Re: C128D

From: Howard Herman (
Date: 1999-03-19 08:05:51

Nicolas Welte wrote:
> Howard Herman wrote:
> > Subsequently, when Basic 8 programs began to appear both the flat C128
> > and C128D had display problems, and I upgraded both computer VDC chips.
> > As I recall these were relatively expensive, something like $30(US) each
> > at the time.  But the new VDC's let me successfully run all the new
> > Basic8 programming.
> Do you have version information of the VDC chips you removed and the
> ones you got as a replacement? I know that there are some issues when
> programming bitmap graphics with the very early 8563 VDC, but it can be
> fixed in software. Since the 128DCR was never shipped with a 8563 at all
> but with a 8568 I'm very curious why you had to upgrade that chip.
> The VDC has a software version register, and you can use it to determine
> your VDC version from software:
> Chip                  version
> 8563R7 and lower         0       (this needs special treatment for
> bitmap)
> 8563R8 and higher        1
> 8568                     2
> You get the version by reading the lower 3 bits of the VDC status
> register at $D600. PRINT (PEEK(DEC("D600")) AND 7) should do this.

PRINT returns a 2.  (I thought I had the old chip here, but could not
locate it.)

The specific reason I upgraded/changed this chip was that I could not run
Wizard 128.  Wizard was a front-end interface for the GEnie online
service.  One of its nice features was that it allowed a user to use a
mouse to make selection choices.  It offered a minimal graphic type
interface, with selection boxes that could be clicked, etc., to do the
various online tasks.  All in all a nice online program for its time.  

It was written by Bill Coleman, who also wrote a C128 version of RSCards,
a graphical program that allowed the user to play several card games
online with other GEnie users.  As you were dealt a hand, the cards
popped up on your screen, not unlike today's Window's Solitaire.  And,
the graphics were remarkably good.  The nice bit about RSCards is that
there were versions written for the Amiga, MS-DOS and the MAC, so that it
did not matter what type computer you were running.  This was during the
days when we had thousands and thousands of CBM subscribers on the
service.  Alas, as with most all online services at that time, it was a
closed system.  (My access to Internet in those days is a longer story,
for some other time.)

On GEnie I was one of several sysops in the CBM area, and had to be able
to run Wizard.  With the new replacement chip, Wizard ran fine. 
                    ___  ___  ___      ___  ___
                   / //_/ // / //     / //_/ //
Howard Herman     / ___  // / //___  / ___  //    /_// /_// /_____// /_// /_//
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