Topic: Andre Fachat's PET 65816 cpu card

[RobertB]

     Congratulations to Andre Fachat!  He has created the world's first 65816 cpu card for the Commodore PET.  To read about it, go to

          http://www.6502.org/users/andre/cbmhw/pet816/index.html

               Truly,
               Robert Bernardo
               Fresno Commodore User Group
               http://videocam.net.au/fcug
               July 24-25 Commodore Vegas Expo 2010 - http://www.commodore.ca/forum
               and click on ComVEX

[airship]

Can a C128 version be far behind?!? 

[Hydrophilic]

That looks awesome!  I'm not fortunate enough to own a SuperCPU/128, so my thinking on this could be wrong... but they both use the same CPU right.  From the page link above, it seems one difference is Andre's model runs at 12MHz while I thought SuperCPU runs at 16MHz?
 
But even at 12MHz, with 1MiB RAM and 16-bit instruction set, a C128 version would truly rock.  So Andre's model plugs directly into the 6502 CPU socket.  Well from my recollection, the C128 does not have either CPU in a socket.  Neglecting that, the 8502, like the 6510 of the C64, has onboard I/O port which is not present on original 6502... so a PIA or VIA or CIA or something similar would also be needed for a C128 version?
 
I also hear that SuperCPU/128 also has a special MMU?  That all sounds like a bunch of extra stuff compared to Andre's version.
 
But still, a C128 version would be awesome considering the price and (in)availibility of SuperCPU/128.

[redrumloa]

The SuperCPU 128 has a MMU card and runs at 20mhz.

[RobertB]

...but they both use the same CPU right.

     Yes, they do.

From the page link above, it seems one difference is Andre's model runs at 12MHz while I thought SuperCPU runs at 16MHz?

     Hmm, from the Western Design Center website, the W65C816S runs at 14 MHz.  The SuperCPU's 65816 was overclocked to run at 20 MHz.

That all sounds like a bunch of extra stuff compared to Andre's version.

     Heh, all that extra stuff is needed to maintain compatibility, usability, etc.

              Truly,
              Robert Bernardo
              Fresno Commodore User Group
              http://videocam.net.au/fcug
              July 24-25 Commodore Vegas Expo 2010 - http://www.commodore.ca/forum
              and click on ComVEX

[BigDumbDinosaur]

Hmm, from the Western Design Center website, the W65C816S runs at 14 MHz.  The SuperCPU's 65816 was overclocked to run at 20 MHz.

At one time, WDC sold the '816 in various speed grades, up to and including 20 MHz.  All current production is labeled at 14 MHz, but can run at 20 MHz.  Most of their support chips (65C22, etc.) are similarly capable.  The problem with running the MPU at 20 MHz is, for most hobbyists, one of getting glue logic to keep up.

[RobertB]

At one time, WDC sold the '816 in various speed grades, up to and including 20 MHz.

     Right.  For example, my Apple IIGS had a 65816 running at 2.8 MHz.. The Transwarp GS accelerator board inside it now uses a 65816 running nominally at 6.25 to 7 MHz..

             Truly,
             Robert Bernardo
             Fresno Commodore User Group
             http://videocam.net.au/fcug
             July 24-25 Commodore Vegas Expo 2010 - http://www.commodore.ca/forum
             and click on ComVEX

         

[BigDumbDinosaur]

One of my little sources of amusement is building useless pieces of electronic hardware.  Here's a picture of a single-board computer I built around a W65C816S.  This one is stable up to 12 MHz, after which timing violations on the I/O hardware start to occur.  The MPU itself has no trouble operating at 20 MHz.  The glue logic is 74AC, but I have since changed it to 74ABT where possible to keep prop delays to a minimum.

[Hydrophilic]

That's a really nice looking computer! (envy).  With 16bits at 12+ MHz, I find it hard to believe it is useless.  VIC2 interlace mode is something closer to useless.

[BigDumbDinosaur]

That's a really nice looking computer! (envy).  With 16bits at 12+ MHz, I find it hard to believe it is useless.  VIC2 interlace mode is something closer to useless.

It's not that hard to build.  The only trickiness is in soldering the SRAM (SOJ package) to the board.  The rest is through-hole stuff.  If you want to build one look at the following:

Schematic, page 1
Schematic, page 2
Schematic, page 3
Schematic, page 4
Schematic, page 5

Here's the PCB layout.  It is a 4-layer board.

The parts list is a bit out of date.  Where possible, I substituted 74ABT logic for 74AC.

So far, the ROM has a full initialization sequence and the beginning of a machine language monitor.  BTW, the DUART can independently run each serial port at up to 115.2 Kbps bi-directionally.

[RobertB]

Congratulations to Andre Fachat!  He has created the world's first 65816 cpu card for the Commodore PET.

     Holy cow!  Andre Fachat now has a PET 65816 card running at 10 MHz. on an actual PET, a PET 8296 to be exact.  To read up on the latest, go to

          http://www.6502.org/users/andre/adv65/pet816/index.html

                   A lot has changed since this was reported in May,
                   Robert Bernardo
                   Fresno Commodore User Group
                   http://videocam.net.au/fcug
                   The Other Group of Amigoids
                   http://www.calweb.com/~rabel1/
                   Southern California Commodore & Amiga Network
                   http://www.sccaners.org

[Shaun_CCC(UK)]

Does this hardware work with just 80-columns machines, or 40-cols machines too?

Regards,

Shaun.

[RobertB]

     Unknown.  He's only tried it out on a real PET 8296.

            Truly,
            Robert Bernardo
            Fresno Commodore User Group
            http://videocam.net.au/fcug