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 Sweet 16 - because everybody loves registers 
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Joined: Mon Aug 14, 2017 8:23 am
Posts: 57
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
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Joined: Wed Jan 09, 2013 6:54 pm
Posts: 1206
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
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Joined: Tue Dec 31, 2013 2:01 am
Posts: 98
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
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Joined: Wed Jan 09, 2013 6:54 pm
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(Thanks! Here's an archived version in case tumblr evaporates.)


Sun Apr 14, 2019 6:53 am
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