9 pin ??? to 15 pin vga

[Stone]

As others have mentioned, there are specific models of multi-sync VGA monitors that can do it, although not all monitors categorized as multi-sync can.

I have a NEC Multisync, MODEL # JC-1401P, the original NEC Multisync that does that. I've got an extra one in excellent working condition, with the 9-15 pin adapter if anyone's looking for one.

 

[Xacalite]

BTW, can somebody recommend some MDA->VGA signal converter?
Some Gonbes thing, perhaps?

 

[ropersonline]

Some more googling revealed that your VM-3 is a 4:3 landscape monitor, and its pinout matches the standard TTL mono monitor pinout, and moreover, I think the specified 900x700 resolution and given scan frequencies mean that it's a bog standard MDA/Hercules-compatible monitor (i.e. 720x350 or 348px), because the 900 is probably a theoretical CRT maximum, where in practice there are 90px-wide margins on each side in MDA/Herc mode, and 700 = 2 x 350.
http://support.radioshack.com/support_accessories/4687.htm
You could buy some MDA/Hercules monitor and hook that up to fix that system, and worry about fixing the (possibly) moulded mutilated monitor cable later. (Measuring video adapter output would be a lot easier than identifying input wires.)
However, cost and luck are factors: New MDA/TTL-compatible monitors are deemed "special" hardware that's sold typically with a hefty pricetag to industrial users who still depend on this stuff. Scoring a much cheaper working MDA/TTL-compatible monitor can be a bit of a crapshoot. Sometimes they're offered for pennies on the dollar, sometimes not at all. But, I've just seen Stone's offer. It could well be a good one.

If not, looking at the PCB in the monitor might give you some clues which pin is which... but even that is probably not necessary. It should be easy enough to figure out which is ground, and after that you only have a few different combinations to guess at as to which is H, V, Vid, and Vid Intensity.

Could you elaborate? Is there a procedure you have for this? What would you do, exactly? I'd especially like to know if there's any risk of releasing the magic blue smoke when randomly trying permutations.

 

[vwestlife]

If you come across one, a Mitsubishi AUM-1381 Diamond Scan monitor works fine with MDA/Hercules video. Just switch it into TTL mode and use a straight-through 9-pin cable, same as with the older NEC MultiSync monitors.

Some Brother word processors also used an MDA-spec monochrome monitor. Sometimes you can find those at thrift stores, garage sales, and such.

 

[ropersonline]

Even the IBM PGC in 1984 used something very similar to the 9-pin VGA pinout, only difference being one composite sync instead of H/V sync on separate pins. Most late VGA monitors will do OK with composite sync as well

Hm, do people think a shared RGB-return = ground = shield configuration is safe to try?
Because if both that and your composite sync suggestion work, then I think I've just found a new obscenity to try out: Feeding VGA through USB cables.

Instead of USB's +5VDC, data-, data+, GND, and shield, I could try R, B, G, comp-sync, and shield=GND=ret.

Am I taking crazy pills? Would this be reasonably safe to try?

 

[SomeGuy]

Could you elaborate? Is there a procedure you have for this? What would you do, exactly? I'd especially like to know if there's any risk of releasing the magic blue smoke when randomly trying permutations.

This risk of letting smoke out is minimal, although I would probably find a way to do that.

It does rely on the computer starting up and putting out the correct video signal with some content.

I'd start with simply using a voltmeter to find the ground by testing between any ground plane on the monitor and the wires.

To be on the safe side, it would probably also be a good idea to verify the ground pin and output voltages on the video card.

After that I would find the H and V signals. With the brightness and contrast turned up you should see a dim raster in the background once those are connected correctly. If the monitor starts acting too "unhappy" just remove the connections immediately.

Then it should be easy to find which one is the normal video. The intensity output usually doesn't output anything unless their is "highlighted" text on the screen. Getting those two backwards would result in some text not being visible.

 

[ropersonline]

This risk of letting smoke out is minimal, although I would probably find a way to do that.

It does rely on the computer starting up and putting out the correct video signal with some content.

I'd start with simply using a voltmeter to find the ground by testing between any ground plane on the monitor and the wires.

To be on the safe side, it would probably also be a good idea to verify the ground pin and output voltages on the video card.

After that I would find the H and V signals. With the brightness and contrast turned up you should see a dim raster in the background once those are connected correctly. If the monitor starts acting too "unhappy" just remove the connections immediately.

Then it should be easy to find which one is the normal video. The intensity output usually doesn't output anything unless their is "highlighted" text on the screen. Getting those two backwards would result in some text not being visible.

Let's see: After GND is correctly connected, there'd be four choices as to which pin is Hsync, and then for each of those, there'd be three Vsync choices. That's 12 permutations, right?
But maybe we can do better:
Per mentioned that many VGA monitors accept composite sync, which I understood to mean simply Hsync and Vsync combined (not sync on green in this case). Correct me if mistaken, but (with a look at the pin out box here), I understood composite sync to mean H tied to V = both connected to pin 13 on the monitor's DE-15 connector instead of V connected separately to pin 14.
Would it be reasonable to expect that MDA/Herc/TTL monitors might also at least tolerate composite sync without going too crazy? So (with a look at the MDA pinout here), would it be a good idea to tie 8 and 9 together and go find H on the monitor with that? (Four choices.) And to then try and find the V only after some "we're getting there" has been observed on the monitor? (Three choices.)

Is this a bad idea or an actually useful one?

Or, would it be better to maybe try just (non-composite) Hsync first, and then try Vsync? Roughly what should one expect to see with V floating but H correctly connected?

 

[per]

Hm, do people think a shared RGB-return = ground = shield configuration is safe to try?
Because if both that and your composite sync suggestion work, then I think I've just found a new obscenity to try out: Feeding VGA through USB cables.

Instead of USB's +5VDC, data-, data+, GND, and shield, I could try R, B, G, comp-sync, and shield=GND=ret.

Am I taking crazy pills? Would this be reasonably safe to try?

It might just work, but bear in mind that VGA has a cable imedance of 75 Ohm while USB have 90 Ohm cable impedance. It won't do damage since the video signals are quite low-power, but you might experience some ghosing.

 

[Chuck(G)]

I have a NEC Multisync, MODEL # JC-1401P, the original NEC Multisync that does that. I've got an extra one in excellent working condition, with the 9-15 pin adapter if anyone's looking for one.

My old NEC Multiscan had a DE-9 connector and could sync from CGA to VGA frequencies to 800x600, analog or digital. My Mitsubishi Diamondscan will similarly do that--and includes composite sync as well as SOG as well. It has several connectors on the rear, including BNC, DB-25 and DE-9.

 

[ropersonline]

My Mitsubishi Diamondscan ... has several connectors on the rear, including ... DB-25

Is that a serial (or printer?) port to do with built-in terminal functionality, or is this some exotic video connector? If it's the latter, do you know what it's called or have a pinout?

 

[vwestlife]

Is that a serial (or printer?) port to do with built-in terminal functionality, or is this some exotic video connector? If it's the latter, do you know what it's called or have a pinout?

The DB25 is for video:

1 Sync. GND
2 Red video
3 Red video GND
4 Green video
5 Green video GND
6 Superimpose control (YS)
7 Superimpose GND
8 Video input select (AV)
9 Comp. video in
10 Comp. video in GND
11 Comp. video out
12 Comp. video out GND
13 PGA mode control
14 Blue video
15 Blue video GND
16 Horizontal Sync./Comp
17 Vertical Sync.
18 NC
19 NC
20 NC
21 INT
22 Comp./RGB select
23 Analog/TTL select
24 Remote
25 GND (shield)

 

[Chuck(G)]

Make that the Sony Multiscan. But the DB25 on the Mitsubishi is just another video input. I think (but haven't checked) that I've got the AUM 1381A. It really is a jack-of-all-trades.

 

[ropersonline]

The DB25 is for video:
(...)

Thank you! So DB-25 can also be video. TIL. Is that DB-25 on the monitor male of female? Do you know what that connector is called?

 

[vwestlife]

Thank you! So DB-25 can also be video. TIL. Is that DB-25 on the monitor male of female? Do you know what that connector is called?

All of the video connectors on the back of the monitor are female.

I was lucky to get mine with the matching DB25-to-VGA cable. I'd imagine such a thing would be nearly impossible to find today.

 

[ropersonline]

All of the video connectors on the back of the monitor are female.

I was lucky to get mine with the matching DB25-to-VGA cable. I'd imagine such a thing would be nearly impossible to find today.

Oh, you know what? Maybe that DB-25 on the OP's SBC is also the same kind of video connector.
(Unlikely, but not impossible. I can't tell from the OP's picture whether that DB-25 is male of female.)

 

[Stone]

I was lucky to get mine with the matching DB25-to-VGA cable. I'd imagine such a thing would be nearly impossible to find today.

But not so hard to cobble together. I have lots of 9 -15 pin VGA adapters for use with multisyncs. Combined with a 25 - 9 pin modem cable you should be in business in no time.

 

[zeos]

the unit is a geometrics es2401 seismograph. Here is an ebay ad I found with some picture of the unit in one piece. The one in the ebay ad has what looks like a tape drive where my customer's unit has a hdd. Based on the instructions in the manual I was given today the other card is some kind of ram disk and that is why it has to be re-setup when the batteries on that card go out. The customer also dropped off the manual and a boot disk necessary to setup the system, so hopefully the manual will provide some more information about the system in general.





in response to ropersonline

1. yes, there are two 9pin video ports, based on the magazine ad that was posted I think we can say with some confidence that the 34010 "video card" is in fact a video card. there is also a 9pin on the sbc that is labeled "ext monitor."

2. I only have the customer's say so on whether or not they used that monitor, and he said that is the monitor they use with it. I have never seen this unit in operation so I only have my customer's info to go on.

3. there is no connector on the back of the monitor just a cable coming out of the monitor shell. my second question, in the original post, on a separate line, containing only that question, mentions the monitor and 5 wires. I fail to see the suddenness or ambiguity in that question.

5. My hope was that I could just wire up a cable to use with a regular vga monitor. failing that I would have to make the old monitor work.

6. the board says "34010 monochrome rev. 2a pc tech, inc lake city, mn". the monitor looks 4:3/landscape to me.

(commas, periods, and question marks are not punctuation; color me surprised¿!.?¡)

8. the other connector on the sbc is for the builtin printer. it already has a ribbon cable attached and is labeled as such. there is a 9pin serial port, but there is no output on that port. the instructions in the manual say to connect the monitor to the video port.

 

[vwestlife]

But not so hard to cobble together. I have lots of 9 -15 pin VGA adapters for use with multisyncs. Combined with a 25 - 9 pin modem cable you should be in business in no time.

Not even close. The monitor's DB25 video port uses pins that 25-pin RS-232 only uses for second channel or synchronous communication, neither of which are present on 9-pin serial ports.

 

[vwestlife]

zeos, you need an MDA monochrome monitor, such as:

http://www.ebay.com/itm/331626392307

Assuming it works, that price is actually not bad, considering that it includes free shipping.

Or if you can attach a new video cable to it, there is also a chance that the Tandy monitor you have might still work.

 

[Stone]

Assuming it works, that price is actually not bad, considering that it includes free shipping

I have one that does work so there's no guesswork involved.

If you want it, let me know.