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Topic 70 Sun May 29, 1988
W.DRESCHER at 16:03 EDT
Sub: New C64C bug
S The new sound chip in the 64C is not compatable with some software, .
10 message(s) total.
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Category 1, Topic 70
Message 1 Sun May 29, 1988
W.DRESCHER at 16:08 EDT
I have found that the new 64C has a new motherboard and seems to have a
different sound chip . Programs like THE THREE STOOGES and othr ers that
have digitized sound do not work properly. Has anyone found this problem with
other games? I really would like to know why Commodore screwed up the 64C. I
sold my 'old' 64 for the new style keyboard, only to find I traded 'down' to
a computer that is not compatable with some of my software. Wayne
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Category 1, Topic 70
Message 2 Tue May 31, 1988
D.SCHMOLDT [Dave/SysOp] at 00:49 EDT
Wayne,
A member of our user group put an article in the last newsletter comparing
the chips in the old and new 64s. They are almost completely different. He
wasn't even able to find a SID chip in the 64c, it was disguised so well ....
or combined with other chips.
I hadn't heard of any compatibility problems yet. What does the 64c do (or
not do) when it runs into digitized sounds? Does it not even play them, or
do they just sound strange? I can't believe Commodore would make any
modifications to the SID chip addresses and such.
Dave
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Category 1, Topic 70
Message 3 Tue May 31, 1988
W.DRESCHER at 22:45 EDT
The digitized sound (as in 3 Stooges) is very low in volume compared to the
music. I can hardly hear the digitized sound when the music is up a at
a good volumn me. The at ruins this particular game. In the h 'hit' and
'slap' part of the game you need to hear the sound and you can't unless you
crank the monitor all of the way up. In TEST DRIVE the DI digitized sound of
soung d of the car in the intro is lost....no biggy, but I keep wondering
what else I will be missing in the future. Wayne......thanks for the reply,
it was interesting
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Category 1, Topic 70
Message 4 Wed Jun 01, 1988
D.SCHMOLDT [Dave/SysOp] at 01:18 EDT
C-64 and 64C
--Two Different Critters--
by Gary Brinton, Commo-Hawk User Group, Cedar RApids, Iowa
According to some articles I've read, I tended to believe that the 64C
is little more than a C-64 in a new wrapper. Although both machines
operate the same, there are significant differences in the chips. Planning
on buying one of those $24.95 super kernal chips? If you have a 64C,
forget it. There may not be a discrete kernal chip in your machine.
Certainly it's not the same chip that's in the C-64. If you're thinking
about adding another 6581 SID chip to your 64C to play stereo music with
the new SidPack software, forget that too. There's no 6581 in there. You
can't follow any of the existing instructions on how to alter your machine.
Commodore took out many of the cheap (jelly bean) chips like the 74LS
series and combined them into big, and probably super expensive chips. One
such is the 251715-01, a 64 pin monster. They took out so many that they
were able to shrink the board width by an inch and 1/2. Also gone is the
6510 microprocessor. Anyone know where it's buried?
What this means from the service angle is that when a large chip goes
bad on the 64C, that chip probably isn't available from places like Jameco.
You may have to go to Commodore directly. And, if you've invested $19.95
in a Howard Sams diagram for the C-64, it won't work for the 64C. There
isn't any place I know of where you can get a complete diagram of the 64C.
Maybe Commodore has it?
On the positive side, fewer chips means less time spent hunting down
bad ones. Finding which chips do what, is another matter.
The following is a chip list in both machines. I don't know what each
of the 64C chips does, but from the list, you can get an idea of the
integration.
64C C-64
(Big Chips)
6526 (2) 6526 (2) (Interface)
901225-01 901225-01 (Char Rom)
-------- 901226-01 (Basic Rom)
-------- 901227-02 (Kernal Rom)
-------- 906114-01 (PLA)
-------- 6510 (Micro Processor)
-------- 6567 (Video)
-------- 6581 (SID)
8500 -----------
8560 -----------
8562 -----------
251715-01 -----------
251913-01 -----------
(Small Chips)
7406 7406
MC14066 MD14066
MN2114 2114L-30L
74LS14 --------
74LS508 --------
86458N --------
8701 --------
8631FU001 (2) --------
------ 74LS08
------ 74LS74
------ 74LS139
------ 74LS193
------ 74LS257 (2)
------ 74LS258
------ 74LS373
------ 74LS629
------ HM4864 (8) (Ram)
------ NE556
------ MC4044P
I didn't include the RF modulator chips, because I didn't want to open
the boxes.
If anyone knows where we can get more information about the 64C, please
let me know or print it in the next newsletter. The articles I've read
contain none of the above information.
-G Brinton
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Category 1, Topic 70
Message 5 Thu Jun 02, 1988
W.DRESCHER at 07:31 EDT
Also, try the game TEHTH FRAME. The ball sounds like a 'jet' rather than a
bowling ball going down the lane. Must be a filter change in the 64C
the 64C. Wayne
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Category 1, Topic 70
Message 7 Thu Jun 09, 1988
W.DRESCHER at 07:34 EDT
Well, I fixed my problem, sort of. I found a friend with an old 64 and he
traded motherboards with me. It took some work, but I put the old board in my
64C case. It's too bad I had to suffer just to make my 64 compatable with
it's own software. I wrote to C= about my (our) problem but I don't really
expect an answer. Does anyone know what address would be the best to write C=
about this rticular problem? Maybe they will come out with a 'new' 64 for us
to buy. They'll probably call it 'Classic Commodore 64'! Wayne
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Category 1, Topic 70
Message 8 Sat Jun 11, 1988
E.R.FLINN at 23:22 EDT
There is, it seems, yet another complication here. I have an early 64C,
and have opened it and found it to have a full-size motherboard, and the
traditional assortment of 64 chips. It seems that only the later 64Cs have
the half-size board and the conglomerated chips. My 64C is also held
together with obnoxious Torx screws, but these yielded easily to a tiny allen-
head driver I had lying around.
The claims that the 64C is identical in all internals to the 64, made at
the time the 64C was first released were, apparently, true at that time.
<ed>
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Category 1, Topic 70
Message 9 Sun Jun 12, 1988
W.DRESCHER at 23:09 EDT
Yes, I HAD a new 64 with the old motherboard in it. It blew out on on me,
so I had to bring it back to the store for a new one. I should hac ve stuck
with it because I got a new type motherboard in return I hope C= will fix
the sound problem Wayne
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Category 1, Topic 70
Message 10 Tue Aug 02, 1988
W.DRESCHER at 07:35 EDT
Well, I heard from Commodore, finally They told me I must have a bad sound
chip and I should go to the place that I got the computer and get a new one.
Well, since I had the problem I got 2 different ones and they both have the
same problem The THREE STOOGES game will NOT work right. The digitized
sound can barely be heard. Even many digitized programs from GEnie won't
work. C= told me they tried their 128's with digitized sound and it processed
fine. The sound at the beginning of TEST DRIVE is completely non-existant.
The bowling ball in TENTH FRAME sounds like an F-15 jet fighter when it rolls
down the alley. If anyone with a C64C can add to his list (this list) any
software that doesn't work properly or even write to C= yourself I would
appreciate it. Wayne
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