Valant

So I've managed to break two LCDs so far, or so I think. I'm not familiar with what constitutes as a 'broken LCD'. Let the trial begin! Exhibit 1: Notice that the first character of each row is missing a column of pixels, and it causes every fourth character to skip a line. Exhibit 2: This is the really frustrating one. I followed Jim Henry's guide to making an LCD cable. Just as he said, the wires are a little flimsy and tend to break after a few weeks. I resoldered the wires, triple checked my connections, and then I was met with this garbled mess. The LCD worked perfectly before I had repaired the wires. I bought both these LCDs a few months apart from 411techsystems. The verdict? Common errors? Irreparable? You be the jury.

Aha, I missed that too. Thank you! I will read datasheets more carefully. The maths - I recall! Vee = Vcc - 13 I read section 3.2 prior, but I misunderstood it as "Vcc-Vee", like it were some special symbol, but it really is a minus sign. Many thanks. This makes a lot more sense.

So I happened to find a cheap DMF5005N recently. I spent a few days getting it to work and it looks great. Despite what the datasheet said (or so I think it says), this is a negative contrast voltage display. Datasheet Here Notice that in section 3.1 of the datasheet that the "Recommended LCD Driving Voltage" has no negative signs anywhere! So, I assumed it needed a positive voltage for contrast. My power supply disagreed. Lo and behold, with a negative voltage, the LCD works! What gives? Is there a surefire way to determine what an LCD needs? Furthermore, I am playing around with another LCD, the DMC-50448N. Another Datasheet This datasheet, again under section 3.1, shows positive values for the voltages. But now I'm skeptical. Perhaps this one requires a negative voltage as well?

Not to worry, take all the time you need. What exactly would those infilled plates look like? Can you show us some photos? Also, can you ship to the U.S.?

I second that. Are you still doing this?

Sure, I'll share the code as soon as I can get at it. It'll be over the weekend. You seem to be on the right track with what flips on what. I was thinking about making the lights work real-time, but I ran into the problem of mapping. If you figure something out, let me know. Dimming's a tough subject. I'm not sure what I'm going to do about that yet. I do know that because my optoisolators are zero crossing they can't be used for dimming, since they can only be switched on or off when the AC voltage is at zero. To do dimming, your circuitry has to be able to switch in different parts of the wave. At least, this is what I know now.

Dude, you are absolutely awesome. Thank you so much!

D: It stinks that I missed the bulk order...

ultra, if you're not going to be doing another bulk sale, would you consider posting the eagle files for me to etch one myself?

Points taken on disclaimers guys. I know there's a lot of extremely intelligent people on this forum, but you never know who's going to read this. Perhaps they will be someone who's inexperienced or doesn't have the slightest clue of how dangerous this is. I can say personally that I've been extremely cautious- the boxes are duck taped down when being used and the area is blocked off, and I'd hope that anyone attempting this as a result of my project would do the same. I'll alter the disclaimer a little. Haha, I don't think that's such a good idea. Thank you for pointing that out - I completely forgot to talk about audio. I'm using a small radio transmitter, so everyone would either have to bring a radio with them or use the one that's in their car. A problem I've had is that on the DOUT module, there are 8 outputs and two grounds, so ten in total on each group of pins. But the network cable has only 8 contacts, so I lose a channel for each grouping - 124 in total. Currently my program doesn't compensate for this, but I'd rather get those pins back. Just a warning this time. Bright flashing lights! MLeBCPjg15c Here's another video of it in action when I was first testing it.

At last, my project is in working order. Let me share it with you all. I thought it would be interesting to use the MIDIBox as a Christmas light show controller. Normally such systems are connected to the computer through a parallel port, but I figured, why not try it with MIDI? I mean, programming the lights could be done easily in any sequencing software like Fruity Loops and could be easily used on any computer with a USB port. My setup is pretty simple- just a core and a DOUT. It doesn't even have a case yet. D: The pins of the DOUT are connected to RJ45 network outlets, so they give me seven channels and one ground. The software is pretty simple, too. A Note-On message on the first channel will cause the first output pin to go high, and a Note-Off on the first channel will bring the pin back down to zero. This gives me sixteen channels to work with, but it would be simple enough to have it done in some less non-restricting way. The next part of the system is pretty dang dangerous; it plugs directly into the wall. I often see disclaimers associated with projects like this, so here's mine: DO NOT ATTEMPT THIS UNLESS YOU KNOW WHAT YOU ARE DOING!!!! THE HIGH VOLTAGES CAN KILL YOU!!! Seek Help! Be cautious! Here's the Solid State Relay box. Six of these things are mashed together on this board. All the triacs are isolated so they could be heatsinked together. The SSRs are optically isolated from the MIDIBox so as not to destroy my precious electronics. D: I determined that the most current this particular board could hold up against was 7.8 amps, so it's fused at 7 amps. Since then, I've built another board which can handle 12 amps. Future versions will be able to handle about that much at best - 12 amps is insane enough! There's nothing too exciting about the software. I used Fruity Loops to create sequences that would flash the lights. All in all, the project was a success, and a big hit around Christmas time for the neighbors. WjoAUMpqiQI And finally, here's a diagram of the whole setup. Comments and suggestions are greatly welcomed. Even if you want to say that I'm nuts for doing this, I welcome those too! Extra special thanks to all those involved in making MIDIBox the best DIY MIDI interface out there. I couldn't have done it without it. Some ideas were pulled from http://www.computerchristmas.com

Let's hope this is the right place to be asking this... On SmashTV's shop, there's a baseboard PCB for the MB-6582 and a CS PCB. What's the difference between the two, and which does the kit include?

Point taken.

Hey guys. I put together a test cable to make sure my LCD works. It's connected to my computer's parallel port and draws 5 volts from the power supply. Suppose I want to write "ABC D" to it. The screen shows, "AABBCC DD." What could be wrong? I've double checked my wiring, and it's all where it should be... My LCD's a backlit HD44780, 16x2, 8-bit.

Thanks for the offer dude, but unfortunately I live in the US D: That relay seems like the best I've seen so far. If only it didn't come from overseas... The problem with DMX for me is that it's so darn expensive. That's why I went with DIY MIDI. Thanks for your suggestions! I'm going to look into building a box.