View unanswered posts | View active topics It is currently Thu Mar 28, 2024 7:15 pm



Reply to topic  [ 4 posts ] 
 Sweet 16 - because everybody loves registers 
Author Message

Joined: Mon Aug 14, 2017 8:23 am
Posts: 157
There has been a fair bit written about Sweet 16 - a 16-bit virtual processor devised by Steve Wozniak in 1976/77 in order to simplify the handling of 16-bit instructions on the Apple 1 - which was an 8-bit 6502 and was somewhat short of registers.

Woz devised a virtual 16 bit machine with a bank of 16, 16-bit registers located in the first 32 bytes of zero-page RAM.

Modern languages (specifically C) need a bank of general purpose registers and so the implementation of a 16-bit virtual machine on top of the raw cpu, was one way to simplify programming.

The details of Sweet16 can be found here http://www.6502.org/source/interpreters/sweet16.htm


Sat Apr 13, 2019 6:26 pm
Profile

Joined: Wed Jan 09, 2013 6:54 pm
Posts: 1780
16 is a good number of registers! (OPC, MSP430, ARM,...) Although of course 8 is also a choice with some history.


Sat Apr 13, 2019 7:28 pm
Profile

Joined: Tue Dec 31, 2013 2:01 am
Posts: 116
Location: Sacramento, CA, United States
Charlie Hitselberger loves golfing around with his Pettil, and came up with a couple of cool observations and insights about Sweet16 here:

Mike B.


Sun Apr 14, 2019 5:58 am
Profile

Joined: Wed Jan 09, 2013 6:54 pm
Posts: 1780
(Thanks! Here's an archived version in case tumblr evaporates.)


Sun Apr 14, 2019 6:53 am
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 4 posts ] 

Who is online

Users browsing this forum: AhrefsBot and 8 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group
Designed by ST Software