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Can someone explain the '16' in 'X16'? I can't find an explanation anywhere.

It seems clear that the machine was always intended to be 8-bit, or as close to 8-bit as possible.

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If you have watched the second video of "Building My Dream Computer", it was originally called "Commander 16" with "Commander" as a placeholder term with similar meaning to "Commodore, but ended up as permanent name. The 'X' in front of '16' was added to avoid confusion with C16, which is a low-cost version of Commodore Plus/4 with 16 kilobytes of RAM.

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1 hour ago, StinkerB06 said:

I guess because it has 16 PSG channels?

That's an even later retcon than because it has a 16bit address space.

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On 10/10/2020 at 6:09 PM, BruceMcF said:

It has a 16bit address space, over which your command Xtends.

Wow. Good one. )

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On 10/9/2020 at 7:14 AM, isedwards said:

Can someone explain the '16' in 'X16'? I can't find an explanation anywhere.

It seems clear that the machine was always intended to be 8-bit, or as close to 8-bit as possible.

Here's my contribution to the made-up reasons.

The computer is named X16 because it has two separate 8 bit busses. The 65C02 lives on the system bus, and VERA has its own 8 bit bus with 128K of independent video memory. 

As to the real reason, Lorin already touched on it...

The original design was intended to use a 65C816 CPU running at 20MHz. The team wanted a name that fit the 16-bit nature of this computer, so came up with Commander X16. 

However, the design of the computer got too complicated, and David became discouraged with the extra silicon needed to decode the address bus. So the team dropped back to an 8 bit CPU and came up with the banking system that gives the Commander up to 2MB of banked RAM. (The 65816 can handle 16MB of RAM.)

That's how I remember it from the Facebook group and David's videos on the subject. 

 

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Ah, the difference between history and marketing. Yes, the 65816 (either name or extended 16 bit operations on the eight bit bus ... and in reality mostly 8bit registers, as 16 bit operations on the A, X, and Y operations typically function a byte per cycle) is the historical origin of the name.
 

"Named in honor of the 16bit address bus over which your Command Extends" is marketing.

 

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4 hours ago, BruceMcF said:

Ah, the difference between history and marketing. Yes, the 65816 (either name or extended 16 bit operations on the eight bit bus ... and in reality mostly 8bit registers, as 16 bit operations on the A, X, and Y operations typically function a byte per cycle) is the historical origin of the name.
 

"Named in honor of the 16bit address bus over which your Command Extends" is marketing.

 

Personally, I'm just happy you can do a 16 bit add with one operation. That alone really makes things easier.

On the other hand, you have to remember what mode the CPU is in: emulation, 8 bit, or 16 bit, or subroutines end up doing things very wrong.

 

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21 hours ago, BruceMcF said:

Named in honor of the 16bit address bus . . .

. . . to carry on his spirit? )

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Here's my contribution to the made-up reasons.
The computer is named X16 because it has two separate 8 bit busses. The 65C02 lives on the system bus, and VERA has its own 8 bit bus with 128K of independent video memory. 


Technically the VERA is 32 bit. It fetches 32 bits at a time from VRAM and fills its line buffer. This defines the layer and sprite limitations. But it does present to the system bus as an 8 bit address space.


Sent from my iPhone using Tapatalk

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