Some More Frequently Asked (and Answered) Questions

1. Why don't I see any output on my telnet or 3270 client?
2. Why doesn't Hercules IPL my mainframe OS
3. I have set ARCHMODE correctly, and still Hercules doesn't IPL my OS. Why not?
4. Why can't I use more than 220 MB of mainsize on Hercules for Windows?

Why don't I see any output on my telnet or tn3270 screen?

The telnet clients usually use port 23 for their connection port. Hercules specifies the listening port in the Hercules configuration file with the CNSLPORT parameter. It is usually set to 3270. With other word, you must point your 3270 or telnet client to that port

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Why doesn't Hercules IPL my mainframe OS? I tried with MVS turnkey system, and it worked, but with xx/390 it doesn't.

You need to set the correct ARCHMODE in the Hercules configuration file. You can choose from

• S/370
• ESA/390
• ESAME

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I have set ARCHMODE correctly, and still Hercules doesn't IPL my OS. Why not?

The Operating system you are trying to IPL might be licenced by IBM. IBM does not normally allow running their licensed OS under Hercules. Therefore the capability of running those operating systems (like OS/390, z/OS, and others) has been switched off in Hercules beginning with Version 2.16. After you have obtained a valid license for running the OS on Hercules, you can switch support back on again using the

PGMPRDOS LICENSED

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Why can't I use more than xxx MB of main storage with Hercules on Windows?

There are two solutions to this problem. The first involves modifying the Windows registry. If you don't feel comfortably doing so, you might consider the second alternative

Hercules uses CYGWIN on the Windows platform. CYGWIN has a registry setting with which you can control the size of the memory that can be allocated to a CYGWIN application:

Stop hercules and all CYGWIN applications (like CYGWIN terminal sessions etc).

Use REGEDIT to locate the registry entry at

HKEY_CURRENT_USER\Software\Cygnus Solutions\Cygwin\

Create a new DWORD value there called heap_chunk_in_mb that contains the maximum amount of memory (in Mb) Hercules needs (watch the hex/decimal toggle). Exit and restart all cygwin applications.

Here is an alternative if you don't want to fiddle around with the registry. I haven't tried it, but take a look at http://sources.redhat.com/ml/cygwin/2000-08/msg00325.html

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