[comp.sys.apple2] zip cpu

c056hdh@utarlg.uta.edu (Honda Hwang) (06/07/91)

 is the cpu on ZipGS the same kind as TWGS..? I mean made by WDC.
if so does that mean I can get a 9-10mhz 65816 that is more readly available
now and plug it in my TWGS (+4x mhz clock crystal) for an upgrade..?

------ 
 Honda Hwang

 C056HDH@UTARLG.UTA.EDU

toddpw@nntp-server.caltech.edu (Todd P. Whitesel) (06/07/91)

c056hdh@utarlg.uta.edu (Honda Hwang) writes:

> is the cpu on ZipGS the same kind as TWGS..? I mean made by WDC.
>if so does that mean I can get a 9-10mhz 65816 that is more readly available
>now and plug it in my TWGS (+4x mhz clock crystal) for an upgrade..?

Yes and no. The cpu in the ZipGS is made by WDC, but 9-10 mhz parts are still
not available in reasonable quantities yet. Zip buys lots of 7-8 rated parts
and hand picks the 9 and 10 mhz ones. I am running a Zip-provided 8-rated
part at 10 mhz and it works fine.

Todd Whitesel
toddpw @ tybalt.caltech.edu

whitewolf@gnh-starport.cts.com (Tae Song) (06/13/91)

Honda Hwang writes...
| is the cpu on ZipGS the same kind as TWGS..? I mean made by WDC.
|if so does that mean I can get a 9-10mhz 65816 that is more readly available
|now and plug it in my TWGS (+4x mhz clock crystal) for an upgrade..?

Yes, the Zip and the TWGS uses the same 65816 CPU.  The 9+Mhz CPUs are called
"shmoo" parts, you can get them to run faster by increasing the stanard
voltage (5v) to something like 5.5, but not 6v (which, BTW well destroy the
CPU)... you just have to keep the voltage under 6v.  The Zip has all the
connections and places to solder parts do you can supply a ~5.5v to the CPU.

You can send your Zip back to Zip and have them upgraded.  Upgrading is pretty
hair if you don't know what you are doing, especially for the CPU.
  
INET: whitewolf@gnh-starport.cts.com
UUCP: crash!gnh-starport!whitewolf
ARPA: crash!gnh-starport!whitewolf@nosc.mil

toddpw@nntp-server.caltech.edu (Todd P. Whitesel) (06/15/91)

whitewolf@gnh-starport.cts.com (Tae Song) writes:

>Yes, the Zip and the TWGS uses the same 65816 CPU.  The 9+Mhz CPUs are called
>"shmoo" parts, you can get them to run faster by increasing the stanard
>voltage (5v) to something like 5.5, but not 6v (which, BTW well destroy the
>CPU)... you just have to keep the voltage under 6v.  The Zip has all the
>connections and places to solder parts do you can supply a ~5.5v to the CPU.

Yes, but If you are smart and buy the >9V part from Zip then what you will get
is a hand-picked part from an 8 mhz shipment that does in fact run at 10 Mhz
with the standard 5 volts. I have one running at 10 and it says 8 on the chip;
haven't had any problems I could trace to the Zip yet.

BTW, Soldering the crystal in is a hell of a lot more reliable than socketing
it. You could use precision machined sockets (which cost a buck instead of 30
cents, or thereabouts) but when it comes down to it nothing is more reliable
than a good solder joint.

Todd Whitesel
toddpw @ tybalt.caltech.edu