			      HELP FILE FOR RASM
		     ----------------------------------------

Here are a few guidelines one must follow while using NASM:

1) The source file should have an extension  .PDP

2) A .ORG statement can be used to specify the exact memory location from
    where the object code is to be placed. In the absence of such a statement
    the initial location is taken to be 000000(octal).

3) The assembly language is case - insensitive and hence care should be
    taken while defining symbols or macro names.

4) Labels and symbols cannot exceed 12 characters. This field is to be
     terminated by a ':'.

5) The only pseudo-op's defined are .ORG, .BLKW ,.DB,.DW ,.EQU  and .END .
     A pseudo-op has to begin with a '.'(period). Any program has to
     terminate with a .END statement.
Note: HALT INSTRUCTION TO BE USED AS THE LAST INSTRUCTION IN MAIN PROGRAM.

6) Operands are to be separated by a ','(comma).

7) Comments are preceded by a ';' on each line.

8) Only 1 assembly language statement is allowed on a line.

9) Any numeric literal is to be followed immediately by its base.
     ( O for octal, D for decimal, H for hexadecimal and B for binary).
     No default base has been provided for in the design.

10) A macro definition has to be preceded by a .MACRO statement followed by
    the name of the macro and the parameter list enclosed within paranthesis
    and separated by ','. Each of these parameters are to be preceded by a
    '&' symbol. The end of a macro definition is specified by the .MEND
    statement.
eg.    .MACRO
       macro_name (&arg1,&arg2...)
		..
		.. (body of macro)
		..
	  .MEND

11) The name of the macro cannot exceed 10 characters.

12) A macro has to be defined before it is called for expansion. This is
    because macro definition and expansion takes place in a single pass.

13) No macro definitions within a macro defintion is allowed.

14) A macro call is recognized by the name of the macro followed by a space
    and arguments separated by ','.
eg.  macro_name  arg1,arg2....

15) A maximum of 10 parameters are allowed in a macro definition.

16) Finally if there are no syntax errors in the source program the object
     code is listed in a file which has the same name as the source file
     but with an extension .OUT. The listings will be of the form
     ADDRESS  INSTRUCTION/DATA with the values displayed in octal form.