An Input Data-Entry Field, is an Area - where the User is expected to type some data-value and supply Input. The Data in this field is keyed-in by the User. Hence, the User is free to type any Input he desires in these fields. Data-Entry Fields are therefore, said to be un-protected(UNPROT).
When you run COBOL-Programs in Batch-Mode, by writing a Job, the Input-Data to these Programs is generally stored in Mainframe-Files(Datasets). What about COBOL Programs run in Online-Interactive Mode ; have you wondered, what’s their source of the Input-Data? Bingo! Data-Entry Fields are the Primary-Source of Feeding Input-Data to the COBOL-Programs run in Online Mode under CICS. It should clear, that COBOL-Programs run in Online-Mode under CICS, read the Data from Input Data-entry Fields, process the Data, and generate Output.
Since COBOL Programs need to access and read the Data from Input-Fields, it is important that you assign a name or Label to your Input-Fields on the CICS Screen. The Input-Screen INPMAP has Input-Fields containing two empty Blanks '__' adjacent to 'FIRST NUMBER : ' and 'SECOND NUMBER : ' Display-Fields. I have named them NUMBER1 and NUMBER2.
How to calculate the Position or Placement of Consecutive-Fields? You employ a simple formula (start + Length + 1 ). For example, 'FIRST NUMBER : '
display-only field starts at column 3, and is 15 bytes long. So, the '__' Input-Field next to it can start on or after (03 + 15 + 1) = Column 19. You shouldn’t be surprised, as to why I've positioned NUMBER1 and NUMBER2 Fields at (5,19) and (7,19) respectively.