Re: nFORTH v2.3
- To: <MISC>
- Subject: Re: nFORTH v2.3
- From: "Stas Pereverzev" <stas@xxxxxxxx>
- Date: Sat, 20 Feb 1999 12:54:34 +0300
>Comments, folks?
You need only five instructions, not 16. They are:
ALU:
1. nand
2. shr
RAM:
3. store ( addr n -- )
4. lit ( -- n )
CONTROL:
5. ncret \ JUMP to addr in N, if carry flag isn't set in T,
\ also drop both T and N
Also, if PC is memory variable (or can be addressed as memory variable)
we can awoid "ncret" instruction:
In that case we sholud use NCSTORE instead STORE:
ncstore (addr n flag -- )
ncstore (addr n 0 ) - same as store,
ncstore (PC n -1 ) - same as ncret
We need only 2 bits per instruction in that case.
That all folks ;-)
Stas.