ORG : Origin:-
The ORG directive directs the assembler to begin the memory allotment for the specific segment, code or block from the declared address in the ORG statement. Whereasstarting the assembly process for a module, the assembler initialises a location counter to keep track of the allotted addresses for the module. If the ORG statement is not written in program, the location counter is initialised to 0000. If an ORG 200H statement is there at the beginning of the code segment of that module, then the code will begin from 200H address in code segment. In other term, the location counter willinitialise to the address 0200H instead of 0000H. Therefore, the code for different segments andmodules may be located in the available memory as required by the programmer. The ORG directive can even be utilized with data segments in similar way.
The PROG directive marks the start of a named process in the statement. The types NEAR or FAR mention the type of the procedure, for example. Whether it is to be called by the main program located within 64K of physical memory or not. For instance, the statement RESULT PROC NEAR marks the start of a routine RESULT that is to be called by a program located in the similar segment of memory. The FAR directive which is used for the procedures to be called by the programs located in different segments of memory. The example statements are following:
RESULT PROC NEAR ROUTINE PROC FAR