Event breakpoints are special onces. They cause stop of execution if event specified by the breakpoint occures. Event can be a read or a write operation on any address space location. Event breakpoint stops execution after specified event occured.
Every breakpoint can be fix (permanent) or dynamic (temporary). Dynamic breakpoints are automatically removed when they reached. Some commands place dynamic fetch breakpoints into the code, for example go or next.
A hit number can be associated to any breakpoint. This hit number specifies how many times the breakpoint must be hit before it causes the execution to stop. This hit number is 1 by default.
Fetch or event breakpoint can be defined. First form defines fetch while second form defines event breakpoint.
$ s51 remoansi.hex ucsim 0.2.24, Copyright (C) 1997 Daniel Drotos, Talker Bt. ucsim comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. 58659 bytes read from remoansi.hex > dc 0 0x10 000000 02 01 60 LJMP 0160 * 000003 02 00 3c LJMP 003c * 000006 ff MOV R7,A * 000007 ff MOV R7,A * 000008 ff MOV R7,A * 000009 ff MOV R7,A * 00000a ff MOV R7,A * 00000b 02 3b e0 LJMP 3be0 * 00000e ff MOV R7,A * 00000f ff MOV R7,A * 000010 ff MOV R7,A > break 0x160 Breakpoint 1 at 0x000160: CLR P1.0 > tbreak 8 2 Breakpoint 2 at 0x000008: MOV R7,A > g Simulation started, PC=0x000000 Stop at 000160: (4) Breakpoint F 000160 >
If parameter is not given then breakpoint at current PC will be deleted if it exists. If more than one address is specified then all breakpoints at specified addresses will be deleted.
> i b Num Type Disp Hit Cnt Address What 1 fetch keep 1 1 0x000160 CLR P1.0 2 fetch del 1 1 0x000180 LJMP 022a 1 event keep 1 1 0x000006 wi > clear 160 No breakpoint at 0000a0 > clear 0x160 > i b Num Type Disp Hit Cnt Address What 2 fetch del 1 1 0x000180 LJMP 022a 1 event keep 1 1 0x000006 wi >
If parameter is not used then all breakpoints are deleted.