Category : Assembly Language Source Code
Archive   : ASMTUT1.ZIP
Filename : TASM.DOC

 
Output of file : TASM.DOC contained in archive : ASMTUT1.ZIP




1

USING TASM


This is absolutely the easiest chapter in the book. The default
mode for TASM is something called MASM mode. It imitates what
MASM does, warts and all. When you are finished with the Tutor,
you can decide whether you want to use "IDEAL" mode.

The following are the minor differences from MASM.


===== CHAPTER 1

To assemble the file myprog.asm use:

>tasm myprog

You don't need commas or semicolons or anything. Then if you are
using TLINK, use:

>tlink myprog+\asmhelp

The batch file for this would be:

>tlink %1+\asmhelp

No commas or semicolons.


===== CHAPTER 10

To get your list file put three commas after the filename:


.tasm myprog, , ,

This will produce MYPROG.LST. You will notice that the list
files look similar.

Page 94 - This is the TURBO listing for variable2:

42 000E 8E C0 mov es,ax
43
44 0010 26: 8B 0E 0000r mov cx, variable2
45 0015 26: 89 0E 0000r mov variable2, cx
46
47 001A CB ret


This is the TURBO listing for variable3:

42 000E 8E C0 mov es,ax
43
44 0010 2E: 8B 0E 0000r mov cx, variable3
45 0015 2E: 89 0E 0000r mov variable3, cx
46
47 001A CB ret
48





The PC Assembler Tutor 2
______________________


This is the TURBO listing for variable4:

42 000E 8E C0 mov es,ax
43
44 0010 36: 8B 0E 0000r mov cx, variable4
45 0015 36: 89 0E 0000r mov variable4, cx
46
47 001A CB ret
48


Except for the line numbers at the left, they look exactly the
same as what is in the text. TASM is calculating the segment
overrides.


PAGE 99 - This is the TURBO listing for calls similar to the ones
on page 99:

89 0AFF E8 FEC8 call near_routine
90 0B02 9A 00000AF6sr call far_routine
91 0B07 E8 0000e call near_external_routine
92 0B0A 9A 00000000se call far_external_routine
93 0B0F E8 0000e call get_unsigned

and here is the MASM output for the same file:

0AFF E8 09CA R call near_routine
0B02 9A 0AF6 ---- R call far_routine
0B07 E8 0000 E call near_external_routine
0B0A 9A 0000 ---- E call far_external_routine
0B0F E8 0000 E call get_unsigned

Why is that first number different (FEC8 vs. 09CA)? Turbo knows
the correct value so it is inserting it into the code. MASM is
passing the information on to the linker for calculation. The
first way makes the linking faster.

Some of these numbers are reversed for display purposes. The
actual code is the same.


===== CHAPTER 21

You don't need to use EXE2BIN after TLINK. TLINK will make a .COM
file (if possible) from object files if you use the /t option
with the following commands:

>tlink /t myprog
>tlink /t prog1+prog2+prog3

you will get .COM files as output.