User`s guide

KA52/53/54 Firmware Commands
3.2 Console Commands
The console enters the "Spacebar Step Mode". In this mode, subsequent
spacebar strokes initiate single steps and a carriage return forces a return to
the console prompt.
The following restrictions apply:
• If memory management is enabled, the NEXT command works only if the
first page in SSC RAM is mapped in S0 (system) space.
• Overhead associated with the NEXT command affects execution time of an
instruction.
• The NEXT command elevates the IPL to 31 for long periods of time
(milliseconds) while single-stepping over several commands.
• Unpredictable results occur if the macro instruction being stepped over
modifies either the SCBB or the trace trap entry. This means that you
cannot use the NEXT command in conjunction with other debuggers.
Arguments:
{count} A value representing the number of macro instructions to execute.
Examples:
>>>DEP 1000 50D650D4 ! Create a simple program.
>>>DEP 1004 125005D1
>>>DEP 1008 00FE11F9
>>>EX /INSTRUCTION /N:5 1000 ! List it.
P 00001000 D4 CLRL R0
P 00001002 D6 INCL R0
P 00001004 D1 CMPL S^#05,R0
P 00001007 12 BNEQ 00001002
P 00001009 11 BRB 00001009
P 0000100B 00 HALT
>>>DEP PR$_SCBB 200 ! Set up a user SCBB...
>>>DEP PC 1000 ! ...and the PC.
>>>
>>>N ! Single step...
P 00001002 D6 INCL R0 ! SPACEBAR
P 00001004 D1 CMPL S^#05,R0 ! SPACEBAR
P 00001007 12 BNEQ 00001002 ! SPACEBAR
P 00001002 D6 INCL R0 ! CR
>>>N5 ! ...or multiple step the program.
P 00001004 D1 CMPL S^#05,R0
P 00001007 12 BNEQ 00001002
P 00001002 D6 INCL R0
P 00001004 D1 CMPL S^#05,R0
P 00001007 12 BNEQ 00001002
>>>N7
P 00001002 D6 INCL R0
P 00001004 D1 CMPL S^#05,R0
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