Wednesday, December 12, 2007

z390 Mainframe Assembler Coding Contest

Checkout the new z390 mainframe assembler coding problems and submitted solutions here:

You can join the growing group of participants and submit as many problems and solutions as your like.

Don Higgins

Thursday, October 25, 2007

z390 source and downloads now on

The open source z390 Portable Mainframe Assembler and Emulator source and release downloads are now available from mirrorded z390 project site at

The source is now in CVS form and can be browsed via the web here:

Don Higgins

Friday, October 05, 2007

VSAM and CICS compatible support in z390 v1.3.08

This week z390 v1.3.08 was published for download and install via InstallShield for Windows Vista and XP along with file image for Linux installs. This version has new VSAM support including ESDS, RRDS, VRRDS, and KSDS support for random and skip sequential access by primary key. Also in this release of z390 is V3 of CICS compatible support developed by Melvyn Maltz including new BED9 test transaction to create ESDS file and then CEBR transaction to browse the file forward and backword via PF7 and PF8 keys and toggle record formates between EBCDIC, ASCII, and hex using PF2 key.

All the documentation has updated with links from Demo and regression tests are also included.

Don Higgins

Saturday, August 25, 2007

z390 SHARE Session Update

z390 SHARE sessions have been held at the February and August 2007 conferences. Martin Trubner from Germany presented the last session in San Diego providing z390 user perspective. For more information visit:

Planning is now underway for z390 SHARE session in Orlando in February 2008 with both Don Higgins and Melvyn Maltz presenting updates on z390 support for VSAM and CICS. Plan to attend.

Don Higgins

z390 new VSAM assembler application support

Starting with version 1.3.07, z390 now supports VSAM assembler applications. The initial support includes ESDS files using macros for ACB, RPL, OPEN, CLOSE, GET, PUT, SHOWCB, TESTCB, and MODCB. A new utility REPRO written in structured macro assembler is included to load or unload VSAM file from/to QSAM file or another VSAM file. Fixed or variable length records up to 2 GB are supported. Demo application programs with fixed and variable length ESDS VSAM files are included. For more information visit:

Don Higgins

z390 new CICS compatible transaction manager

z390 version 1.3.05 now has a CICS compatible transaction manager V2 developed by Melvyn Maltz which supports EXEC CICS assembler programs. Commands supported include EXEC SEND, RECEIVE, LOAD, LINK, XCTL, RETURN, HANDLE, ABEND, PUSH, POP, RELEASE, GETMAIN, and FREEMAIN. A z390 CICS transaction manager server can support multiple local and remote TN3270 compatible clients connected over TCP/IP network. All of the code is open source. To start a server run z390\cics\z390cics.390 and to start a client run z390\cics\z390kcp with IP address of the server processor. To see an example, enter the transaction code GUI6 to start a conversational CICS transaction which displays several fields (name, address, zip) and supports updating fields plus PF1 help key and PF3 exit key. For more information visit:

Don Higgins

Tuesday, June 12, 2007

How to speed up Java emulator by 50%

z390 release v1.3.04 includes simple change to the source to speed up the emulator
by 50% with new BCT loop speed of 1.6 MIPS on a 2.1 GHZ Intel dual core processor. The only change made was to split the primary and seconardary operation code switches into separate functions which results in smaller working set for the generated Java byte code. On cached pipeline processors this can dramatically improve performance.

Don Higgins

EXEC CICS compatible tranaction manager in z390 v1.3.04

The latest z390 version v1.3.04 has new EXEC CICS compatible transaction manager contributed in open source z390 assembler contributed by Melvyn Maltz. This new tool supports multiple clients connected to server on a TCP/IP network. The initial release includes support for EXEC CICS SEND, RECEIVE, LOAD, LINK, XCTL, and RETURN commands and uses z390 GUAM TN3270 support for clients. Documentation and examples are included in the release stored in cics directory.

Don Higgins

Wednesday, April 18, 2007

z390 SUPERZAP utility available in v1.3.03

A new version of the old SUPERZAP file utility is available in z390 v1.3.03. This utility is distributed as open source as part of z390 and consists of about 850 lines of structured mainframe macro assembler. The utility supports the verification, replacement, and dumping of file contents in hex, ASCII, or EBCDIC. Files up to 2 GB on Windows or Linux are supported. Addition commands are supported to search for hex or text values and a loop command allows repeating search, verify, replace, and/or dump commands until verify fails or end of file is reached. For more information on this utility visit

This utility illustrates the power of structured mainframe assembler for use in utilities and applications running on not only on mainframes but also Windows and Linux platforms. SUPERZAP uses new extension in z390 v1.3.03 to set DCB record lengths up to 31 bits thus allowing utility to read or write an entire file up to 2 GB with a single GET or PUT.

SUPERZAP has been around as a mainframe utility from at least the early S/360 days for applying Private Temporary Fixes (PTF's) to operating system code. Today it is called SPZAP or AMASPZAP and is documented in the DFSMS Diagnosis Tools manual. See reference links on the page.

Don Higgins

Tuesday, March 13, 2007

z390 now supports VSE assembler programs

With the release of z390 v1.3.02b PTF there is a new VSE macro library which maps VSE assembler macros into z390 MVS compatible macro code which can be assembled, linked, and executed on Windows, Linux, or any platform supporting z390 running on J2RE 1.5.0+.

Several demos and regression tests are include to illustrate the use of VSE marcros such as COMRG, GETTIME, CDLOAD, CDDELETE, GETVIS, FREEVIS, OPEN, DTFSD, DTFPR, GET, PUT, CLOSE, and EOF.

Don Higgins

Saturday, February 17, 2007

SHARE Session 2845 z390 Portable Mainframe Assembler and Emulator

SHARE was held in Tampa Florida during the past week, and I had the opportunity to present a session on the z390 Portable Mainframe Assembler and Emulator. One question from the session was whether z390 could be run on z Series machines using Linux/390. To date z390 has only been fully tested on Windows and Ubuntu Linux 6.06 LTS and J2RE 1.5.0_10. However since Ubuntu Linux and Linux/390 both conform to the new Linux Foundation core standard and since both support the J2RE 1.5 Java code base from Sun Microsystems, I see no reason why z390 should not run on Linux/390. Although it would be slower than native assembler of course, if the process is I/O bound, then speed may not be an issue. The potential benefit is to have assembler application code that is portable across both OS's and hardward platforms.

I attended several other sessions at the SHARE in Tampa and perhaps the most interesting for me was the session on Linux and Open Source by Jim Elliott with IBM Canada. He presented the results of a recent Gartner survey showing server growth statistics for different OS's. Linux growth was up 31%, Windows server growth was up 12%, Unix server growth was up 4% and all other servers were in decline by 22%. It seems to me that there is a clear message here about the future of Linux and other open source tools such as Java, Eclipse, and z390.

Thursday, January 11, 2007

z390 Service Oriented Architecture Support

With z390 PTF v1.2.00g new Service Oriented Architecture (SOA) support has been added. A new macro TCPIO and svc x'7c' now support TCP/IP sockets messaging. In addition a new SOA client server application generator macro facility has been added along with a demo application. The demo consists of a main proram and two called subroutines. As a base line, the demo can be assembled, statically linked, and executed. Then the SOAGEN macro facility can be used to generate client and server message managers plus stubs for each called serivce. See the new z390 Service Oriented Architecture User Guide here:

Don Higgins