Laser Projector (Red, Green, Purple) "Laser 3D Party Light" from Spencer's

[mixedgas]

Did you get a email with a series of attachements?

If not, let me know. I'm on jury duty this week and next and my net access may be messed up.

Steve

[DogP]

Just a quick update... I made a simple test file with a bunch of closely spaced points to determine the resolution of the DAC. The answer is: 8-bits (not surprising).

Attached are pics of my cheap portable scope screen (sorry, I didn't feel like grabbing the USB cable)... It's approximately 10.8Vp-p, and each step is about 42mV, which verifies that it's 8 bits. Also, note the noise from the switcher at about 18KHz. It's noisier when it's moving faster and the lasers running... the third image is of a slow return with the lasers off.





DogP

[mixedgas]

Time to deglitch the switcher ....

Steve

[james]

I don't suppose it matters, but you can set LaserBoy to display any vector art loaded into its memory in any bit resolution you want. You do this by masking off the lower bits in menu t signal bit resolution. So you can see what it really looks like and tweak it if necessary. You can apply the resolution mask and save the art that way as well.

James.

[DogP]

So... I showed this to a friend of mine, and he had to have it. So he paid me for it, and I went and bought another. Strangely enough, it looks like they have at least two different designs. This one has a single controller board (not stacked boards like the other), with a few changes. I initially noticed the lack of extra headers... there's no LCD, button, etc. headers. I was initially disappointed by that, but after seeing the performance difference, I'm okay with it.

The lasers, galvos, and amps are identical... it's just the controller board that has changed. At first glance, it looks like the board just got a revision, but looking closer, you can see that the microcontroller has changed. This one had the top ground down to hide the marking, but with a little cleaning, light, and magnifier, I could make out the markings (with fairly high certainty). It's a LPC1114FBD48/302 ARM Cortex-M0 (32 bit micro, running at up to 50MHz), which is a big step up, assuming the other was in fact a 8051 clone (8-bit micro, and had a 12MHz crystal, though I guess it could have been running faster w/ a PLL). This one also has markings on the DAC, which is a TLC7528C (8-bit, same as before). The rest of the stuff looks pretty much like the other.

I was initially worried, because I tried SD cards that I had used in the other one, and they didn't work in this one. I thought maybe they added some protection... but it turns out that it's just really picky with SD cards (I tried 5 different ones, and only one worked). It came with the same "Elite Pro" card that the other came with... so I ordered one of that brand from ebay, which will hopefully work.

Performance wise, this blows the other one out of the water. This one can draw MUCH faster, and it looks WAY better. No more wavy lines, less noisy, and better performance. I'll let the pictures do the talking (though my ability to take good photos is still lacking ). On the other one, I could never get the blue circle in the ILDA pattern to go inside the box, but this one does (doesn't look like a perfect circle though). I didn't check drawing speed on all patterns, but on one of them, specifying 5k actually did 4.9k, 10k=9.1k, 20k=17.4k, 30k=25.6k, and 40k=33.6k. That's the speed of the actual drawing... there is also a near constant (14ms-17ms) blanking time between each frame. And at the end of the loop count specified in the .prg file, there's a small hiccup to either restart the loop (if on "pause" mode), or start the next file. As expected, the factory didn't do a great job on convergence... the green laser was noticably off, so I fixed that.

On the normal user side of things, this one is also different than the other as it doesn't appear to have internal patterns. On the other one, if you remove the SD card, it draws a long sequence of simple patterns, and the sound activated mode is also generated internally. On this one, it does nothing without an SD card, and the sound activated mode steps the frames of the current file being played from the SD card (which is way cooler, since you can design your own pattern to change with the beat). The card looks to have the same files on it, but the .prg file is slightly different.

So, if anyone plans to pick one of these up, based on my limited experience with these, I'd highly recommend looking through the side vent to determine which version they have, and get the single board one (maybe let one of the workers there know what you're doing so they don't harass you about opening boxes). An easy way to tell the difference is to look for the three connectors going to the lasers. On the good one, they're in a row along the bottom... on the other one, they're spread around the laser sub-board. A flashlight would probably help. On a side note... the PCB is taller, which makes the SD card press against the top of the case and pop out when you pull the back off. Not a big deal, but obviously a slight mechanical miscalculation on their part. I'll probably cut a hole so I can swap the card out without removing screws anyway. Oh, and on both of them, the fan hole is too small for the fan (40mm fan with a 28mm hole), so the fan basically just blows into the back wall (it's configured for exhaust). I'd recommend using a step drill bit and expand it to the correct size.



ILDA pattern @ Speed 5 (around 5K) (slow to draw, so only partly visible)


10


20


30


40


DogP

[DogP]

I received the Elite Pro SD card (2GB) from ebay, and it worked perfectly with this projector... so I'd recommend buying that brand (same brand that both projectors came with).

I also had a little fun making a mockup of a Tempest screen... turned out pretty good for a first try IMO.



DogP

[Photonbeam]

That looks cool!

[mixedgas]

Thanks for the update on the new model.

I Wonder if they set the security bits on the MPU?

Steve

[DogP]

I Wonder if they set the security bits on the MPU?

Not sure... I don't have a programming/debugger pod for the Cortex. There's probably not much useful stuff to do with the ROM even if it was unprotected anyway. I definitely like the improved performance though.

And looking at those galvo kits on ebay, I'm slightly curious what was upgraded going from the 12k to 20k driver board. This looks to have the 20k galvos with the 12k driver... just wonder if that's limiting my performance any.

And while the standalone SD interface is nice, I'm thinking it'd be nice to also be able to optionally run it from a PC, for more control (and real-time). I see it has 0.1" headers labeled Red, Green, and Blue... not sure if that's for external control, or just the MCU pins being broken out. It'd be nice to reuse the laser drive circuit without hacking the board or using a different laser driver board. The XY control would be easily switched.

DogP

[GridMonkey]

I bought the original version of this laser scanner and started a topic a while back, I'm not really a hobbiest, i was just intrigued by the idea of writing my own files. I've since managed to mess up just about everything i can as far as how to use the SD card and the image files. the .prg file and i just don't get along, i can make no sense of the parameters and i just want a functioning playback again. Is there any chance i can get a zip file with a bunch of working ild files and a prg to run them all? I backed up the SD card at some point but i have so many files and pieces of software that i don't understand that i don't even know where that backup is to place it back to factory settings. Thanks in advance

Luke