IBM System 3 / was Re: VTL/Dutchess logic

Russ Bartlett arcbe2001 at
Mon Oct 11 19:02:20 CDT 2010

Correction The System/3 was the first RPG II machine and the System/34 also used RPG II whereas the System/38 introduced RPG III,  The problem with the logic cycle was that it didn't fit well into the interactive model environment.  Interestingly Honeywell (Italy I think) introduced a RPG III compiler for their DPS System 4000 IDBS4 was their attempt at a relational database as found on System/38.  THe IBM 360/20 was the predecessor to the System/3 and unlike the other 360's was a 16 bit machine with a reduced instruction set.


--- On Mon, 10/11/10, Rich Alderson <RichA at> wrote:

From: Rich Alderson <RichA at>
Subject: RE: IBM System 3 / was Re: VTL/Dutchess logic
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at>
Date: Monday, October 11, 2010, 2:51 PM

From: William Donzelli
Sent: Monday, October 11, 2010 11:36 AM

>> Just curious about the architecture: at the programmer's level did it look
>> like a primarily 8-bit machine, or a 16-bit machine which always processed 2
>> bytes in sequence, or it would best be described as mixed 8/16?

> S/3s worked with strings of bytes in memory, basically. Very non-traditional.

Not for IBM.  The 1401 was very much a character-oriented machine.

The S/3 was not, in general, programmed by user programmers in anything other
than RPG III, which went on to be the programming model for the System/3x and 
AS 400 families; IIRC the original RPG was a 1401 program product.

Rich Alderson
Vintage Computing Sr. Server Engineer
Vulcan, Inc.
505 5th Avenue S, Suite 900
Seattle, WA 98104

mailto:RichA at
mailto:RichA at


More information about the cctech mailing list