Dave's TN3270 FAQ page

"Drive like the wind, straining the limits of machine and man."
Rush - Red Barchetta

Use this information at your own risk. Take backups of any config files you change BEFORE you change them.

What VTAM logmode should I use for a non-standard screen size?

D4C32XX3 - This is an IBM supplied LOGMODE and should be in your VTAMLIB

Here are some sample commands to use at the TCPIP USS screen after changing your TN3270 emulator to use non-standard screen sizes:

logon applid(tso) logmode(d4c32xx3)
logon applid=tso logmode=d4c32xx3

Or you may prefer to make D4C32XX3 the default logmode because it works with everything. Do this by specifying D4C32XX3 in your TCPIP stack profile in the BEGINVTAM section:

BEGINVTAM
TELNETDEVICE 3277 D4C32XX3
TELNETDEVICE 3278-2-E D4C32XX3,D4C32XX3
TELNETDEVICE 3278-2 D4C32XX3,D4C32XX3
TELNETDEVICE 3279-2-E D4C32XX3
TELNETDEVICE 3279-2 D4C32XX3
TELNETDEVICE 3278-3-E D4C32XX3,D4C32XX3
TELNETDEVICE 3278-3 D4C32XX3,D4C32XX3
TELNETDEVICE 3279-3-E D4C32XX3
TELNETDEVICE 3279-3 D4C32XX3
TELNETDEVICE 3278-4-E D4C32XX3,D4C32XX3
TELNETDEVICE 3278-4 D4C32XX3,D4C32XX3
TELNETDEVICE 3279-4-E D4C32XX3
TELNETDEVICE 3279-4 D4C32XX3
TELNETDEVICE 3278-5-E D4C32XX3,D4C32XX3
TELNETDEVICE 3278-5 D4C32XX3,D4C32XX3
TELNETDEVICE 3279-5-E D4C32XX3
TELNETDEVICE 3279-5 D4C32XX3
TELNETDEVICE DYNAMIC ,D4C32XX3
TELNETDEVICE 3287-1 ,D4C32XX3

Note: you can change this dynamically by using a TCPIP obey file. This obey file should have both TELNETPARMS-ENDTELNETPARMS and BEGINVTAM-ENDVTAM definitions. You must have both even if not changing the TELNETPARMS. I would recommend using the OBEY file method on this and other TCPIP changes so you can find syntax and other problems dynamically and not have TCPIP fail to initialize at IPL time. I'd also recommend doing the OBEY command on weekends or after hours when changing the production TCPIP stack.

Is the D4C32XX3 logmode good only for non-standard screen sizes?

There is a lot more to be gained from the use of D4C32XX3 than just "non-standard" screen dimensions. This logmode indicates that a read partition query is to be issued by host applications to determine the capabilities of the device. Yes, the information returned contains the dimensions of the presentation space. But it also indicates whether extended highlighting, extended color, programmed symbols, vector graphics, graphics escape characters, and other facilities are supported by the emulator. By continuing to use the default NSx3270x logmodes for terminals with "standard" screen dimensions, you ensure all of the other extended capabilities are also disallowed.
- Contributed by Ed Jaffe

What is meant by non-standard screen size?

These are screen sizes that differ from the actual hardware 3270 terminal devices that IBM (and others) use to sell:

Name	Rows	Columns
3278-2	24	80
3278-3	32	80
3278-4	43	80
3278-5	27	132

You may hear slang like: "I'm using a mod 2 terminal". That means a 24x80 screen.

What software works in the non-standard screen size?

ISPF supports non-standard screen sizes. It depends on the ISPF application whether the full advantage of addtional rows and columns are used. Many ISPF applications that use ISPF services like tables will use all of the rows available. While other ISPF applications like SDSF use dynamic areas and use all available rows and columns. ISPF file browse, edit and view also take advantage of additional rows and columns depending on the data.

You should review your settings on ISPF option 0:

Terminal Characteristics
Screen format 3 1. Data 2. Std 3. Max 4. Part

Option 3 for Max uses the full screen all of the time. Some like Option 2 for Data where the screen changes from 24x80 to the alternate screen size based on the data. The FAQ author prefers the Max option.

Some non-ISPF applications like the REVIEW command (file 134/135 on www.cbttape.org) also takes advantage of larger screen sizes. The REVIEW command requires columns to be an even number like 132 instead of 133.

How do I get a non-standard screen size with IBM's PCOMM TN3270 emulator?

Update the session.ws file for the session using a text editor to get the desired screen size. It is in the [3270] section:

[3270]
ScreenSize=62x132

Use your system's file finder to locate the session.ws file. On my system, they reside in C:\Program Files\IBM\Personal Communications\private because of the way I installed PCOMM.

Tested successfully using PCOMM version 5.5.

Here is a WSC flash on Creating dynamic 3270 screen size definitions for increased productivity (local mirror)

How do I get a non-standard screen size with the QWS3270 emulator?

Upgrade to QWS3270 version 3.8 or higher. The alternate screen size can be specified in the options for IBM-DYNAMIC terminal type. Tested with normal screen size of 24 rows and 80 columns with alternate screen size of 43 rows and 132 columns.

Tested successfully using QWS3270 version 3.8.

How do I fix the annoying hangup that occurs at the VTAM USS screen of IBM's ADCD (developer) system when using IBM's PCOMM emulator?

Add the following [LT] section to the session.ws file for the session.

[LT]                    
IgnoreWCCStartPrint=Y   
UndefinedCode=Y         
UndefinedDBCSChar=Y

Do you have a sample EHLLAPI Rexx exec?

Starting from advice and code from this Using EHLLAPI in REXX article, startup.txt will automate the start of a PCOMM session and logon to TSO. This exec will need to be modified for your logon process.

There is EHLLAPI programming information in this PDF file PCOMM Emulator Programming (slow load). The sample EHLLAPI programs mentioned in this manual were NOT found on the PCOMM 5.5 CDROM. file:///Volumes/Bay2Web/planetmvs.com/mvsintosh/index.html

Tested successfully using PCOMM version 5.5. Other emulators like Attachmate, Rumba, Simware, etc. provide EHLLAPI support and may work as well.

Does the inclusion of only PCOMM and QWS3270 entries in your FAQ imply some type of endorsement of these products?

No. I am at the mercy of my current and previous employers and my experience is limited to those I've used on work supplied PC and software.

How can I tell ISPF to display drawing characters? [2008-07-10]

Note: This is not a TN3270-only issue

Using the default ISPF terminal types of 3277 or 3278 results in some drawing characters being displayed as garbage. For example if you browse SYS1.MODGEN(ASAXWC) at about line 99 (at z/OS 1.9 level):

You can fix this by using the SETTINGS command on the command line (or option 0 on the main menu) to change the terminal type from 1 (3277) to 6 (3278T) and then the syntax drawing characters display as intented:

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