3 <title>Breakpoints commands of uCsim</title>
10 <h2>Commands of uCsim to manage breakpoints</h2>
12 Two kind of breakpoints can be used: fetch and event
13 breakpoint. <B>Fetch</b> breakpoints are classical breakpoints. They
14 can be placed at any instruction in the code memory. Breakpoint will
15 be hit if CPU fetches instruction code from the memory location
16 specified by the breakpoint. Only fetching of first byte of the
17 instruction hits the breakpoint. If the execution reaches a breakpoint
18 it stops <i>before</i> the instruction at location specified by the
19 breakpoint would be executed.
21 <p><b>Event</b> breakpoints are special onces. They cause stop of
22 execution if event specified by the breakpoint occures. Events are:
24 <dl><dt><b>wi</b> <dd>writing into internal RAM at specified location;
26 <dt><b>ri</b> <dd>reading from internal RAM at specified address;
28 <dt><b>wx</b> <dd>writing into external RAM at specified location
31 <dt><b>rx</b> <dd>reading from external RAM at specified address (MOVX
34 <dt><b>ws</b> <dd>writing into SFR area at specified location;
36 <dt><b>rs</b> <dd>reading from SFR area at specified address;
38 <dt><b>rc</b> <dd>reading from code memory at specified location (MOVC
41 Event breakpoint stops execution <i>after</i> specified event occured.
43 <p>Every breakpoint can be <b>fix</b> (permanent) or <b>dynamic</b>
44 (temporary). Dynamic breakpoints are automatically removed when they
45 reached. Some commands place dynamic fetch breakpoints into the code,
46 for example <a href="#g"><b>go</b></a> or <a
47 href="#n"><b>next</b></a>.
49 <p>A <b>hit number</b> can be associated to any breakpoint. This hit
50 number specifies how many times the breakpoint must be hit before it
51 causes the execution to stop. This hit number is 1 by default.
54 <a name="break"><h3>break addr [hit]</h3></a>
55 <a name="tbreak"><h3>tbreak addr [hit]</h3></a>
57 Set fetch breakpoint. The command specifies if the breakpoint will be
58 fix (<b>break</b>) or dynamic (temporary) (<b>tbreak</b>). First
59 parameter specifies address where the breakpoint must be placed to. It
60 should be address of an instruction.
62 <p>Second parameter is optional and it specifies the hit number. It is
66 $ <font color="#118811">s51 remoansi.hex</font>
67 ucsim 0.2.24, Copyright (C) 1997 Daniel Drotos, Talker Bt.
68 ucsim comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
69 This is free software, and you are welcome to redistribute it
70 under certain conditions; type `show c' for details.
71 58659 bytes read from remoansi.hex
72 > <font color="#118811">dc 0 0x10</font>
73 000000 02 01 60 LJMP 0160
74 * 000003 02 00 3c LJMP 003c
80 * 00000b 02 3b e0 LJMP 3be0
84 > <font color="#118811">break 0x160</font>
85 Breakpoint 1 at 0x000160: CLR P1.0
86 > <font color="#118811">tbreak 8 2</font>
87 Breakpoint 2 at 0x000008: MOV R7,A
88 > <font color="#118811">g</font>
89 Simulation started, PC=0x000000
90 Stop at 000160: (4) Breakpoint
95 <a name="bse"><h3>bse wi|ri|wx|rx|ws|rs|rc f|d addr [hit]</h3></a>
97 Set event breakpoint. First parameter specifies type of event. See <a
98 href="#breakpoints">general description of event breakpoints</a> above
99 about meaning of event identifiers. Second parameter specify if the
100 breakpoint will be fix (<b>f</b>) or dynamic (<b>d</b>). Third
101 parameter specifies address. Remember that this is not an instruction
102 address, it is address of the memory cell where specified event should
105 <p>Forth parameter is optional and it specifies the hit number. It is
109 $ <font color="#118811">s51 remoansi.hex</font>
110 ucsim 0.2.12, Copyright (C) 1997 Daniel Drotos, Talker Bt.
111 ucsim comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
112 This is free software, and you are welcome to redistribute it
113 under certain conditions; type `show c' for details.
114 58659 bytes read from remoansi.hex
115 > <font color="#118811">dis</font>
117 000000 02 01 60 LJMP 0160
118 000160 c2 90 CLR P1.0
119 000162 c2 97 CLR P1.7
120 000164 d2 b5 SETB P3.5
121 000166 d2 b4 SETB P3.4
122 000168 75 81 22 MOV SP,#22
123 00016b 75 d0 00 MOV PSW,#00
124 00016e 7e 00 MOV R6,#00
125 000170 7f 00 MOV R7,#00
126 000172 79 04 MOV R1,#04
127 000174 12 0d b8 LCALL 0db8
129 000178 d9 fa DJNZ R1,0174
130 00017a 75 0b 00 MOV 0b,#00
131 00017d 75 0c 00 MOV 0c,#00
132 000180 02 02 2a LJMP 022a
133 000183 78 22 MOV R0,#22
134 000185 76 00 MOV @R0,#00
135 000187 d8 fc DJNZ R0,0185
136 > <font color="#118811">bse wi f 6</font>
137 > <font color="#118811">g</font>
139 000170 7f 00 MOV R7,#00
143 <a name="clear"><h3>clear [addr...]</h3></a>
145 Delete fetch breakpoint. Parameter specifies address of breakpoint. If
146 there is no breakpoint specified at given address this command prints
147 out a warning message.
149 <p>If parameter is not given then breakpoint at current PC will be
150 deleted if it exists. If more than one address is specified then all
151 breakpoints at specified addresses will be deleted.
154 > <font color="#118811">i b</font>
155 Num Type Disp Hit Cnt Address What
156 1 fetch keep 1 1 0x000160 CLR P1.0
157 2 fetch del 1 1 0x000180 LJMP 022a
158 1 event keep 1 1 0x000006 wi
159 > <font color="#118811">clear 160</font>
160 No breakpoint at 0000a0
161 > <font color="#118811">clear 0x160</font>
162 > <font color="#118811">i b</font>
163 Num Type Disp Hit Cnt Address What
164 2 fetch del 1 1 0x000180 LJMP 022a
165 1 event keep 1 1 0x000006 wi
169 <a name="bde"><h3>bde wi|ri|wx|rx|ws|rs|rc addr</h3></a>
171 Delete event breakpoint. First parameter must be given to specify type
172 of event. Second parameter is address of memory cell which the
173 breakpoint is associated to. Continuing example given above:
176 > <font color="#118811">bl</font>
177 D 2(2) 000180 02 LJMP 022a
179 > <font color="#118811">bde ri 6</font>
180 No ri breakpoint at 000006
181 > <font color="#118811">bde wi 6</font>
182 > <font color="#118811">bl</font>
183 D 2(2) 000180 02 LJMP 022a
187 <a name="ba"><h3>ba</h3></a>
189 Delete all breakpoints. This command deletes all fetch as well as
190 event breakpoints. Be carefull because it does not ask you to confirm
194 > <font color="#118811">bl</font>
195 F 1(1) 000160 c2 CLR P1.0
196 D 2(2) 000180 02 LJMP 022a
198 > <font color="#118811">ba</font>
199 > <font color="#118811">bl</font>