Isn't it about time to update the ILDA Projector Standards?

[lasermaster1977]

After going through a number of weeks of angst, which I must stress, was beautifully cured through tremendous help from Buffo and our mutual friend icemaker (thanks icemaker for suggesting the contact) I have reached a plateau of laser enlightenment or nirvana in terms of the ILDA projector standard. I wrongly assumed the 1999 standard that I downloaded for the ILDA web site years ago and still posted was something ILDA members and their products or compatible products sought to comply with.

If most people and products of the ILDA consortium are not following the 1999 laser color intensity standard by using differential balanced line drivers to the projector then it would follow the standard should reflect the industry accepted norms, or at the very least include accepted alternatives that are also part of the standard, including publishing this on the IDLA web site and in the PDF document.

My efforts related to taking my old Apple IIe single DAC card and blanking lines which was always used as a single-ended output solution to interface with the rest of the single-ended control consoles, AOM's and scan drivers, and building an ILDA projector interface. It also but my mind thinking about doing a similar thing to interface my later, more advanced time-based 4 channel DAC co-processor Apple IIe system with 32 programmable on/off control lines (named LaserMaster) to one or more ILDA projectors. I spent months designing and fabricated an ILDA interface board and mini-console based on the written standard. Fortunately, the circuit boards are still viable for the intended purpose with the unnecessary parts removed.

Now that I don't have to use balanced lines for color intensity my parts count went down from 79 to 44, a huge savings when applied to either DAC system I have from yore. I'm thrilled!

Icemaker, things are moving much faster now!

And thanks to the other forum members for their thoughts and ideas from my other posts. You are all a great bunch of guys.

[mixedgas]

They have been updated for digital transport. I have a pair of IDN, Ilda Digital Network, boxes... There is an active ILDA technical committee right now.
If you read the last version of "1999" closely, the recommended receiver circuit has a single ended/differential switch and covers single ended color.

Steve

[lasermaster1977]

They have been updated for digital transport. I have a pair of IDN, Ilda Digital Network, boxes... There is an active ILDA technical committee right now.
If you read the last version of "1999" closely, the recommended receiver circuit has a single ended/differential switch and covers single ended color.

Steve

Thank you Steve. I have ILDA_ISP99_rev002.pdf (28 pages in length) and see no mention of recommended receiver circuit and switch to change between unipolar, single-ended RGB drive circuits and RGB differential, balanced line drive circuits. I scanned for the word "switch" and the only result I find is in the Color Channel Usage Chart section on page 16 for selecting between three or more than three color channels. Yes, technically a differential signal can be unipolar, but... In fairness, the RGB intensity spec states an intensity signal is unipolar, (I know the difference between unipolar and bipolar and both can be transmitted and recovered over a balanced line) but then goes on to infer it's output is differential as supported in the DB-25 "required signals" +2.5 and -2.5 referenced to ground. I scanned for the words "single ended" and "single-ended" and find only one search result defining the term in the Glossary.

So all my comments are in reference to this one document, and if their is an approved single-ended, unipolar exception to the defined color intensity signal attributes on pins 5, 6, 7, 18, 19 and 20 of an ILDA DB-25 connector it seems like it needs to be so clarified on pages 7, 8, 9 and 10.


I'll have to research IDN boxes as this is totally new to me.

[mixedgas]

It is in the recommended schematics , and in the signal level text as "Single Ended". It never mentions the hardware switch specifically. The committee just assumes your engineer knows how to read schematics. Where a switch is shown. Basically made it "Company Practice " back in the day, to choose single or differential. That or they forgot the switch in between Beers during the write-up.
~
They cleaned up the signaling language in 2004..

~
new stuff:
http://www.ilda.com/technical.htm
`


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Basically everything ILDA today is just do as "Pangolin Does" when it comes to signals on the DB25.
~
My copy of all three older "1999" texts is a sticky at the top of the page in Laser Displays, Shows and Scanning.
https://photonlexicon.com/forums/sho...ILDA-STANDARDS

~
Remember until L Michael Roberts and others decided that ready made, IBM-PC printer cables and IBM Compatible parallel port printer switches were the Cat's Meow, the 37 pin CPC-7 was going to be the connector. When going to a db25, some pins were discarded. I actually have a 37 Pin ILDA Cable in my collection. But the DB25 became the de-facto standard.
~
Please see attached, note yellow circle around "2X" switch on single ended receiver..



Steve

[colouredmirrorball]

I think the focus now is to shift away from describing how a projector should respond to analog signals and instead move into the digital domain. It no longer matters how you get the signals across, as long as the system can accurately reproduce what is meant by the artwork.

IDN is a network protocol (Ilda over Digital Network). It allows transfer of laser projector signals (X, Y, colour, blanking, shutter, status, even DMX and custom signals) between compatible network devices, in particular projectors which need to be connected to a local network.

[lasermaster1977]

It is in the recommended schematics , and in the signal level text as "Single Ended". It never mentions the hardware switch specifically. The committee just assumes your engineer knows how to read schematics. Where a switch is shown. Basically made it "Company Practice " back in the day, to choose single or differential. That or they forgot the switch in between Beers during the write-up.

So, the reason for confusion is revealing itself.

The schematic you have included in this thread is not in the ISP99 document but (my BAD that I missed your note on page two of the "ILDA-CONNECTOR1.PDF" document and the schematic which appears at the veeeery end. (I did read this but since it appeared to be the same information contained in the ISP99 document I never scrutinized it to the end to see the all important schematic. I've seen posts of yours showing the top half of this schematic page, but unfortunately I never saw this whole page in forum posts I've come across.

Hopefully my point may inspire consolidations of ILDA standards if they are intended to propagate into the future, however, it would be most helpful for those wanting to see and learn ILDA's accepted standards and practices found in one and only one current ISP document with all pertinent information.

Basically everything ILDA today is just do as "Pangolin Does" when it comes to signals on the DB25.

I see that now, as for the first time last night, to confirm what I just learned on single-end intensity signals being the norm now, I put my scope on pins from a breakout cable tying my FB3QS to an ILDA compliant Chinese projector. R-, G- and B- pins are at power supply ground.

Remember until L Michael Roberts and others decided that ready made, IBM-PC printer cables and IBM Compatible parallel port printer switches were the Cat's Meow, the 37 pin CPC-7 was going to be the connector. When going to a db25, some pins were discarded. I actually have a 37 Pin ILDA Cable in my collection. But the DB25 became the de-facto standard.

There again, I've seen products with a connector like this but for all the ILDA standards documents never seen mention of the 37 pin CPC-7. So where is the pin-out standard for this connector?

For years I've had and read the "ILDA IDN-Stream_rev001 document", just as an FYI. And I assumed these were the standards that DACs like EtherDream2 complied with, correct?

Thanks Steve and coloredmirrorball!

[colouredmirrorball]

For years I've had and read the "ILDA IDN-Stream_rev001 document", just as an FYI. And I assumed these were the standards that DACs like EtherDream2 complied with, correct?

Unfortunately not. Etherdream uses its own network protocol that its driver uses to communicate with it, which is open source. If its architecture allows it, J4cbo could update the firmware so the DAC accepts IDN streams in addition to etherdream streams but this is not planned as far as I know. Other manufacturers, such as Pangolin, Fiesta, what have you, use a proprietary closed source protocol.

Instead of having a standalone DAC with an Ilda cable, recent developments (well... it's been going on for longer than a decade now) caused more and more projectors to ditch the Ilda connector in favor of a RJ45 connector with built-in DAC. These network protocols usually being closed source, this trend means that projectors will no longer be compatible with any DAC as they used to be with the standard DB25 connectors. That's the philosophy behind IDN: make an open protocol that projector manufacturers can adopt in favor of closed locked-in formats.

[JohnYayas]

They have been updated for digital transport. I have a pair of IDN, Ilda Digital Network, boxes... There is an active ILDA technical committee right now.
If you read the last version of "1999" closely, the recommended receiver circuit has a single ended/differential switch and covers single ended color.

Steve

Were you ever able to review the IDN stuff? I remember you posted that you planned to do that some time ago when they were announced by Dirk.

[icecruncher]

I'm glad buffo and you got together.

And nice to hear it,

ILDA Nirvana huh?

Well, can't wait to join you in Laser Nirvana and I hope as a newb, I continue to learn from guys like you and buffo.

Buffo is right though, you ought to come and check out SELEM sometime. You would be impressed1

After going through a number of weeks of angst, which I must stress, was beautifully cured through tremendous help from Buffo and our mutual friend icemaker (thanks icemaker for suggesting the contact) I have reached a plateau of laser enlightenment or nirvana in terms of the ILDA projector standard. I wrongly assumed the 1999 standard that I downloaded for the ILDA web site years ago and still posted was something ILDA members and their products or compatible products sought to comply with.

If most people and products of the ILDA consortium are not following the 1999 laser color intensity standard by using differential balanced line drivers to the projector then it would follow the standard should reflect the industry accepted norms, or at the very least include accepted alternatives that are also part of the standard, including publishing this on the IDLA web site and in the PDF document.

My efforts related to taking my old Apple IIe single DAC card and blanking lines which was always used as a single-ended output solution to interface with the rest of the single-ended control consoles, AOM's and scan drivers, and building an ILDA projector interface. It also but my mind thinking about doing a similar thing to interface my later, more advanced time-based 4 channel DAC co-processor Apple IIe system with 32 programmable on/off control lines (named LaserMaster) to one or more ILDA projectors. I spent months designing and fabricated an ILDA interface board and mini-console based on the written standard. Fortunately, the circuit boards are still viable for the intended purpose with the unnecessary parts removed.

Now that I don't have to use balanced lines for color intensity my parts count went down from 79 to 44, a huge savings when applied to either DAC system I have from yore. I'm thrilled!

Icemaker, things are moving much faster now!

And thanks to the other forum members for their thoughts and ideas from my other posts. You are all a great bunch of guys.

[mixedgas]

CPC--37

http://www.ilda.com/resources/Standa...1-Aug-1989.pdf

A major advantage was a data stream option and two scan heads. I like CPC connectors, and use them for other tasks.

Steve