< Begin single-step (1)
,§.lCR)
< Continue single-step
(2)
'§. a,n(CR)
<
Begin multi-step
(3)
'§. a,n,m(CR)
<
Change display mode
(4)
DESCRIPTION,
S COMMAND
The S command is used to single-step execute instructions in Target memory.
Format (1) is used to begin single-step execution at address "s". When (CR)
is entered, the instruction at address liS" is executed and the Z80 CPU
registers are printed and the system waits in the single-step mode for one
of the following special keys to be entered.
SPECIAL KEY FUNCTION
(.) Terminate S conunand, return to monitor
(SP) Begin multi-step if suspended, suspend multi-step
if stepping.
(CR) Single Step next instruction.
Format (2) is used to continue single-step execution. 'iliis format is the
same as fonnat (1) except the begin address is taken from the program
Counter save
area register (:PC).
Format (3)
is used to begin multi-step execution. '!he first operand "a" is
the begin address and the second operand II nil is the mnnber of
instructions to execute up to 0F~~.
Note that the next instruction to be executed will also be displayed.