Time Wasted: Dynex Mini-DVI to Composite (TV) adaptor

I bought this thing on ebay for a few bux. Was so ready to use my TV for movies instead of the tiny LCD on my PowerBook G4 (yep, I'm running an OLD system).

Got the thing and was immediately having trouble. I'm sure you can find out all about its incompatibility with my computer online. But I was so sure it was just a timing issue. I discovered the device actually reports itself to the computer as something like "fake device." So, that's it! All I had to do was manually configure the display parameters...

Yeah, manual display configuration... strangely reminiscent of my old XFree86 days with a fixed-frequency monitor. No biggie, I've done this before. Found a couple utilities on the 'net that actually allow you to manually tune those parameters in OSX (holy crap).

I fought those params for HOURS... looked into the NTSC specification, figured out numerous methods for calculating proper values that would work with a TV that ALSO were outputtable by my vidcard...

First of all, I could never get a timing value that synced with the TV. Either I had multiple pictures, or the picture would scroll... Yeah, it's just a timing thing, I'll figure it out, right? Found a bunch of timing-parameters for NTSC that people have used to drive a TV straight from their VGA port... yeah, that's basically what this cheap adaptor is doing...

But there was something else... it was only in black and white.

Boiled down to one thing I hadn't considered... It may well be possible to use a simple circuit (like the one in this adaptor) to merge the timing signals with the video signals... but there's no way feasible to take three separate color signals and merge them into a single composite output.

Basically, it was a tremendous waste of time. I learned a bit, I suppose... but I spent at least two days fighting with that. There's a lesson here, somewhere... I need to learn to not fight to make a $3 adaptor do something it wasn't designed to do. This adaptor was NOT designed to work with this laptop... it was designed to work with ones that have that circuitry already built-in (probably in the GPU itself)... which is why the Apple adaptor that's made for this computer costs upwards of $40.

This was never an issue of "well, if Apple can do it with their adaptor, then this adaptor just needs some timing parameters, or the mac just needs to be convinced this is an Apple adaptor" it was an issue of this is a simple pass-through adaptor and the Apple one has active circuitry inside... I've run into these things plenty of times, I should have known better.

What did I learn? I don't know, actually... I guess I learned that it's possible to change timing parameters manually on MacOS just like can be done for X... that's kinda nice to know... not that I've needed to mess with that stuff for nearly a decade. I guess I learned a little bit about NTSC and composite signals... I could do to learn a little more... (how do they merge that color info, anyways?)

Actually, after writing this, there's one other possibility I hadn't thought of... I was messing with timing parameters, assuming the device was merely passively merging the colors and timing from the VGA output into a single composite output... There is a small possibility that active-circuitry I was talking about is in fact inside the mac, and all I have to do is fake the EDID information so instead of reporting "fake device" to the system, it reports the same info as the Apple adaptor would... then the drivers would recognize it and activate that circuitry. It's plausible... (Though, the driver loaded by the system *was* the TVOut driver... I dunno.)

I am sure this isn't worth all this trouble... but these sorts of challenges seem to be the only types capable of keeping my mind at bay these days. What kinds of challenges? I guess (though I'm not sure) small-scale ones that are easily shoved to the side when they don't work... can be picked up months later when I get a tiny bit of inspiration like this and need something to drown out my thoughts... This is the dilemma of the year, if not longer... what can I do with the brain I've got, the way it's been working lately? Sleep...