Re: C-128 and Jeri board
Date: 2001-05-03 06:01:02

On Wed, 2 May 2001, Professor Dredd wrote:

> Again, I encourage you to have a look at the Apple II
> lineage. With each generation of Apple II, the
> engineers were able to consolidate more discreet
> components into LSI/VLSI chips. It went something
> like:
> Apple II
> Apple II+

These two are the same, aside from the inclusion of integer vs applesoft

> Apple IIe

The first usage of VLSI to consolidate the machine into a few ICs

> Apple IIc

I believe this is a somewhat modified slotless IIe.

> Apple IIe Platinum

More integration, numeric keypad

> Apple IIe Card

The IIgs actually came first, since the IIe card was designed for the mac LC
series.  Its highly integrated IIe "subsystem" was used in the IIe card,
stripped to a bare IIe.  Apple's largest error, I believe, was using a
hardware 65c02.  If they'd emulated the 6502, it would be so much faster ;)

> Apple IIgs

The highest level of the original apple ][ chipset.  One IC does it all. 
Video, dram interface, I/O decode, onboard I/O.. everything but the

> The "card" plugged into a Macintosh computer. It
> contain a chip which was an entire Apple IIe computer
> and disk controller reduced to one integrated circuit.

The disk controller was little more than a few shift registers and some
control logic ;)

> Each generation reduced more discreet components to
> integrated circuits. Each one added some new hardware
> features over its predecessors. Every computer in that
> list still kept about 90% backward compatibility with
> the original Apple II. At what point did this family
> tree no longer produce Apple II computers?

The "Mark Twain" prototype Apple IIgs.  This machine was equipped with two
30pin SIMM slots, an internal 3.5" 400k drive, and a heftier 8mhz 65816
(compare to the lowly 2.8mhz IC in the classic IIgs).  This machine was
scrapped during development, the prototypes showed up at flea markets and
were quickly snatched up by collectors, and had nonworking internal 3.5
drives.  Quite an impressive last breath for the apple II family if it were
released.  Especially when paired with the never-produced ethernet card.

> That's exactly what were doing here with Jeri's
> project you see. We (well, Jeri really) are
> integrating discreet components and adding advanced
> hardware features.

I believe its time for the c64 to grow up.  It was time when the c128 was
born, but the c128 wasnt enough, and the amiga was too much.  I think its
important to be able to run most c64 programs without a mode switch, and
have the capability of running it at a higher speed.

> By the way, your definition excludes the C-128 from
> the C-64 family because the C-64 motherboard and
> keyboard are not present. The C-128 actually uses
> hardware logic to emulate the C-64 environment. It's
> all done within the MMU. The only chips shared by the
> two different computers are the CIAs (and possibly the
> SID although that changed in the C-64 too)

As it did in the HMOS C128DCR (metal case).  They used the 8580 in the c64c
(C64BN/E) and the DCR, while the NMOS flat c128 and classic c64's (c64A/B/C/D)
used the classic 6581.

In the same, is the c64c (bn/e board) not a c64?  Its completely redesigned,
has a different MMU (I/O decoder as far as I'm concerned), and shares littel
beyond the compatibility wit the classic machine.


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