> The System 4 machine architecture was the same as the 360[1] but > the operating system, the System 4 DOS, was a bit like IBM DOS > (now VSE) but different. Customer programs tended to be written in > Assembler because the COBOL compiler was, at the time, the early > '70s, rather new.
System 4 J, if memory serves. The I/O was different - CCW formats and such. I used the 4/50 at ICL Forest Road, Feltham to write a package converting KeyEdit 1000 captured data into ICL's weird "coded variable" format - basically a way of omitting null fields to save space. I think there were a couple of additional instructions - "Add Immediate" comes to mind. Purely interpretive execution has been done before and published - I remember a book called "A Compiler Generator" in the early 1970s that contained the complete source code for emulation of /360 code on a /360 - the idea being that you could trace every instruction. -- Phil Payne http://www.isham-research.co.uk +44 7833 654 800 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
