Using HCON Overview

The 3270 Host Connection Program (HCON) emulates a 3278/79 display or a 3286/87 printer attached to a System/370 mainframe host. This chapter involves working with the following:

• S/390 host double-byte character set emulation
• HCON sessions and session profiles
• The 3270 emulator
• The HCON utility program
• Customizing HCON color and highlight values
• HCON File transfers
• HCON host logon procedures

HCON operates in sessions, periods of interaction with a host computer. A printer session emulates a 3286/87 printer. A display session emulates a 3278/79 terminal display. A printer session prints files from the host computer on a local printer or stores printable files on the local system. At the beginning of a display session, the emulator acts as if you had just started the 3278/79 terminal. After logging on to the mainframe host, you can:

• Run commands or start applications running on the S/390.
• Run programs that communicate with the mainframe host using High-Level Language Application Programming Interface (HLLAPI).

  Note: This interface is compatible with the (3270 PC) HLLAPI Version 3.00. For more information, see the "High-Level Language Application Programming Interface".

• Use the fxfer command to upload and download files to and from the host.

HCON is only accessible to registered users. Registration requires root authority and involves entering a user login ID. Once registered, you or a user with root authority must create at least one session profile before running HCON. The session profile specifies the following parameters for emulator sessions:

• Type of host
• Type of emulation, display, or printer
• Type of connection with the host
• Type of protocol with the host, such as TCP/IP, SNA, or DFT

A session profile enables a connection session from the workstation to a S/390 host, using similar or differing parameters. Session characteristics are defined in the session profile. Each session requires a predefined session profile. This includes characteristics such as:

• Language or code page
• Color and keyboard definition tables
• Host field and character attributes
• Terminal key locations and key sequence
• Session profile tables
• Display screen size
• Miscellaneous session-related information

The HCON High-Level Language Application Programming Interface (HLLAPI) allows communication with a mainframe host in different environments. Applications can be created to simulate an interface requiring no user intervention for program-to-program communication and data translation.