> In 1980 I bought my first Radio Shack TRS-80 personal computer with 64k > Z80 chip and CP/M operating system. I thought I had died and gone to > heaven having my own "mainframe" at home 24/7.
Ah, yes. The good old days. Zilog z80 was/is one of the best chips to work with. It's assembler was great. But I digress. Thanks for the memory. On Fri, Nov 4, 2011 at 6:00 AM, Don Higgins <d...@higgins.net> wrote: > All > > In addition to the recommendations already posted, you may find it useful > to download, install, and use the z390 Portable Mainframe Assembler and > Emulator from www.z390.org. This open source free tool comes with HLASM > compatible macro assembler and emulator for problem state instructions up > through z9, z10, and z196 mainframe processors. It comes with > InstallShield for Windows and also comes in file image format for > installation on Linux and Apple OSX systems. It's only pre-requisite is a > free version of J2SE Java 1.6+. It has lots of demo and regression test > programs plus a zCOBOL compiler and a zCICS transaction processor all > written in HLASM assembler for z390. > > There is a lot to learn about mainframe system programming. For a > starting point, I'd suggest installing z390 and studying the demo "Hello > World" program which uses WTO macro to generate code to issue console > message with the text "Hello World". The macro expands to generated an > SVC 35 supervisor call to request the display of message with the address > of the message block placed in register 1. This is perhaps the mostly > used SVC that has remained basically the same through OS, VS1, VS2, MVS, > and the z/OS mainframe operating systems and z390. You can assemble, > link, and execute the demo from the z390 GUI or command line prompt using > the command ASMLG demo\DEMO TRACE. This command does the following: > > 1. mz390 assembler reads DEMO.MLC source HLASM assembler demo program > 2. mz390 assembler generates DEMO.PRN assmebler listing > 3. mz390 assembler generates DEMO.OBJ relocatable object code file > 4. lz390 linker reads the DEMO.OBJ relocatable object code file > 5. lz390 linker generates DEMO.LST listing of CSECT map for load module > 6. lz390 linker generates DEMO.390 executable load module file > 7. ez390 emulator reads the DEMO.390 load module file > 8. ez390 emulator generates the DEMO.LOG console log file with WTO message > 9. ez390 emulator generates the DEMO.TRE execution instruction trace file > > All of the above files are standard ASCII files except the OBJ and 390 > binary code files. Once you have generated the above files on your > system, the next thing I would do is study the z390\demo\DEMO.MLC source > program file, the generated assembler listing file z390\demo\DEMO.PRN and > the associated called macro files in z390\mac directory using the HLASM > Language Reference Manual to answer questions. Then I would study the > execution trace file z390\demo\DEMO.TRE using the Principles of Operations > Manual to look up each instruction and study the before and after register > values and instruction address etc. Since the instructions used in this > demo program as used in almost every program you will ever write, they are > worth getting to know right up front. > > I started this same journey as a summer college student in 1967 at Florida > Power where I had late night access to an IBM 360 model 30 with standalone > operating systems like BOS and TOS. But they executed the same basic > prroblem state instructions such as STM, BALR, LA, SVC, etc. > > In 1980 I bought my first Radio Shack TRS-80 personal computer with 64k > Z80 chip and CP/M operating system. I thought I had died and gone to > heaven having my own "mainframe" at home 24/7. Over the next few years I > developed my first mainframe assembler and emulator written in Z80 > assembler. It executed about 25,000 360 instructions per seoond on a 4 > MHZ Z80 8 bit chip. I ported it to IBM PC with Intel 8086/8087 chip in > 1984 and published PC/370. > > In 2004 I retired from full time work as a systems programmer, and started > work on z390 written entirely in J2SE Java. Today this portable > mainframe tool executes over 30 MIPS on an Intel i5 chip. > > I hope you find this useful. Seveal universities are using z390 which > also includes the ASSIST extended instructions described in Struble's > book, and there are examples included. > > Don Higgins > d...@higgins.net >
