strangest systems I've sent email from

Norman Jaffe turing at
Tue May 24 15:53:25 CDT 2016

Without an MMU or a segmentation scheme, 16-bits = 64K. 
The 68000 is not a 16-bit processor, it's 32-bit, and exposed (ISTR) a 24-bit address. 
20-bits = 1M addresses, 24-bits = 16M addresses. 
You're confusing data bus width (8-bit) with address bus width (16-bit). 
----- Original Message -----

From: "Liam Proven" <lproven at> 
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at> 
Sent: Tuesday, May 24, 2016 1:29:48 PM 
Subject: Re: strangest systems I've sent email from 

On 22 May 2016 at 04:52, Guy Sotomayor Jr <ggs at> wrote: 
> Because the 808x was a 16-bit processor with 1MB physical addressing. I 
> would argue that for the time 808x was brilliant in that most other 16-bit 
> micros only allowed for 64KB physical. 

Er, hang on. I'm not sure if my knowledge isn't good enough or if that's a typo. 

AFAIK most *8* bits only supported 64 kB physical. Most *16* bits 
(e.g. 68000, 65816, 80286, 80386SX) supported 16MB physical RAM. 

Am I missing something here? 

I always considered the 8088/8086 as a sort of hybrid 8/16-bit processor. 

Liam Proven • Profile: 
Email: lproven at • GMail/G+/Twitter/Flickr/Facebook: lproven 
MSN: lproven at • Skype/AIM/Yahoo/LinkedIn: liamproven 
Cell/Mobiles: +44 7939-087884 (UK) • +420 702 829 053 (ČR) 

More information about the cctalk mailing list