5pin or 8pin Video ports on C64?
Tim
Monitor. I can't tell if the lower quality one has a 5pin or 8pin video
port. But I suspect that is what it must be. Any way to find out or to
hack the port for better video output?
Tim
Michael Hunter
"Tim" <tjl...@mail.com> wrote in message
news:v8mutgt...@corp.supernews.com...
> I have 2 C64's (Breadbox) and on one the Video is better than the
other on a
> Monitor. I can't tell if the lower quality one has a 5pin or 8pin
video
> port. But I suspect that is what it must be. Any way to find out
or to
You could try using the same 5-pin cable on your other system. The
C-64's equipped with an 8-pin connector produce the same signals on
the same lines as the older 5-pin systems. The "seperated video" on
the machines equipped with 8-pins will not be used if you are using a
5-pin cable.
The quality of the screen's image also varies with each revision of
the VIC-chip. I have almost every major revision of the Commodore 64,
and the video quality is different on each one. The worst image is
produced by my earliest model, which is one of the first 10,000 made;
it's screen looks as if you are tuning it in with rabbit ears on a
stormy day (or during an electrical storm). This was a common
observation in the very early systems. I keep my old one around
mainly for novelty purposes. My more recent revisions receive the
heaviest use.
> hack the port for better video output?
You could probably replace the VIC-chip with another revision, and
attempt to re-create the seperated video function offered on the later
versions, but I don't know that it would be worth the effort. A
simple VIC-chip swap, may provide enough of an improvement for you.
My bread-box 64 with a rev. 2 kernal and 5-pin video produces
adequately clear images, but it is no-where near as bright and clear
as my Rev. 3 and higher systems.
Michael Hunter
mhu...@videocam.net.au
>
> Tim
>
>
Tim
"Michael Hunter" <mhu...@videocam.net.au> wrote in message
news:v8n115b...@corp.supernews.com...
looks blurry on the one, and crisp and clear on the other! What chip is the
VIC btw? I have a C64C Rev 3 MB (smaller PCB) can I use the VIC chip from
that one? (CIA is bad on that one) I actually took the MB from a old junk
Breadbox C64 and threw it into the C64C case, and this is the one with the
bad video!
Thanks
Tim
Michael Hunter
> Yeah I use a 5pin cable on both so it must not be what I thought.
The video
> looks blurry on the one, and crisp and clear on the other! What
chip is the
> VIC btw? I have a C64C Rev 3 MB (smaller PCB) can I use the VIC
chip from
The VIC chip is commonly labeled 6567 in the NTSC machines. PAL
systems should have a 6566 VIC.
I have swapped VIC chips between the R2 breadbox and R3 64c with no
problem, so I imagine that it should work fine. The final revision -
I think it is Rev 4 or Rev E - of the 64c (which had a narrower board)
may have a different type of VIC chip. If I am remembering correctly,
that VIC chip has two more pins. I could be completely wrong here;
afterall, I am going by memory :) I also believe that this particular
board used 64kx4 DRAM chips instead of 64Kx1 DRAM, allowing the main
memory to be provided by two chips (again, I could be wrong there too,
someone remind me if I am). The other 64c systems used boards that
are nearly identical to the older 64's.
The 6567 is usually located towards the right of the 64's board, and
usually by itself with only one small 8701 chip next to it. On some
machines, there will be a tin can covering it; on others, you'll only
see an outline where a box would be mounted.
If you have anything that is acting as a heat-sink (such as the tin
can's lid, or RF shield) make sure that it is making good contact when
you put everything back together. Use fresh heat-sink compound
(preferably not silicone based).
Let me know if I can be of further assistance.
Michael Hunter
mhu...@videocam.net.au
TjLaZah^
Well just learned that if a C64 has a 5 pin video port, it will have just
that! 5 pins only! Not a 8pin port with 5 pins active like I assumed.
Am I wrong???
Tim
Ray Carlsen
> > port. But I suspect that is what it must be. Any way to find out or to
> > hack the port for better video output?
> Well just learned that if a C64 has a 5 pin video port, it will have just
> that! 5 pins only! Not a 8pin port with 5 pins active like I assumed.
> Am I wrong???
Tim,
I'm not sure what you're getting at, but both 5 and 8 pin DIN computer
A/V sockets are wired the same for those five pins. The eight pin socket
has one additional connection for separated chroma (color-only signal) and
two pins are not used (but one is connected to +5VDC and should therefore
be avoided). So, a five pin cable can be used with a computer with the 8
pin DIN socket with exactly the same results as if the computer had a 5 pin
socket. If there is a difference in performance, it must come from inside
the computer. As someone else mentioned, VIC chip versions have quite an
effect on performance and I've seen failing chips with reduced contrast
and/or smeared pictures. You get the best quality video from the eight pin
arrangement when used with the three-wire CBM cable into a monitor that
supports S-video, like the 1702. If all you have is a five pin DIN, then
the only option is standard composite (one wire) video. Bottom of the list
video quality is an RF connection to your TV set antenna input.
Ray
Tim
"Ray Carlsen" <rr...@u.washington.edu> wrote in message
news:Pine.A41.4.44.030403...@homer01.u.washington.edu...
What I am saying is that I was confused on the defferent C64s with 5/8pin
ports. Do all C64s have a PHYSICAL port on them with 8 pins (regardless if
they have 5 or 8 pins connected to the video inside) or do they have 2
DIFFERENT PHYSICAL ports, 5pin or 8pin?
I read a post that someone said his C64 has 5 pins on the port, so a cable
with 8 pins would not fit into the port!
My two breadbox 64s both have Physical 8 pin ports, so I guess it's the VIC
chip and not the Y/C video that is causing my slightly blurry video.
As a side note I own a 1702 and a 1084. I have the original CBM 3 RCA cable
that has 8 pins. When I plug the C64 into either monitor with the 8pin or
5pin Video cable the display is the same, no visible difference. One one
cable I get color and on the other I get B/W. I would of thought on the
5pin cable I would only get Color Composite. But I get both. So is the
5pin cable a Y/C cable?
I thought the 5pin aftermarket cables do not have Chroma/Luma!
Any explenation would be appreciated.
Thanks,
Tim
genewoods5
pin there is no Color out (Chroma signal output).
Here is a list of pins 1st 5 are the 5 pin
PIN TYPE NOTE
1 lum/sync luminance
2 GRD
3 audio out
4 video out composite signal output
5 audio in
6 Color out chroma signal output
7 NC NO CONNECTION
8 NC
If you are using 8 pin on a 1702 use the back inputs with Luminance and Color
out.With a 5 pin cable use the back inputs with Lum and Video out. Use the
front inputs with VCR or VIDEO game machine and some other computers.
Gene!
Ray Carlsen
> ports. Do all C64s have a PHYSICAL port on them with 8 pins (regardless
> if they have 5 or 8 pins connected to the video inside) or do they have 2
> DIFFERENT PHYSICAL ports, 5pin or 8pin?
Tim,
There are two separate versions of the 64. The earlier models have
only the 5 pin DIN (no separate chroma connection anywhere), and later
versions, including the C128 /D versions all have the 8 pin DIN which
gives the additional feature of separated Y and C (now called S-video).
> I read a post that someone said his C64 has 5 pins on the port, so a
> cable with 8 pins would not fit into the port!
That's correct. Even if you broke off the extra unused pins, the cable
would not work because there is no separated chroma in a 5 pin socket. You
would get a B/W picture and normal audio.
> My two breadbox 64s both have Physical 8 pin ports, so I guess it's the
> VIC chip and not the Y/C video that is causing my slightly blurry video.
It's possible, but two computers with that same problem would make me
suspect the cable first.
> As a side note I own a 1702 and a 1084. I have the original CBM 3 RCA
> cable that has 8 pins. When I plug the C64 into either monitor with the
> 8pin or 5pin Video cable the display is the same, no visible difference.
> On one cable I get color and on the other I get B/W. I would have thought
> on the 5pin cable I would only get Color Composite. But I get both. So
> is the 5pin cable a Y/C cable?
No, it is composite only. A two wire cable (if it was made for a C64) is
wired for composite no matter what computer it is plugged into, 5 pin or 8
pin sockets. The three wire cable is wired for separated Y/C -only-. Such a
cable must be used with a monitor that can accept Y/C (two separate wires
for luminance and chroma). Not all 1084s can accept Y/C inputs like the
1702 can.
> I thought the 5pin aftermarket cables do not have Chroma/Luma!
If you mean the -four- wire cable, it's not a Commdore product but was
originally used for audio only applications. The DIN was/is a standard in
Europe for audio interface. It doesn't connect to the chroma line (pin 6)
so it will not work for Y/C video. If I remember correctly, it connects to
video out, luminance out, audio out and audio -in-. Note that the audio
input line connects directly to the SID chip. That's why using a four wire
cable is risky. I blew two SID chips before I figured out why... accidently
grounding the input pin with the computer turned on! If you must use a four
wire cable, connect and disconnect plugs only with the computer turned off,
and cover any unused plugs with insulating tape or plastic sleeving
beforehand.
Ray