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CHAP5
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CHAPTER 5
Using Other Commands
5.1 Display and Edit Commands
5.2 I/O Port Commands
5.3 Transfer Control Commands
5.4 Debug Mode Commands
5.5 Utility Commands
5.6 Specialized Debugging Commands
5.7 Windowing Commands
5.8 Debugger Customization Commands
5.9 Screen Control Commands
5.10 Symbol and Source Line Commands
5.1 Display and Edit Commands
75
Commands:
U -- Unassemble instructions or display source
R -- Display or change registers
MAP -- Display system memory map
D -- Display memory in the most recently
specified format
DB -- Display memory in byte format
DW -- Display memory in word format
DD -- Display memory in double word format
E -- Edit memory in the most recently
specified format
EB -- Edit memory bytes
EW -- Edit memory words
ED -- Edit memory double words
INT? -- Display last interrupt number
? or H -- Display help information
VER -- Display Soft-ICE version number
76
U
U -- Unassemble instructions or display source
Syntax :
U [address] [L[=]length]
length -- The number of instructions
to be unassembled
Comments:
The U command displays the instructions of the program being debugged.
If length is not specified, the length defaults to eight lines if
available, or one less than the screen length.
If address is not specified, the command unassembles at address starting
at the first byte after the last byte unassembled by a previous unassemble
command. If the has been no previous unassemble command, the address
defaults to the current CS:IP.
If the code window is visible, the instructions are displayed in the code
window.
If source is loaded for the address range specified then source lines may
be displayed depending on the current source mode.
Example:
U $-10
This command unassembles instructions beginning
10 hexadecimal bytes before the current address.
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U .499
This command displays the current source file starting at line 499. The
code window must be visible and in source mode.
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R
R-- Display or change registers
Syntax:
R register-name [ [ = ]value] ]
register-name -- Any of the following:
AL, AH, AX, BL, BH,
BX, CL, CH, CX, DL,
DH, DX, DI, SI, BP,
SP, IP, CS, DS, ES, SS,
or FL
value -- If register-name is any name other than
FL, value is a hex value or an
expression. If register-name is FL,
value is a series of one or more of the
following flag symbols, each
optionally preceded by a plus or
minus sign:
O (Overflow flag)
D (Direction flag)
I (Interrupt flag)
S (Sign flag)
Z (Zero flag)
A (Auxiliary carry flag)
P (Parity flag)
C (Carry flag)
Comments:
The R command displays or changes register values.
If no parameters are supplied, all register and flag value are displayed,
as well as the instruction at the current CS:IP address.
If register-name is supplied without a value, Soft-ICE displays the
current value of the specified register and
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prompts you for a new value. If register-name is FL, flags that are set
are displayed as highlighted uppercase characters; flags that are cleared
are displayed as non-highlighted lowercase characters. To retain the
current value of a register, press ENTER.
If both register-name and value are supplied, the specified register's
contents are changed to the value.
To change a flag value, use FL as the register-name, followed by the
symbols of the flag whose values you want to toggle. To turn a flag on,
precede the flag symbol with a plus sign. To turn a flag off, precede the
flag symbol with a minus sign. The flags can be listed in any order.
Examples:
RAH 5
This command sets the AH register equal to 5.
R FL = OZP
This command toggles the O, Z, and P flag values.
R FL
This command displays the current flag values, and
allows them to be changed.
RFL O + A-C
This command toggles the O flag value, turns on the
flag value, and turns off the C flag value.
80
MAP
MAP -- Display system memory map
Syntax :
MAP
Comments:
The MAP command displays the names, locations, and sizes of system memory
components. The size is displayed in paragraphs. One paragraph is
equivalent to 10 hexadecimal bytes.
The component that the CS:IP register currently points to is highlighted.
Use the MAP command when:
* A break point occurs and CS:IP is not in a known
memory region.
* You want to get control within a resident program
or system program. A range break point can be set
based on the starting address and size reflected by
MAP.
* You suspect a program or system component of
writing over code outside of its memory space.
MAP is used to obtain the memory address of the
region to use with the CSIP command.
* You need to find out which resident program owns
certain interrupt vectors.
81
Example:
MAP
The following is a sample display produced by the
command:
Start Length
0000:0000 0040 Interrupt Vector Table
0040:0000 0030 ROM BIOS Variables
0070:0000 00FE I/O System
016E:0000 06B7 DOS
0842:0000 02CE DOS File Table & Buffers
A000:0000 5E00 System BUS
F000:0000 1000 ROM BIOS
Versions of DOS lower than 3.1 display program
addresses instead of displaying the program names.
82
D, DB, DW, DD
D, DB, DW, DD -- Display memory
Syntax:
D [size] [address] [L[ = ]length]
size -- B -- Byte
W -- Word
D -- Double Word
length -- The number of bytes to be
displayed.
Comments:
The D command displays the memory contents of the specified address.
The contents are displayed in the format of the size specified. If no size
is specified, the last size used will be displayed. The ASCII
representation is also displayed for all forms.
If address is not specified, the command displays memory at the address
starting at the first byte after the last byte displayed.
If length is not specified, it defaults to eight lines, or fewer if the
window is smaller.
If the data window is visible, the data is displayed in the data window
and the length is ignored.
Example:
DW DS:00 L=8
This command displays, in word format and in ASCII
format, the value of the first eight bytes of the current
data segment.
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E, EB, EW, ED
E, EB, EW, ED -- Edit memory
Syntax:
E [size ] address [data-list]
size -- B -- Byte
W -- Word
D -- Double Word
data-list -- list of data objects of the specified size
(Bytes, Words or Double Words) or
quoted strings separated by commas
or spaces. The quoted string can
begin with a single quote or a double
quote.
Comments:
The E commands display the memory contents at the specified address, and
allow you to edit the values.
These commands display the memory contents in ASCII format, and in the
format of the size specified.
A memory editor is provided for quick memory updates. Memory can be edited
by typing ASCII characters, or by typing byte, word, or double word
values. If no size is specified, the last size used will be assumed. The
memory Editing key strokes are:
@ -- Move cursor up
@ -- Move cursor down
@ -- Move cursor right
@ -- Move cursor left
SPACE -- Move cursor to next element
84
TAB -- Toggle between numeric and
ASCII areas
ESC or
ENTER -- Exit memory editor
As values are input, the actual memory locations are updated. All numeric
values are hex numbers. To toggle between the ASCII and numeric display
areas, press the TAB key.
If the data window is visible, the data is edited in the data window,
otherwise the data is edited in the command window.
The data display length defaults to 8 lines if in the command window, or
to the size of the data window if it's visible.
If no parameters are supplied, the cursor moves into the data window if
the data window if visible. If the data window is not visible, the data is
edited in the command window at the last address displayed or edited.
Examples:
EB 1000:0
This command displays, in byte format, up to six lines
containing both the numeric and the ASCII
representation of the values of the data starting at
location 1000:0000. Once the lines are displayed, you
can edit the values.
EB 8000:0 "Hello",0D
This command replaces the values starting at locatio
8000:0000 with the string "Hello" followed by a carriage
return.
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INT?
INT? -- Display last interrupt number
Syntax:
INT?
Comments:
The INT? command displays the address and the number the last interrupt
that happened.
Example:
INT?
An example of the display produced by the INT?
command follows:
Last Interrupt: 16
At: 0070:0255
This example shows that the last interrupt generated in
the system before the Soft-ICE window was brought up
was an interrupt 16 hexadecimal, at location
0070:0255H. If the last interrupt that happened was a
software interrupt, unassembling the code at
0070:0255H will show the interrupt instruction. If it
was a hardware interrupt, unassembling the code will
show the instruction that was executing when the
hardware interrupt occurred.
86
? or H
? or H -- Display help information
Syntax:
< ? | H > [command | expression]
Comments:
The ? command and the H command both display help information.
If no parameters are specified, help displays short descriptions of all
the commands and operators, one screen at a time. Press any key to
continue, or press ESC to quit displaying help.
If command is specified, help displays more detailed information on the
specified command, including the command syntax and an example.
If expression is specified, the expression is evaluated and the result is
displayed in hexadecimal, decimal, and ASCII.
Examples:
? ALTKEY
This command displays information about the
ALTKEY command, including its syntax and an
example.
H 10 + 14*2
This command displays: 0038 00056 "8". These are the
hexadecimal, decimal and ASCII representations of
value of the expression "10 + 14*2".
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VER
VER -- Display Soft-ICE version number
Syntax:
VER
Example:
VER
This command displays the Soft-ICE version
and the Nu-Mega Technologies copyright message.
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5.2 I/O Port Commands
Commands:
I or IB -- Input from byte I/O port
IW -- Input from word I/O port
O or OB -- Output to byte I/O port
OW -- Output to word I/O port
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I, IB, IW
I, IB, IW -- Input from I/O port
Syntax:
I [size] port
Size -- B -- Byte
W -- Word
port -- A byte or word value
Comments:
The input from port commands are used to read and display a value from a
hardware port. Input can be done From byte or word ports. If no size is
specified, the default is byte.
Example:
I 21
This command displays the mask register for interrupt
controller one.
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O, OB, OW
O, OB, OW, -- Output to I/O port
Syntax:
O [size] port value
size -- B -- Byte
W -- Word
port -- A byte or word value
value -- A byte for a byte port or a word
for a word port
Comments:
The output to port commands are used to write a value to a hardware port.
Output can be done to byte or word ports If no size is specified, the
default is byte.
Example:
O 21 FF
This command masks off all the interrupts for interrupt
controller one.
91
5.3 Transfer Control Commands
Commands:
X -- Exit from Soft-ICE window
G -- Go to address
T -- Trace one instruction
P -- Program step
HERE -- Go to current cursor line
GENINT -- Force an interrupt
EXIT -- Force exit of current DOS program
BOOT -- System boot (retain Soft-ICE)
HBOOT -- Hard system boot (total reset)
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X
X -- Exit from Soft-ICE window
Syntax:
X
Comments:
The X command exits the Soft-ICE window and restores control to the
program that was interrupted to bring up Soft-ICE. The Soft-ICE window
disappears. If any break points have been set, they become active.
Example:
X
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G
G -- Go to address
Syntax:
G [=start-address] [break-address]
Comments:
The G command exits from the Soft-ICE window with a single one-time
execution break point set. In addition, all sticky break points are armed.
Execution begins at the current CS:IP unless the start-address parameter
is supplied. In that case execution begins at start-address. Execution
continues until break-address is encountered, the window pop-up key
sequence is used, or a sticky break point occurs.
The break-address must be the first byte of an instruction opcode.
When the specified break-address is reached, the current CS:IP will be the
instruction where the break point was set.
The G command with no parameters behaves the same as the X command.
The non-sticky execution break point uses an 80386 break point register,
unless all break point registers have been allocated to sticky break
points. In that case, an INT 3 style break point is implemented. When this
case occurs, the G and P commands will not work correctly in ROM. An error
message will be displayed if this is attempted.
Example:
G CS:1234
This command sets a one time break point at CS:1234
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T
T -- Trace one instruction
Syntax:
T [=start-address] [count]
Comments:
The T command single steps one instruction by utilizing the single step
flag.
Execution begins at the current CS:IP unless the start-address parameter
is specified. If start-address is specified, CS:IP is changed to start-
address prior to single stepping.
If count is specified then Soft-ICE single steps count time The TRACE
command will continue until the count is exhausted or the Esc key is
pressed, regardless of which break points are reached.
In source mode, the T command steps to the next source statement. If the
current statement is a procedure or function call, and source exists for
the routine being called, T steps into the call. If there is no source
available for the called procedure or function, T steps over the routine.
Example :
T = 1284 3
This command single steps through three instruction
starting at memory location 1284.
95
P
P -- Program step
Syntax:
P
Comments:
The P command is a logical program step. One instruction at the current
CS:IP is executed unless the instruction is a call, interrupt, loop, or
repeated string instruction. In those cases, the entire routine or
iteration is completed before control is returned to Soft-ICE.
The P command uses a one-time execution break point. The non-sticky
execution break point uses an 80386 break point register, unless all break
point registers have been allocated to sticky break points. In that case,
an INT3 style break point is implemented. When this case occurs, the P and
G commands will not work correctly in ROM. An error message will be
displayed if this is attempted.
In source mode, the P command steps to the next source statement. If the
current statement is a procedure or function call, the P command steps
over the it.
Example:
P
This command executes one 'program step'.
96
HERE
HERE -- Go to current cursor line
Syntax:
HERE
Comments:
The HERE command executes until the program reaches the current cursor
line. HERE is only available when the cursor is in the code window. If the
code window is not visible or the cursor is not in the code window, use
the G command instead.
The HERE command exits from Soft-ICE with a single one-time execution
break point set. In addition, all sticky break points are armed.
Execution begins at the current CS:IP and continues until address of the
current cursor position in the code window encountered, the window pop-up
key sequence is used, a sticky break point occurs.
The non-sticky execution break point uses an 80386 break point register,
unless all break point registers have been allocated to sticky break
points. In that case, an INT 3 style break point is implemented. When this
case occurs, the HERE command will not work correctly in ROM. An error
message will be displayed if this is attempted.
Example:
HERE
This example sets an execution break point at the
current cursor position, then exits from Soft-ICE and
begins execution at the current CS:IP.
Default Function Key: F7
97
GENINT
GENlNT -- Force an interrupt
Syntax:
GENINT INT1 | INT3 | NMI | interrupt-number
interrupt-number -- a number in the range 00 - FF
Comments:
The GENINT command forces an interrupt to occur. This function can be used
to hand off control to another debugger when using Soft-ICE with another
software debugger. It can also be used to test interrupt routines.
The GENINT command simulates the processing sequence of a hardware
interrupt or an INT instruction. It pushes the flags, the CS register, and
the IP register, then changes the value of the CS and IP registers to the
value of the interrupt vector table entry corresponding with the specified
interrupt number.
Example:
GENINT NMI
This forces a non-maskable interrupt. This will give
control back to CodeView if Soft-ICE is being used as
an assistant to CodeView.
98
EXIT
EXIT -- Force exit of current DOS program
Syntax:
EXIT [R] [D]
R -- Restore the interrupt vector table
D -- Delete all break points
Comments:
The EXIT command attempts to abort the current program by forcing a DOS
exit function (INT 21H, function 4CH) This command will only work if the
DOS is in a state where it is able to accept the exit function call. If
this call is made from certain interrupt routines, or other times when the
DOS is not ready, the system may behave unpredictably.
This function does NOT do any system resetting other than the interrupt
table when the R option is used. This means that BIOS variables, video
modes and other systems level data are not restored.
Using the R option will cause the interrupt vectors to be restored to
whatever they were the last time they were saved. Soft-ICE saves the
interrupt vectors when it is loaded, when a program is loaded with
LDR.EXE, and when the VECS S command is used.
Note:
To re-start a program that has been loaded with the Soft-ICE program
loader (LDR.EXE) do the following:
EXIT R
LDR prog.EXE
The EXIT command will restore the interrupt table to the values it
contained before the program was loaded, then
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exit to the command processor. By running the LDR utility and specifying
the .EXE suffix, the program is loaded back in without re-loading symbols
and source. The symbols and source will remain in memory.
Caution:
The EXIT command should be used with care. Since Soft-ICE can be popped up
at any time, a situation can occur where the DOS is not in a state to
accept an exit function call. Also, the EXIT command does not do any
program specific resetting. For instance, the EXIT command does not reset
the video mode. If your program has placed the video BIOS and hardware in
a particular video mode, it will stay in that mode after the EXIT command.
Example:
EXIT R
Restores the interrupt table and exits the current
program. The R option should be used if exiting from
a program loaded with the Soft-ICE program loader
LDR.EXE.
100
BOOT
BOOT -- System boot (retain Soft-ICE)
Syntax:
BOOT
Comments:
The BOOT command resets the system and retains Soft-ICE. BOOT is required
to debug boot sequences, DOS loadable drivers, and non-DOS operating
systems.
BOOT is implemented with an Interrupt 19H ROM BIOS call. In some instances
memory may be corrupted to the point where Interrupt 19 will not work. If
this occurs, bring up Soft-ICE and use the HBOOT command.
For BOOT to work properly, Soft-ICE should be installed as a loadable
driver in CONFIG.SYS before any other device drivers. This is so Soft-ICE
can restore the original system state as accurately as possible.
Example:
BOOT
This command makes the system reboot. Soft-ICE
remains resident.
101
HBOOT
HBOOT -- Hard system boot (total reset)
Syntax:
HBOOT
Comments:
The HBOOT command resets the entire system. Soft-ICE is not retained in
the reset process. HBOOT is sufficient unless an adapter card requires a
power-on reset. In those rare cases, the machine power must be recycled.
Example :
HBOOT
This command makes the system reboot. Soft-ICE
must be reloaded.
102
5.4 Debug Mode Commands
Commands:
ACTION -- Set action after break point is reached
WARN -- Set DOS/ROM BIOS re-entrancy
warning mode
BREAK -- Break out any time
I3HERE -- Direct Interrupt 3's to Soft-ICE
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ACTION
ACTION -- Set action after break point is reached
Syntax:
ACTION [INT1 | INT3 | NMI | HERE | int-number]
int-number -- Any valid interrupt number (0-FFH).
Use this option only if a user-supplied
break point qualification routine has
taken over that interrupt vector (see
section 11.2).
Comments:
The ACTION command determines where control is given when break point
conditions have been met. In most cases, the desired action is INT3 or
HERE, INT3 is typically used if Soft-ICE is being used with a host
debugger, HERE is used when it is desired to return to Soft-ICE when break
point conditions have been met, INT1 and NMI are alternatives for certain
debuggers that will not work with the INT3 option. For instance, CODEVIEW
works best with ACTION set to NMI.
Use int-number if there is a user-supplied break point qualification
routine installed. Using int-number without having a user-supplied break
point qualification routine installed causes an error. For more
information, see section 11.2,'User-Qualified Break Points'.
If no parameter is supplied with the ACTION command, the current action is
displayed.
The default action is HERE.
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Example:
ACTION HERE
This command specifies that control will return to Soft-ICE when break
point conditions have been met.
105
WARN
WARN -- Set DOS/ROM BIOS re-entrancy warning mode
Syntax:
WARN [ON | OFF]
Comments:
The WARN command is provided for using Soft-ICE with debuggers that use
DOS and ROM BIOS. Many debuggers use DOS and ROM BIOS for screen output
and for receiving keystrokes. Since DOS and ROM BIOS are not fully re-
entrant, these debuggers may not work properly if break point occurs while
the DOS or ROM BIOS is executing.
If WARN ON is set, and ACTION is not HERE, then control will come to Soft-
ICE before the actual action occurs. The system displays the current CS:IP
and gives you the choice of continuing or returning to Soft-ICE.
Generally, you should choose to return to Soft-ICE to continue your
debugging. Only continue with the host debugger if you know your debugger
will not cause DOS or ROM BIOS to be re-entered.
WARN mode should be turned on to use Soft-ICE with DEBUG, SYMDEB, and
CODEVIEW.
If no parameter is specified, the current state of WARN is displayed.
The default is WARN mode OFF.
Example:
WARN ON
This command turns on DOS/ROM BIOS re-entrancy
warning mode.
106
BREAK
BREAK -- Break out any time
Syntax:
BREAK [ON | OFF]
Comments:
The BREAK command allows popping up the Soft-ICE window when the system is
hung with interrupts disabled. Break mode can be used for the entire
debugging session, or it can be turned on and off when it is required.
Break mode degrades system performance slightly. This performance
degradation must be weighed against the necessity of breaking out of a
hung program. A user may want to have break mode on all the time, even
though performance is degraded, because the program could hang at any
time.
Unlike other debuggers that can also be brought up at any time, Soft-ICE
does not require an external switch. When BREAK is on, the Soft-ICE window
can be brought up at any time by pressing the current key sequence.
If no parameter is specified, the current state of BREAK is displayed.
The default is BREAK mode OFF.
Example:
BREAK ON
This command turns on break mode. This means that
the Soft-ICE window can be brought up at any time,
even if interrupts are disabled.
107
13 HERE
13HERE -- Direct Interrupt 3's to Soft-ICE
Syntax:
13HERE [ON | OFF]
Comments:
The 13HERE command lets you specify that any Interrupt 3 will bring up the
Soft-ICE window. This feature is useful for stopping your program in a
specific location.
To use this feature, place an INT 3 into your code at the location where
you want to stop. When the INT 3 occurs, it will bring up the Soft-ICE
window. At this point, you can use the R IP command to change your
instruction pointer to the instruction after the INT 3, then you can
continue debugging.
If no parameter is specified, the current state of 13HERE is displayed.
The default is 13HERE mode OFF.
Example:
13HERE ON
This command turns on 13HERE mode. Any INT 3's
generated after this point will bring up the Soft-ICE
window.
108
5.5 Utility Commands
Commands:
A -- Assemble code
S -- Search for data
F -- Fill memory with data
M -- Move data
C -- Compare two data blocks
109
A
A -- Assemble code
Syntax:
A [address]
Comments:
The Soft-ICE assembler allows you to assemble instructions directly into
memory. The assembler supports the basic 8086 instruction set with the
80186 and 80286 real address mode extensions. Numeric co-processor
instructions and 80386 specific instructions, registers and addressing
modes can NOT be assembled.
The A command enters the Soft-ICE interactive assembler. An address is
displayed as a prompt for each assembly line After an assembly language
instruction is typed in and ENTER is pressed, the instructions are
assembled into memory at the specified address. Instructions must be
entered with standard Intel format. Press ENTER at an address prompt to
exit assembler mode.
If the address range in which you are assembling instructions is visible
in the code window, the instructions will change interactively as you
assemble.
The Soft-ICE assembler supports the standard 8086 family mnemonics,
however there are some special additions :
* The DB mnemonic is used to define bytes of data
directly into memory. The DB command is
followed by a list of bytes and/or quoted strings
separated by spaces or commas.
* The RETF mnemonic represents a far return.
* WORD PTR and BYTE PTR are used to
determine data size if there is no register
110
argument, for example: MOV BYTE PTR
ES:[ 1234],1.
* Use FAR and NEAR to explicitly assemble far and
near jumps and calls. If FAR or NEAR is not
specified then all jumps and calls are near.
* Operands referring to memory locations should
placed in square brackets, for example: MOV
AX,[1234].
Example:
A CS:1234
This command prompts you for assembly instruction
then assembles them beginning at offset 1234H with
the current code segment. Press ENTER at the
address prompt after entering the last instruction.
111
S
S -- Search for data
Syntax:
S address L length data-list
data-list -- list of bytes or quoted strings separated
by commas or spaces. .A quoted string
can begin with a single quote or a
double quote.
length -- length in bytes
Comments:
The S command searches memory for a series of bytes or characters that
matches the data-list. The search begins at the specified address and
continues for the length specified. The address of each occurrence found
in the range is displayed.
Example:
S DS:SI+10 L CX 'Hello',12,34
This command searches for the string 'Hello' followed
by the bytes 12H and 34H starting at offset SI+10 in
the current data segment and ending CX bytes later.
112
F
F -- Fill memory with data
Syntax:
F address L length data-list
data-list -- list of bytes or quoted strings separated
by commas or spaces. A quoted string
can begin with a single quote or a
double quote.
length -- length in bytes
Comments:
The F command fills memory with the series of bytes or characters
specified in the data-list. Memory is filled starting at the specified
address and continuing for the specified length, repeating the data-list
if necessary.
Example:
F 8000:0 L 100 'Test'
This command fills memory starting at 8000:0 for a
length of 100H bytes with the string 'Test'. The string
'Test' is repeated until the fill length is exhausted.
113
M
M -- Move data
Syntax:
M start-address L length end-address
length -- length in bytes
Comments:
The M command moves the specified number of bytes from the start-address
in memory to the end-address in memory.
Example:
M 1000:0 L 200 2000:0
This command moves 200H bytes from memory
location 1000:0 to memory location 2000:0.
114
C
C -- Compare two data blocks
Syntax:
C address1 L length address2
length -- length in bytes
Comments:
The C command compares the memory block specified by address1 and the
length with the memory block specified address2 and the length.
When a byte from the first data block does not match a byte from the
second data block, both bytes are displayed, along with their addresses.
Example:
C 5000:100 L 10 6000:100
This command compares the 10H bytes starting at
memory location 5000:100 with the 10H bytes starting
at memory location 6000:100.
115
5.6 Specialized Debugging Commands
Commands:
SHOW -- Display instructions from history buffer
TRACE -- Enter trace simulation mode
XT -- Single step in trace simulation mode
XP -- Program step in trace simulation mode
XG -- Go to address in trace simulation mode
XRSET -- Reset back trace buffer
VECS -- Save/restore/compare interrupt vectors
SNAP -- Take snap shot of memory block
EMMMAP -- Display EMM allocation map
116
SHOW
SHOW -- Display instructions from history buffer
Syntax:
SHOW [B | start]
B -- This tells the show command to start
the display with the oldest instruction
in the back trace buffer.
start -- The number of instructions back from
the buffer end (last instruction
captured) to begin display.
Comments:
The SHOW command displays instructions from the back trace history buffer.
If source is available for the instructions then the display is in mixed
mode, otherwise only code is displayed.
SHOW allows scrolling through the back trace buffer with the up, down,
Pageup and PaqeDn keys. To exit from SHOW you must press the Esc key.
Preceding the address of each instruction is the buffer entry number. This
number shows how deep into the buffer you are displaying. The higher the
number, the deeper you are into the buffer.
Note:
Before using the SHOW command, instructions must have been logged with a
back trace range. See chapter 9 for more information on back trace ranges.
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Hints:
It is often useful to have the code window visible with the actual code of
the region you are displaying from the back trace buffer. When you compare
the actual instruction flow to code, displayed jumps and calls are usually
less confusing.
Using SHOW in conjunction with the TRACE command will allow you to see the
instructions in the back trace history buffer from two different points of
view.
Example:
SHOW 40
This example will displays starting with the 40th
instruction back in the back trace buffer.
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TRACE
TRACE -- Enter trace simulation mode
Syntax:
TRACE [start] | [OFF]
start -- The number of instructions back from
the buffer end (last instruction
captured) to begin trace simulation
OFF -- Exit trace simulation mode.
Comments:
The TRACE command allows you to replay instructions from the instruction
back trace history buffer just as if they were being executed for the
first time. To use trace simulation mode you must have the code window
visible After entering trace simulation mode you use the XT, XP and XG
commands to trace through the instructions in the buffer.
To exit trace simulation mode type TRACE OFF.
TRACE with no parameters specified displays whether trace simulation mode
is on or off.
Note:
Before using the TRACE command, instructions must have been logged with a
back trace range. See chapter 9 for more information on back trace ranges.
Hints:
Trace simulation mode is most useful when the code window is visible. It
is often useful to use TRACE in conjunction with the SHOW command. This
allows the
119
instructions in the back trace history buffer to be viewed simultaneously
in two different forms.
Example:
TRACE 40
This example enters trace simulation mode starting 40
instructions back from the last instruction logged. It
will remain in trace simulation mode until TRACE
OFF is entered.
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XT
XT -- Single step in trace simulation mode
Syntax:
XT [R]
R -- Single step in reverse direction.
Comments:
The XT command single steps through the instruction back trace history
buffer. This command acts like the T command for normal debugging. Note
that the registers do NOT change while stepping in trace simulation mode
except CS and IP,
The XT instruction allows you to replay instructions from the back trace
history buffer,
Note:
Before using XT you must be in trace simulation mode. See chapter 9 and
the TRACE command in this section for more information on back trace
ranges.
Hint:
If you are using XT frequently, like any other Soft-ICE command it can be
assigned to a function key.
Example:
XT
This command single steps one instruction in trace
simulation mode.
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XP
XP -- Program step in trace simulation mode
Syntax:
XP
Comments:
The XP command does a logical program step through the instruction back
trace history buffer. This command acts like the P command for normal
debugging. Note that the registers do NOT change while stepping in trace
simulation mode except CS and IP.
The XP instruction allows you to replay instructions from the back trace
history buffer.
Note:
Before using XP you must be in trace simulation mode. See chapter 9 and
the TRACE command in this section for more information on back trace
ranges.
Hint:
If you are using XP frequently, like any other Soft-ICE command it can be
assigned to a function key.
Example:
XP
This command executes one program step in trace
simulation mode.
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XG
XG -- Go to an address in trace simulation mode
Syntax:
X [R] address
R -- Search for address in reverse direction.
address -- Address to go to in the back trace
history buffer.
Comments:
The XG command moves the instruction pointer to the next occurrence of the
specified address in the back trace history buffer. If R is specified
preceding the address, then the instruction pointer is moved to the
previous occurrence the specified address in the back trace buffer.
The address must be the first byte of an instruction opcode.
The XG is analogous to the G command in normal debugging.
Note:
Before using XG you must be in trace simulation mode. See chapter 9 and
the TRACE command in this section for more information on back trace
ranges.
Example:
XG 273:1030
This command moves the instruction pointer to the
next instance of the instruction at address 273:1030.
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XRSET
XRSET -- Reset back trace history buffer
Syntax:
XRSET
Comments:
The XRSET command resets the back trace history buffer. This command
should be executed before setting a back trace range if there is unwanted
instruction information in the back trace buffer.
Example:
XRSET
This command resets the back trace buffer.
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VECS
VECS -- Save/restore/compare interrupt vectors
Syntax:
VECS [C|S|R]
C -- Compare current table with stored table
S -- Save current interrupt table to buffer
R -- Restore interrupt table from buffer
Comments:
The VECS command allows you to save and restore the interrupt table to an
internal Soft-ICE buffer. The actual table can also be compared to the
stored table with the differences displayed.
When the C option is used to compare the current interrupt vector table
with the stored copy the output is in the following format:
address old-vector new-vector
Each vector that has changed is displayed.
The interrupt vector table is initially stored when Soft-ICE is loaded. It
is also automatically stored when a program loaded with LDR.EXE. Only one
copy of the interrupt vector table is stored, so each time VECS S is
executed, previous copy of the interrupt table is overwritten.
If no parameters are specified, the entire interrupt vector table is
displayed.
125
Example:
VECS C
This command compares the actual interrupt vector
table with one that had been previously stored in the
Soft-ICE internal VECS buffer.
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SNAP
SNAP -- Take snap shot of memory block
Syntax:
SNAP [C | S | R] address1 address2
C -- Compare buffer with address range
S -- Save address range to buffer
R -- Restore buffer to address range
Comments:
The SNAP command takes a snap shot of a memory block for later comparison.
The S option copies a block of memory to a buffer in extended memory. The
C option displays differences between the buffer in extended memory and
the actual memory specified by the address range. The R option copies the
buffer in extended memory to the address range in conventional memory.
When the C option is used to compare the buffer with the address range the
output is in the following format:
address old-data new-data
Each byte that has changed is displayed.
The address is usually not necessary for the C and R options. If the
address is not specified, the address from the last time SNAP was entered
with a specified address used.
Notes:
To use the SNAP command you must have specified the /TRA XXXX switch on
the S-ICE.EXE line in CONFIG.SYS.
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The SNAP command saves data in the back trace history buffer. If you are
using back trace then you will have a conflict with SNAP. Specifically,
SNAP will overwrite back trace information if you do a SNAP S when
instruction history is in the back trace buffer. Conversely, if you have
saved a region with SNAP, then enabling a back trace range will overwrite
the SNAP buffer.
Example:
SNAP S 2000:0 4000:0
This command stores the data block from 2000:0 to
4000:0 in the Soft-ICE back trace buffer.
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EMMMAP
EMMMAP -- Display EMM allocation map
Syntax:
EMMMAP
Comments:
The EMMMAP command displays each physical page that is available for EMM
memory and the pages that are currently mapped in.
Note:
The Soft-ICE EMM feature must be enabled to use this function. See chapter
8 for more information on enabling EMM capability.
Example:
EMMMAP
This example displays the current EMM allocation in
in the following form.
Phy page Seg address Handle/Page
00 D000 FFFF
01 D400 0001/0000
02 D800 0001/0001
03 DC00 0001/0002
In this example, physical page 0 is located at D000 and
is unmapped. Physical page 1 is located at D400 and
has handle 1, page 0 mapped into it. Physical page 2 is
located at D800 and has handle 1, page I mapped into
it. Physical page 3 is located at DC00 and has handle
page 2 mapped into it.
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5.7 Windowing Commands
Commands:
WR -- Toggle register window
WC -- Toggle/set size of code window
WD -- Toggle/set size of data window
EC -- Enter/exit code window
. -- Locate current instruction
Three window types may be created with Soft-ICE:
register, data, and code. Any of these windows can be
toggled on or off at any time. The data and code
windows can be of variable size; the register window is
fixed in size. The windows always remain in a fixed
order. Starting from the top of the screen, the order is
register window, data window, then code window.
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WR
WR -- Toggle register window
Syntax:
WR
Comments:
The command makes the register window visible if not currently visible. If
the register window is currently visible, WR removes the register window.
The register window displays the 8086 register set and the processor
flags.
Default Function: F2
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WC
WC -- Toggle/set size of code window
Syntax:
WC [window-size]
window-size -- a decimal number between one and 21.
Comments:
If window-size is not specified, this command toggles the code window. If
it was not visible it is made visible, and if it was visible it is
removed.
If window-size is specified the code window is resized, or it was not
visible it is made visible with the specified size.
Note:
If you wish to move the cursor to the code window use the EC command. See
description of the EC command for more details.
Example:
WC 12
If no code window is present, then a code window 12
lines in length is created. If the code window is
currently on the screen, it is resized to 12 lines.
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WD
WD -- Toggle/set size of data window
Syntax:
WD [window-size]
window-size -- a decimal number between one and 21.
Comments:
If window-size is not specified, this command toggles the data window. If
it was not visible it is made visible, and if it was visible it is
removed.
If window-size is specified the data window is resized, or it was not
visible it is made visible with the specified size.
Example:
WD 1
If no data window is present then a data window of one
line is created. If the data window is currently on the
screen, it is resized to one line.
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EC
EC -- Enter/exit code window
Syntax:
EC
Comments:
The EC command toggles the cursor location between the code window and the
command window. If the cursor was in the command window it is moved to the
code window, and if the cursor was in the code window it is moved to the
command window.
When the cursor is in the code window several options become available
that make debugging much easier. The options are:
* Point-and-shoot break points
Point-and-shoot break points are set with the BP
command. If no parameters are specified with the
BPX command an execution break point is set at
the location of the cursor position in the code
window. The cursor must be on a line that
contains code (place the code window in mixed
mode if you are unsure). The default function key
assignment for BPX is F9.
* Go to cursor line
You can set a temporary break point at the cursor
and go with the HERE command. The cursor must
be on a line that contains code (place the code
window in mixed mode if you are unsure). The
default function key assignment for HERE is F7.
134
* Scrolling the code window
The code window can be scrolled only while the
cursor is in the code window. The scrolling keys
(UP arrow, DOWN arrow, PageUp and
PageDown) are redefined while the cursor is in
code window. When the cursor is in the code
window the scrolling keys do the following:
up -- Scroll code window up one line
down -- Scroll code window down one
pageup -- Scroll code window up one window
pageDn -- Scroll code window down one
window
Note:
The code window must be visible for the EC command to work.
Default Function Key: F6
135
.
. -- Locate current instruction
Syntax:
.
Comments:
When the code window is visible, the . command makes the current source
line or current instruction visible.
136
5.8 Debugger Customization Commands
Commands:
PAUSE -- Pause after each screen
ALTKEY -- Set alternate key sequence to
invoke Soft-ICE
FKEY -- Show and edit function keys
BASE -- Set/display current radix
CTRL-P -- Toggle log session to printer
Print-Screen -- Print contents of screen
PRN -- Set printer output port
137
PAUSE
PAUSE -- Pause after each screen
Syntax:
PAUSE [ON | OFF]
Comments:
PAUSE controls screen pause at the end of each page. If PAUSE is ON, you
are prompted to press any key before information is scrolled off the
window. The prompt is displayed in the status line at the bottom of the
window.
If no parameter is specified, the current state of PAUSE is displayed.
The default is PAUSE mode ON.
Example:
PAUSE ON
This command specifies that subsequent window
display commands will cause the screen to wait for you
to press a key before scrolling new information off the
window.
138
ALTKEY
ALTKEY -- Set alternate key sequence to invoke Soft-ICE
Syntax:
ALTKEY [ALTletter] | [CTRLletter] | [SYSREQ]
letter - Any letter (A - Z)
Comments:
The ALTKEY command allows the key sequence for popping up Soft-ICE to be
changed. The key sequence be changed to CTRL + letter, ALT + letter, or
the SysRq key.
Occasionally you may be using a program that conflicts with the CTRL D key
sequence that brings up the Soft-ICE window. One way to circumvent this
possible problem is to use the ALTKEY command to change the key sequence.
Another way is to add the SHIFT key to the current sequence. Soft-ICE does
not respond to this key sequence and allows it to go through to your
program. For example if a resident program you are using is brought up
with the CTRL D key sequence, try using the key sequence CTRL SHIFT D to
bring up your resident program. On some keyboards, you must press ALT and
the prtsc key simultaneously to generate a system request. Care must be
taken so the screen is not printed accidentally.
If no parameter is specified, the current key sequence state is displayed.
The default key sequence is CTRL D.
139
Example:
ALTKEY ALT Z
This command specifies that the key sequence
ALT Z will now be used to pop up the Soft-ICE
window.
140
FKEY
FKEY -- Show and edit function keys
Syntax:
FKEY [function-key-name string]
function-key-name -- F1, F2... F12
string -- The string consists of any valid Soft-ICE
commands and the special character
^ (caret) and ; (semicolon). A ^ is
placed in the string to make a
command invisible. A ; is placed in
the string to denote a carriage return.
Comments:
The FKEY command is used from the command line to assign a function key to
a command string. Function key can be assigned to any command string that
can be typed into Soft-ICE.
If no parameters are specified, then the current function key assignments
are displayed.
To unassign a specified function key, use the FKEY command with these
parameters: a function-key-name followed by a null string.
The function keys can also be pre-initialized in the definition file S-
ICE.DAT. For more information on function key definitions in the
definition file, refer to section 6.4.
Using carriage return symbols in a function key assignment string allows
you to assign a function key a series of commands. A carriage return is
represented by a ; (semicolon).
141
If you put ^ (shift 6) in front of a function key definition, the
subsequent command will be invisible. The command will function as normal,
but all information displayed in the command window (including error
messages) is suppressed. The invisible mode is useful when a command
changes information in a window (code, register or data) but you do not
want to clutter the command window,
When a function key is made invisible with ^, the function key can be used
in the middle of typing in other command without affecting their
operation. For example, if you are using the default assignment for F2,
you can toggle the register window with F2 even if you are partially
through typing in your next command.
Note :
Soft-ICE now has a definition file named S-ICE.DAT. You can place function
key assignments in this file so that function keys will be automatically
assigned when Soft-ICE is loaded. The syntax for assigning a function key
in the configuration file is:
function-key-name = "string"
When assigning function keys to a command string in S-ICE.DAT, the string
must be enclosed in double quotes.
Command line examples:
FKEY F2 ^WR;
This example will assign the toggle register window
command to the F2 key. The ^ makes the function
invisible, and the ; ends the function with a carriage
return. The F2 key will toggle the register window
on or off, and can even be evoked while typing in
another command.
142
FKEY F1 "G CS:120; R; G CS:"
This example shows that multiple commands can be
assigned to a single function key and that partial
commands can be assigned for the user to complete.
After this command is entered, pressing the F1 key
will cause the program to execute until location
CS:120 is reached, display the registers, then start the
G command for the user to complete.
FKEY F1 WD 3;D DS:100;
This example will assign a series of commands to the
F1 key. The function is visible, and ends with a
carriage return. The F1 key will make the data
window three lines long and dump data starting at
DS:100.
S-ICE.DAT example:
F1 = "WR;WD 2;WC 10;"
If this line is placed in S-ICE.DAT, when Soft-ICE is
loaded it will assign the string to the F1 key. When
F1 is pressed while in Soft-ICE, it will toggle the
register window, create a data window of length 2 and a
code window of length 10. For more information about
assigning function key definitions in S-ICE.DAT, refer
to chapter 6.
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BASE
BASE -- Set/display current radix
Syntax:
BASE [10 | 16]
Comments:
The BASE command sets the current radix to base 10 or base 16. Base 10 is
of limited use in the narrow window because of window width limitations.
It also limits the amount of information displayed in some commands in the
wide mode.
When the current radix is base 10, all numbers and addresses typed into
and displayed by Soft-ICE are in decimal, When the current radix is base
16, all numbers and addresses typed into Soft-ICE are in hexadecimal
except:
* source line numbers
* screen coordinates and sizes in the WIN command
These exceptions are always typed in and displayed as decimal numbers.
The default radix is base 16.
Example:
BASE 16
This example sets the current radix to base 16.
144
CTRL-P
CTRL-P --- Toggle log session to printer
Syntax:
CTRL-P
Comments:
When the CTRL key followed by the P key is pressed, all subsequent
information displayed in the command window is also sent to the printer.
To turn the log to printer mode off, type CTRL followed by P again.
When you are sending a lot of information to the printer using CTRL-P, you
may want to turn the PAUSE command OFF to allow information to scroll off
the window without pressing a key.
145
Print-Screen
Print-Screen - Print contents of screen
Syntax:
Print-Screen
Comments:
Depressing the print-screen key does a screen dump to printer. All
information from the screen is sent the printer.
If you wish to print the memory map or help information is usually much
faster to use CTRL-P than Print-Screen. This is because Print-Screen
prints every character on the screen including borders.
146
PRN
PRN --- Set printer output port
Syntax:
PRN [LPTx | COMx]
x -- a decimal number between 1 and 4.
Comments:
The PRN command allows you to send output from the CTRL-P and Print-Screen
commands to a different printer port.
If no parameters are supplied, PRN displays the currently assigned printer
port.
Example:
PRN COM 1
This command causes the CTRL-P and Print-Screen
command output to go to the COM 1 port.
147
5.9 Screen Control Commands
Commands:
FLASH -- Restore screen during P and T
FLICK -- Screen flicker reduction
WATCHV -- Set watch video mode
RS -- Restore program screen
CLS -- Clear window
ALTSCR -- Change to alternate screen
WIN -- Change size of Soft-ICE window
148
FLASH
FLASH -- Restore screen during P and T
Syntax:
FLASH [ON | OFF]
Comments:
The FLASH command lets you specify whether the screen will be restored
during any Trace and Program step commands. If you specify that the screen
is to be restored it is restored for the brief time period that the P or T
command is executing. This feature is needed to debug sections of code
that access video memory.
If the P command executes across a call or an interrupt, the screen will
always be restored, because the routine being called may write to the
screen.
If no parameter is specified, the current state of FLASH is displayed.
The default is FLASH mode OFF.
Example:
FLASH ON
This command turns on FLASH mode. The screen will
be restored during any subsequent P or T commands.
149
FLICK
FLICK -- Screen flicker reduction
Syntax:
FLICK [ON | OFF]
Comments:
Certain types of video cards require waiting for horizontal or vertical
retrace before outputting characters. If the video writes are made
arbitrarily, flickering will appear while displaying characters. If
flickering occurs on your screen while using the Soft-ICE window, you
should turn FLICK on.
With some EGA cards, colors will not be restored properly when you exit
from Soft-ICE. This is a problem with virtualizing EGA video. The port 3DA
is a video port used for two purposes. The first is old CGA software
polling 3DA for hsync and vsync. This allows them to have flicker free
output on some old CGA controller cards. The second is that it is used to
reset a palette latch on EGA cards. Soft-ICE has an algorithm to avoid
having to constantly watch this port, which would slow down old programs
that think they are on a CGA. However, there can occasional be
circumstances where this algorithm does not work. If you are using Soft-
ICE on an EGA screen and you notice that the colors are not restored
correctly, then turn FLICK ON and Soft-ICE will watch the 3DA port, fixing
the problem.
When FLICK mode is ON, screen update will be slower.
If no parameter is specified, the current state of FLICK is displayed.
The default is FLICK mode OFF.
150
Example:
FLICK ON
This command turns on FLICK mode. This causes
Soft-ICE to wait for the horizontal or vertical retrace
before outputting characters.
151
WATCHV
WATCHV -- Set watch video mode
Syntax:
WATCHV [ON | OFF]
Comments:
The WATCHV command allows you to specify how Soft-ICE should watch the
video ports. Normally, Soft-ICE only watches video ports after an INT 10
instruction has been executed that switches to a non-character video mode.
Some programs do not use INT 10 to switch modes. In these cases, if WATCHV
is OFF, Soft-ICE may have trouble saving and restoring the screen
properly. Turning WATCHV ON will cause Soft-ICE to watch the video ports
all the time.
Turn WATCHV ON if you notice that Soft-ICE is not handling your screen
properly, or if the cursor is not being restored properly. Turning WATCHV
ON may have a performance impact in certain video modes.
If no parameter is specified, the current state of WATCHV is displayed.
The default is WATCHV mode OFF.
Example:
WATCHV ON
This command turns on WATCHV mode. This causes
Soft-ICE to watch additional video ports for the
purpose of virtualization.
152
RS
RS -- Restore program screen
Syntax:
RS
Comments:
The RS command allows you to restore the program screen temporarily. The
Soft-ICE window disappears until any key is pressed.
This feature is useful when debugging graphic programs that update the
screen frequently. When Soft-ICE is brought up, it returns to text mode.
Using the RS command temporarily restores the graphics screen.
Example:
RS
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CLS
CLS -- Clear window
Syntax:
CLS
Comments:
The CLS command clears the Soft-ICE window and moves the prompt and the
cursor to the upper left-hand corner the window.
Example:
CLS
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ALTSCR
ALTSCR -- Change to alternate screen
Syntax:
ALTSCR [ON | OFF]
Comments:
The ALTSCR command allows you to redirect the Soft-ICE output from your
default screen to the alternate screen. This feature is useful, for
instance, when you want to debug a graphics program without having to
switch between the Soft-ICE window and the graphics display.
ALTSCR requires the system to have two monitors attached. The alternate
monitor should be in a character mode, which is the default mode for
monitors.
The default is ALTSCR mode OFF.
Example:
ALTSCR ON
This command redirects screen output to the alternate
monitor.
155
WIN
WIN -- Change size of Soft-ICE window
Syntax:
WIN [N | W] [start-row length [start-column]]
N -- When N is specified, the window will
be set to the narrow width: 46
characters.
W -- When W is specified, the window will
be set to full screen width.
start-row -- Number from 0 to 17 specifying row
where window display starts.
length -- Number from 8 to 25 specifying how
many lines tall you want the window
to be.
start-column-- Column position of the left side of
narrow window. The start-row and
start-column specify the upper left
hand corner of the narrow window.
The start-column is ignored if applied
to the wide window.
Comments:
The WIN command allows you to modify the width and height of the Soft-ICE
display window.
If no parameters are specified, this command toggles the window between
wide and narrow screen display modes.
If the WIN command is specified with only the N or the W parameter, the
window size will be changed to the requested width at the current height.
156
If the number of lines plus the starting row number is larger than 25, the
window length goes to the bottom of the screen.
The default is WIN mode narrow.
Examples:
WIN N 4 9 30
This command causes the window display to start at
row 4 and column 30, and to be 9 rows tall and 46
characters wide.
WIN
This command toggles the window display width from
its current state (either wide or narrow) to the opposite
state.
WIN W 10 8
This command causes the window display to start at
row 10, and to be 8 rows tall and go the width of the
screen.
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5.10 Symbol and Source Line Commands
Commands:
SYM -- Display/set symbol
SYMLOC -- Relocate symbol base
SRC -- Toggle between source, mixed and code
FILE -- Change/display current source
SS -- Search current source file for string
158
SYM
SYM -- Display/set symbol
Syntax:
SYM [symbol-name [value]]
symbol-name -- A valid symbol name. The symbol
name can end with an * (asterisk).
This allows searching if only the first
part of the symbol name is known.
The , (comma) character can be used
as a wild card character in place of
character in the symbol-name.
value -- This is a word value that is used if you
want to set a symbol to a specific value.
Comments:
The SYM command allows displaying and setting of symbols. If SYM is
entered with no parameters all symbols are displayed. The value of each
symbol is displayed next to the symbol name.
If a symbol name is specified with no value then the symbol name and value
are displayed. If the symbol name was not found then nothing is displayed.
The SYM command is often useful for finding a symbol name when you can
only remember a portion of the name Two wild card methods are available
for locating symbols. If symbol-name ends with an *, then all symbols that
match the actual characters typed prior to the * will be displayed
regardless of their ending characters. If a , is used in place of a
specific character in symbol-name, that character is a wild card
character.
If value is specified, all symbols that match symbol-name are set to the
value. All symbols have word values.
159
Examples:
SYM FOO*
All symbols that start with FOO are displayed.
SYM FOO* 6000
All symbols that start with FOO are given the value
6000.
160
SYMLOC
SYMLOC -- Relocate symbol base
Syntax:
SYMLOC segment-address
Comments:
The SYMLOC command relocates the segment components of all symbols
relative to the specified segment address. This function is necessary when
debugging loadable device drivers or other programs that can not be loaded
directly with LDR.EXE.
When relocating for a loadable device driver, use the value of the base
address of the driver as found in the MAP command. When relocating for an
.EXE program, the value is 10H greater than that found as the base in the
MAP command. When relocating for a .COM program, use the base segment
address that is found in the MAP command.
The MAP command will display at least two entries for each program. The
first is typically the environment and the second is typically the
program. The base address of the program is the relocation value.
Example:
SYMLOC 1244 + 10
This will relocate all segments in the symbol table
relative to 1244. The + 10 is used to relocate a TSR
that was originally a .EXE file. If it is a .COM file the
+ 10 is not necessary.
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SRC
SRC -- Toggle between source, mixed and code
Syntax:
SRC [?]
Comments:
The SRC command toggles between source mode, mixed mode and code mode in
the code window.
If SRC ? is entered, the current state is displayed.
Example:
SRC
This command changes the current mode of the code
window. If the mode was source, it becomes mixed.
the mode was mixed, it becomes code. If the mode was
code, it becomes source.
Default-Function Key: F3
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FILE
FILE -- Change/display current source file
Syntax:
FILE {file-name]
Comments:
If a file-name is specified, that file becomes the current file and the
start of the file is displayed in the code window. If no name is
specified, the name of the current source file (if any) is displayed.
The FILE command is often useful when setting a break point on a line that
has no associated public symbol. Use file to bring the desired file into
the code window, use the SS command to locate the specific line, move the
cursor the specific line, then type BPX to set the break point.
Note:
Only source files that have been loaded into extended memory with LDR.EXE
are available with the FILE command.
Example:
FILE MAIN.C
If MAIN.C had been loaded with LDR.EXE, this
command brings it up in the code window starting with
line 1.
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SS
SS -- Search current source file for string
Syntax:
SS [line-number] [' string']
line-number -- a decimal number
string -- a character string surrounded by quotes
The quotes can be either single quotes
or double quotes.
Comments:
The SS command searches the current source file for the specified
character string. If there is a match, the line that the string was
located in will be displayed as the top line in the code window.
The search starts at the specified line number. If no line number is
specified the search starts at the top line displayed in the code window.
If no parameters are specified, the search continues for the previously
specified string.
Note:
The code window must be visible and in source mode before using the SS
command.
Example:
SS 1 'if (i = = 3)'
The current source file is searched starting at line 1 for
the string 'if (i = = 3)'. The line containing the next
occurrence of the string becomes the top line displayed
in the code window.
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