rs0@beach.cis.ufl.edu (Bob Slaughter) (10/26/89)
I have a friend who wants to write a 6502 based forth, and he needs the source listing and such for this. Where can he go to find it? While the machine does have some implementations already, he wants to start from scratch. (see previous posting about minimal machine implementation :} ) Thanks in advance! -- * Bob Slaughter * This space for rent * * InterNet#1: Haldane@Pine.Circa.Ufl.Edu * Call 1-800-FOR-RENT * * InterNet#2: rs0@beach.cis.ufl.edu * Model Railroading * * Bitnet: Haldane@UFPine * is Fun!! *
bouma@cs.purdue.EDU (William J. Bouma) (10/27/89)
In article <21108@uflorida.cis.ufl.EDU> rs0@beach.cis.ufl.edu (Bob Slaughter) writes: >I have a friend who wants to write a 6502 based forth, and he needs >the source listing and such for this. Where can he go to find it? >While the machine does have some implementations already, he wants to >start from scratch. (see previous posting about minimal machine >implementation :} ) > Uh, if he wants to start from scratch, why does he need a listing? I am sure you can get a listing from the Forth Interest Group. I don't have the address available, but can get it for you if you drop me a note. It will probably cost ~$10. I am not sure why anyone would want to implement such a minimal machine, at least in software. It is bound to run reletively slow as there will be more threading to get to the few primitives. It is an interesting thing to think about, but why implement? Especially why write it in assembler? Since it is going to be slow anyway, use a friendly language. -- Bill <bouma@cs.purdue.edu> || ...!purdue!bouma
ZMLEB@SCFVM.BITNET (Lee Brotzman) (10/29/89)
William J. Bouma <bouma@PURDUE.EDU> writes: >In article <21108@uflorida.cis.ufl.EDU> rs0@beach.cis.ufl.edu (Bob Slaughter) > writes: >>I have a friend who wants to write a 6502 based forth, and he needs >>the source listing and such for this. Where can he go to find it? >>While the machine does have some implementations already, he wants to >>start from scratch. (see previous posting about minimal machine >>implementation :} ) >> > > Uh, if he wants to start from scratch, why does he need a listing? > I am sure you can get a listing from the Forth Interest Group. I > don't have the address available, but can get it for you if you > drop me a note. It will probably cost ~$10. > > I am not sure why anyone would want to implement such a minimal > machine, at least in software. It is bound to run reletively slow > as there will be more threading to get to the few primitives. It > is an interesting thing to think about, but why implement? Especially > why write it in assembler? Since it is going to be slow anyway, > use a friendly language. >-- >Bill <bouma@cs.purdue.edu> || ...!purdue!bouma I once was a guest lecturer for a series of advanced Forth classes. It is impossible to describe the inner interpreter without using some form of assembly language and a LOT of pictures showing what's going on. It is impossible to write a Forth machine without clear understanding of the inner interpreter. I think this is why the plea for a listing of some sort was raised. The inner interpreter is a very simple concept once one has expended some effort delving into it. Almost every gut-level Forth programmer I have spoken with will attest to his moment of enlightenment when the inner interpreter, and all that comes from it, is understood. As to why anyone would actually want to implement the "Forth Minimal Machine", that should be obvious: TO MAKE SURE THE DAMN THING WORKS. The only way to be sure all the code that has been presented works is to try it. This is the Forth philosophy. You get an idea; you try the idea; if the idea works, great; if the idea doesn't work, you find the mistake and learn from it. The weak point of the Forth minimal machine that I have noticed is that there is no input or output in any form. Assume the dumbest of serial interfaces (put a character in CHAROUT and get a character fom CHARIN) and go for it. -- Lee Brotzman (FIGI-L Moderator) -- BITNET: ZMLEB@SCFVM Internet: zmleb@scfvm.gsfc.nasa.gov -- The government and my company don't know what I'm saying. -- Let's keep it that way.