Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!mit-eddie!uw-beaver!tektronix!tekcrl!tekgvs!toma
From: toma@tekgvs.LABS.TEK.COM (Tom Almy)
Newsgroups: comp.lang.forth
Subject: Re: 32-Bit FORTH
Message-ID: <5445@tekgvs.LABS.TEK.COM>
Date: 26 Jun 89 16:12:40 GMT
References: <865@pcsbst.UUCP>
Reply-To: toma@tekgvs.LABS.TEK.COM (Tom Almy)
Organization: Tektronix, Inc., Beaverton,  OR.
Lines: 39

In article <865@pcsbst.UUCP> rht32!hgw@pcsbst.UUCP () writes:
>Now, I want to port it to an environment where integers and
>addresses are 32 bit wide (since I want to address all of the
>memory in the machine).

>Since I am not familiar with 32-bit FORTHS, I have some
>questions:

I am familiar with two Forths from Laboratory Microsystems, Inc, 
PC/Forth+ (which is a 32 bit Forth that runs in a 16bit 8086 
environment, linearizing the !@#$ segment addresses) and UR/Forth 386,
which is a 80386 protected mode Forth.  

>o  Does a 32-bit FORTH imply that a 16-bit data type is not
>   available?

By no means!  You need them for accessing data files written by 16
bit programs, and (at least for MS/DOS) to communicate with the OS.

>o  How are 16-bit loads & stores implemented?
>   (perhaps S! and S@ ?!)

We are entering the world of non-standards  here.  LMI uses W@ W! and
UW@, because in Intel nomenclature, 16 bit data is Word data.  Note that
W@ does a sign extension, while UW@ is unsigned.

>o  How are character strings stored in memory?
>   (4 characters per word, or 1 character and 3 chars free)

4 characters per word.  C@ and C! work just like in their 16 bit Forth
counterparts.

>o  Is there any standard for 32-bit FORTHS out there?

Not yet.  But the new ANSI Forth Standards Team is addressing the issue.

Tom Almy
toma@tekgvs.labs.tek.com
(Claimer: I do have a financial connection with LMI, but I'm not getting rich)