Edited post S video with audio out cable to Commodore 1902A model monitor needed.

Edited post S video with audio out cable to Commodore needed
This edited version fully replaces my prior post at vintage-computer.com here
From S video with audio outs to Commodore model 1902A input I been interested in buying or making such a cable if possible I am not sure how to wire it if I was to make one or have one made for me. I though it would be nice for using a DVD player or DVD recorder or camcorder or my note book computer which has s video out and head phone out for audio with. I would think that this would be by standard a line level output that would not damage the hardware or cable to try different wiring configurations with it just may not work if wired wrong or not work correctly. I want to go from 4 pin male s video on one end with also a 1/8 inch stereo male for audio to a 8 pin or 6 pin commodore DIN male on the other end of the cable for audio and video, provided that the 6 pin would handle s video with audio. The Commodore C128 users guide seemed to be incorrect on the wiring of its 8 pin din connector. Has anyone tried this before and got it to work okay? Is there any where I can buy such a cable or cable that could be adapted to fit my needs and if yes where? Would I need to use the 40 column or 80 column or does it make any difference and if it would make a difference what difference would it make? I have a s video cable for using a Commodore computer with audio with a TV set though it does not work in reverse for my other purposes such as with a camcorder etcetera. Please be specific as to what parts are needed cable impedance etcetera. Replies to my user name are more likely to get a reply from me as they go to my email address I get to many forums to check for replies to get time to check them all or you can copy and paste and reply at the forum and to my user name. Are Commodore monitor DIN inputs standard?

Pinout of the Commodore monitor:
http://www.zimmers.net/cbmpics/cbm/monitors/1902a/pinout.html

S-video pinout:
http://pinouts.ws/s-video-pinout.html

The monitor is only mono, so you'll have to tie your stereo inputs together.

-Ian

How is the 40 column input on the Commodore model 1902A monitor wired

How is the 40 column input on the Commodore model 1902A monitor wired

How is the 40 column input on the Commodore model 1902A monitor wired? I believe the reply only shows the 80 input. more dependable way to reply by clicking on my user name. The 40 column cable for the C128 to 1902A monitor I believe is the one that has the screws so one can thread to the computer and the other end on my goes to the input on my Commodore model 1902A monitor. I think the wiring diagram sent by thread to this post is for the 80 column input only so far to March 1, 2011 at 7:25 PM PST.

The pinouts RetroHacker posted were simply monitor inputs and a general S-Video pinout, enabling you to connect your DVD or PC output to the monitor. As far as the monitor is concerned, as long as the scan rates are the right ones, it doesn't care how many columns or pixels the video signal consists of.

The C128 has 40 column composite and Y/C (~= S-Video) outputs through a 7-pin DIN connector, same pinout as the C64.
http://pinouts.ru/Video/C128C64CVideo_pinout.shtml

The only way to get a 80 column display on your 1902 monitor is to use the composite video signal (pin #7) on the RGBI output. It will only be monochrome as your monitor lacks RGB inputs.
http://pinouts.ru/Video/C128Rgbi_pinout.shtml

The reason why we don't reply by PM is it is easier to follow the discussion in the forum, as well as there is a quota on PM's which some of us may prefer to reserve for truly private matters. Sorry if that is a problem for you.

S Video wiring to Commodore 1902A monitor for connection of camcorders, ecetera.

S Video wiring to Commodore 1902A monitor for connection of camcorders, ecetera.

If the C128 owners manual I have is correct he female DIN type video connector on the Commodore C128 computer per the Commodore C128 owners manual is a 80 column connector and the connector which connector port has threading for 2 screws to hold the connector in place then must be process of elimination be the 40 column connector when I have done a goggle product search under 40 column and 80 column cables for the C128 the results have been the same as I stated above however some people have told me in reverse of the above as to which is 40 column and 80 column cables. One way to check this out to some extent is only plug in one of the 2 cables and put the computer in only one of the 2 modes at a time to see when it is in 40 column mode do you get a signal through it to the monitor if not try putting the computer in 80 column mode to see if you get a signal through it. If one can tell me how to go from 40 column to 80 column that would help. The cable I bought premade with the DIN round shaped male cable connector will go from the C128 to a TV with 4 pin s video input though would not work in reverse or for going from S Video out to Commodore 1902A monitor input.

How does one change on a C128 from 80 column mode to 40 column mode and vice a versa?

Is it true it should not hurt the cables or computer or monitor or other hardware to try different cable wiring if you are not sure since it is all line level or for other reason(s)?

When mentioning and showing diagrams of connectors it is nice to know if your talking about what I will externally see on the outside of the 1902A monitor or on the inside of the monitor or on the cable since if you have the monitor and cable you are making in front of you both facing you right turns to left and vice a versa when you go to turn the cable around to plug it in for example when you face me my right side is to your left side until I turn my back to your face. Commodore did not at least in one case put pin connection numbers all in numerical order so each and every pin should be numbered. On the connection that you can bolt on to the Commodore C128 I do not see anything labeled Chroma or Luminance in the diagrams is it hence the case that this would not have s video?

I believe the bolt on connector does connect to RGB however is it true that this would not be as good of quality as s video and would not be compatible with s video with out some thing to adapt the signal?

I have on my DVD players on one upscaled HDMI out which is some times the best but not necessarily true the original image and I also have and another Component out which is the 2nd best quality to true HDMI out and on my camcorder I have s video out and DV out. Please let me know what all types of connections I can use with my Commodore 1902A monitor I have been told though that s video is the best quality it can display and I do not know about compatibility with 40 column or 80 column modes please let me know about how to determine compatibility, okay??

I recall that the C128 owners manual for the round din connector wiring was not correct. Please also explain in any diagrams of connectors I am looking at the cable or outside of the monitor and if you have tried the hook up or just read about it. Commodore some times used model series numbers hence if this happened I would not be sure that all of the 1902A monitors would be wired the same way. Perhaps making 2 cables of which I could interchange the connections on or some type of signal checker would be most reliable way however if there is a signal checker that could be used what would it cost and where would I get it from and how would I use it and what would it be called? Or could a disconnection of each connection one at a time to see what it does work for example one might disconnect the audio another the chroma and the other luminance if it does not harm anything however if it disconnect I disconnect a common ground would this be disconnecting all signals through this cable?. Commodore use to have authorized RCA dealers fro service centers are there any of them around that still deal with Commodore? Also Sams Photo facts is now letting at least one library make available Sam’s Photofacts manuals on the web that perhaps would help if you can download such.

Is there a way at this top reply to private email and public forum both at the same time or send a link to my private email to the public forum and if yes how sine if I get notice at my email that is the most dependable way to get in contact with me. Since I get to many forums to go to get time to check and recheck t them all out otherwise and if yes how?

Correction per C128 manula 40 column mode is v ia round DEIN connector

Correction per C128 manula 40 column mode is v ia round DEIN connector

Correction per C128 manual 2nd edition 40 column mode is via round DIN connector and my testing my C128 computer out confirmed this. I been able to get in to both 80 and 40 column modes though was not able to get the 64 mode to work in the 80 column mode though could get the 64 mode to work in the 40 column mode. On the C128 computer is it possible to get it to work in both 80 column mode and 64 mode at the same time and if yes how??
On the Commodore model 1902A monitor when it is in 80 column mode is it only one color you can get? If yes what is that color? How many colors and shades of colors can one get on the Commodore 1902A monitor is 80 column mode. Does anyone know about where to get a SID chip to add stereo sound to a 64/ 128 computers and how to install it??

The C128 has a key on the top row named 40/80. It only works in C128 mode.

In order to understand why, you need to know the C128 has two video chips: the VIC-II which produces 40 column colour graphics (same chip as in the C64) and the VDC which produces 80 column colour text/graphics. The round DIN connector goes to the VIC-II chip while the DB9 RGBI connector goes to the VDC chip. When you press the 40/80 key, you redirect text output to the VDC chip and thus need a compatible monitor connected to the DB9 output to get any video display. Technically I believe both chips are active so an advanced program could address both video chips simultaneously. You would need two monitors though.

As the 1902A monitor doesn't have a RGB input, you will only be able to get a monochrome/composite 80 column output from the VDC chip. It defaults to white or grey scale, but if your monitor has e.g. a green phosphor input, you would see it as a green scale image. I can't recall if the 1902 has this mode, earlier 1802 models had.

Commodore c128 and 1902a monitor in rgb 80 column mode

Commodore c128 and 1902a monitor in rgb 80 column mode

I have a Commodore model 1902A computer monitor connected to a Commodore C128 computer. I have used it in both 40 and 80 column modes. It has a switch on the front of the monitor under the pull down panel that says RGB although I was told it does not have RGB (I suspect I was told wrong since why would it have that switch LABELD RGB and what other format would the 80 column b)? I do not have the owners manual for the Commodore 1902A yet but (I saw a web site recently that says it will be available soon. I do have a picture of both the Commodore 1902 and 1902A I can see externally difference in both the 1902 and 1902A monitors, get back to me and I will try to email you a picture of both the monitors. It is not yet clear to me if when in RGB mode if it will give me only one color or both. I also have the service manual for 1902A PERHAS THIS WOULD INDICTE IF IT HAS MORE THEN ONE COLORM IF SOMEONE KNOWS HOW TO INTERPET IT. I AM NOT YET SURE IF THIS WOULD BE A DIGITAL OR ANALOG INPUT AND WHAT THE OTHER CONNECTIONS ARE FOR THE C128 PUTS OUT AUDIO THOUGH THE 80 COLUMN CABLE THOUGH AS WELL AS VIDEO PER THE C128 2ND EDITION MANUAL HOWEVER WHEN I LOOK AT THE PIN LAYOUT IN THE SAME MANUAL THE WORD AUDIO IS NOT USED, THOUGH IT DOES HAVE OTHER LABEL NAMES. WHAT IS THER STANDARD FOR DVD PLAYERS AND RECORDERS THAT HAVE COMPONET OUT PUT IS IT DIGITAL OR ANALOG OR BOTH AND WHAT ABOUT NTSC AND PAL DVD PLAYERS AND RECORDERS.? I THOUGHT IT WOULD BE NICE IF I COULD GO FROM COMPONENT VIDEO TO RGB PROVIDED IF THE 1902A WOULD DISPLAY MORE THEN ONE COLOR IN RGB MODE AND FROM WEB READING ON THIS 1902A MONITOR IT MIGHT REQUIRE A SPECIAL
CABLE THAHAS THE LETTER S NOT FOR S VIDEO IN ONE OF THE FIRST LETTERS OF ITS NAME I THINK THE S MIGHT OF BEEN FOR STANT, OR A SIGNAL CONVERTER. IF ANYONE KNOWS MORE ABOUT THIS PLEASE LET ME KNOW HOW TO WIRE THIS AND WHAT ALL I NEED AND WHERE TO GET THE SUPPLIES AT AND WHAT ALL THEN SUPPLIES ARE CALLED. IF YOU HAVE OR CAN TELL ME HOW TO MAKE A 80 COLUMN 128 MODE RGB SOFTWRAE PROGRAM I COULD TRY WITH MORE THEN ONE COLOR AND FOR A 1571
5.25” DRIVE I COULD TRY THAT IS WORKING THAT WOULD LIKELY BE THE EASIEST WAY TO DETERMINE THIS I WOULD CONSDIER BUYING SUCH A PROGRAM DEPENDING ON THE PRICE TO TEST THIS OUT WITH.

Do you have the ability to post a reasonably detailed picture of the back side on your monitor? I know Commodore monitors tend to be a mess when it comes to which model has which inputs. Sometimes one model number can come in many different variations based on which subcontractor Commodore bought the monitors from. Yes, those monitors usually were manufactured by other companies and then Commodore slapped their logotype onto them.

Here are some pinouts from the 1084 series monitors that may or may not apply to your 1902A monitor:

Digital RGB, 8-pin DIN: http://pinouts.ru/Video/C1084d_pinout.shtml
Analog RGB, 6-pin DIN: http://pinouts.ru/Video/C1084a_pinout.shtml (probably not, since you already have a 6-pin DIN for other inputs)
Analog/Digital RGB, 9-pin DSUB: http://pinouts.ru/Video/C1084dd_pinout.shtml (compare to the C128 RGBI output)

Your posts were hard enough to read before you switched to all-caps...

If you want more people to read them, what exactly is/are your question(s)? Preferably one at a time and in 20 words or less... ;-)

I can take a photograph however I think I can find a diagram of the connections

I can take a photograph however I think I can find a diagram of the connections

I can take a photograph however I think I can find a diagram of the connections of the Commodore 1902A monitor that would be easier see since they will not show up very will, as per an others comment I some time use all capitals since it is easier for me to read form the distance. Some people prefer all capitals and some do not I hence can not please everyone. The length I leave depends on how much information is needed. I will see if I can find a URL of the pin outs to leave here later on. where did you get the diagram of the monitors you left it mentions a analog connector. On the 1902A some people have modified them to accept a different type of signal I forget if they modified which connection for what exactly though they changed rather it would work with analog or digital on one of the connections. Rather or not mine changed I do not know since I got after some else had owned it.

How to convert a C ommodore 1902A monitor from digital to analog on its RGB article

How to convert a C ommodore 1902A monitor from digital to analog on its RGB article

How to convert a Commodore 1902A monitor from digital to analog on its RGB article, note I do not know if the belkow is correct or not andf this is an article I got from user name of MonitorGuru


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How-To: Modify Commodore 1902A to accept CGA Analog RGB
« on: October 26, 2004, 03:06:38 PM »

--------------------------------------------------------------------------------
I posted this about 2 years ago on usenet, and realized it might be better appreciated/useful here.

This is NOT a hack like others posted that are very dangerous (like directly wiring inputs into the guns on the neckboard). It really is less dangerous than a cap kit, and when the instructions are followed, you will end up with a good source for a really nice Arcade Monitor replacement (and one that is totally encased and has it's own isolation built in, so great for bench work--no open frame and no need to drag a heavy iso xformer with!)

Here's the original post:

-----------------------------------------------------------------------------

Yes, it *IS* possible to convert a Philips/Magnavox made Commodore
1902A to accept ANALOG RGB instead of DIGITAL RGB.

It's well known that the 1902 (non "A") model, the one with rounded
face and corners instead of square either directly supports Analog by
hacking the case to expose the 3rd position of the RGB switch, or that
and adding a handful of components missing on some boards.

Though I searched Google/Usenet high and low, not finding anything
[other than for the original 1902], it IS possible to modify the 1902A
series (and presumably its cousins in the Magnavox line) to accept
analog RGB for use by either an Amiga computer or arcade game boards!

The procedure:

0a) I take NO responsibility if you do not know what you are doing and
proceede to shock, maim and/or kill yourself, or any equipment you may
choose to attach to this modification.

0b) I have tested this out to ensure it is safe to connect to these
points are they ARE isolated, they are not part of a "HOT" chassis.
It's totally safe to touch these points and connect them, if done
correctly.

1) Open your 1902A. Remove the 2 screws recessed at the top back, and
2 on the bottom back, slide the cover off partway.

2) Disconnect the speaker from the connector inside, finish removing
the cover.

3) Desolder the back edge of the shield ground. Be careful--use a hot
enough iron (more than 35 watts) and don't tug, you may end up ripping
off some of the ground traces like I did.

4) Bend the shield back.

5) Locate on the top of the board the vertical riser card. This card
has a couple 74LS04 chips on it and a load of resistors. This is the
digital to analog converter board.

6) Towards the back of the monitor where the card attaches, there is a
pin labeled +5V. Locate the pin on top, then find it on the bottom
side.

7) Using a sharp knife, scrape OFF the trace just before it connects
to the pin on the card going thru the main board. We want to depower
the card, we no longer need it for analog. Test that there is no
continuity with an ohmmeter. We cannot have any voltage running into
that pin.

Looking on the top again, towards the front of the monitor the card
connects with 3 pins labeled R, G, B. They are NOT the set of 4 pins
labeled RGBI that were closer to the back and the +5 pin you just cut
the trace on.

9) Locate the front 3 connectors and solder RED/GREEN/BLUE wires to
these 3 points on the bottom. This is the RGB Analog out from the
converter card that we have just disabled. This is where you will feed
in your own analog RGB

10) Locate the left 8-PIN din connector on the left back edge.

11) Locate pin 6. It is down and to the left of pin 1, and down and to
the right of pin 4. Solder a BLACK wire here. This is VIDEO GROUND.

12) On the same connector, locate pin 8. It's the lowest pin in the
group. Follow the trace down til it ends. Solder a YELLOW wire here.
This is VERTICAL SYNC.

13) One the same connector, locate pin 7. It's down and to the left of
5 and directly left of 2. Follow the trace down til it ends. Solder a
BROWN wire here. This is HORIZONTAL SYNC.

14) Wrap the wires up and lead them out from under the metal shield.

15) Resolder the metal shield on the bottom.

16) Run the wires out the back around the power cord and up.

17) Reconnect the speaker in the back case and reattach the case with
4 screws after aligning the board when closing it up.

You are now done with the modification. If you used the wire colors I
suggested above, your wire connections are as follows:

RED/GREEN/BLUE: Analog RGB signal wires
BLACK: Video Ground
YELLOW: Vertical Sync
BROWN: Horizontal Sync.

Note: If connecting to something like an arcade game board that only
outputs composite sync, you can simply tie together the brown and
yellow wires and attach to the composite sync lead. Nothing special
(usually) needs to be done.


Also note: You may need to place a hex inverter (7404) inline with the
sync (and/or video) signals if your video source doesn't have the same
positive/negative signals as the monitor expects. Diagram here:

1 - U - 8
2 - x - 9
3 - x - 10
4 - x - 11
5 - x - 12
6 - x - 13
7 - x - 14

Pin 1: Sync from video source
Pin 2: Sync out to monitor
Pin 7: Ground
Pin 8: VCC (+5 volts DC)

Use pin pairs 3/4, 5/6, 9/10, 11/12, 13/14 if you need to invert any
other lines such as RGB. The odd # is the input, the even # is the
output.



Final Note: You may find that your signal is very strong and you have
to turn down the brightness and contrast and still not get an exact
picture. I am working on solving this problem yet. It may be as easy
as adjusting the DRIVE or CUTOFF or SCREEN controls.

The original daughter board seemed to output 1.0 volts on the analog
outs, so that may be the range it's expecting.

-----------------------------------------------------------------------------

End of original post.

Note: This hack works best with computer outputs of around .7 volts (e.g. Advance Mame or ArcadeVGA) since it wanted 1.0 volts. Arcade boards output 4-5 volts so that's why there was so much brightness noted above.

Do you need analog RGB for the DVD player?

If you need to go in the other direction, from 3-5V TTL to 0.7V analog levels, it is possible to use resistors to create voltage dividers inside the video cable. I have built two such cables for my BBC Micros, one ending in a DB9 to connect to my 1084S and the other cable ending with an European SCART connector.

Umm, I may not understand the original question, but the C-128's 80-column mode used digital RGB (RGBI) and so did the 1902A, so the C-128 and the 1902A will work together without modification. The 1902A was a color monitor, and the C-128's 80-column display could do 16 colors.

You can test the color output without a program. Just hit CTRL-1 and type a few characters, then CTRL-2 and type, CTRL-3 and type a few characters, and so on. CTRL-1 through CTRL-8 and Commodore-1 through Commodore-8 sequenced through the 16 colors. The color legends are printed on the front of the number keys if you need them.