Programs for generating old school sounds

Since I’ve started playing around with writing games again, I’ve been interested in old school sounds. These things can be hard to come by these days since a lot of the older sounds were pure square and triangle waves.

I found a couple of programs for creating these sounds. Both are windows programs
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SUBSYNTH.ZIP
SFXR.ZIP

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So far, they seem to work OK. I’m just keeping them here in case they disappear someday.

Wrote a little game… Astrosmasher

Well, out of boredom I’ve created a little game called Astrosmasher. Nothing special really, I just wanted to see if I could make a game look like an old Atari game. I think I succeeded in some ways

Astrosmasher is a partial clone of an older colecovision game bit I got bored with it pretty quickly, I think I’d like to write games that are a little more fun despite the fact that I have no artistic ability. 🙂

Anyways, here are some screen shots and a like to the game. The game requires windows 2000+.


*****DOWNLOAD ASTROSMASHER*****

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asmash3
asmash2
asmash1

Consider this game, for the most part, incomplete. I got bored with the idea and made it workable. It is a hard game though. My high score thus far is 35100. Give ‘er a shot. 😀

Temperature and light, several days

Well, It’s been a number of days since I built the unit and all’s been tested. Here is a picture of some of the data from my living room over the past several days. The purplish is the temperature and the lighter one is the ambient light. You can see that as the light levels get higher, the furnace stops, thus the temperature stops fluctuating.


The living room temperature as seen over 6 days
The living room temperature as seen over 6 days

Sorry about the small scale of the temperature graph, the graphing program is still a work in progress.

Temperature and ambient light tracking

So, since I’m really bored I decided to build a device that tracks ambient temperature and light levels. While this may not seem very interesting, I suspect the relationship between the two, while not directly linked, will be interesting especially when placed outside. Well, I suppose I’ll put a few pictures up and outline some of the stages I went through to get it to this point.

1. Prototyping.


The initial version of the sensor, using older stuff from viscometer project.
The initial version of the sensor, using older stuff from viscometer project.

This didn’t take long. I already had a board with a single supply opamp (JRC 7014D) on it that was already set up for the LM335Z temperature sensor. I used a bread board, as can be seen in the picture, and used a messy bunch of wires coming from the PICKIT2 to the MCU. I chose a PIC16F684 for this job since it has some analog channels and it doesn’t have too many pins.

2. Checking it out. In order to see if the Voltage range will allow for freezing temperatures and room temperature, I had to test it with some snow.


Cup o' snow to check and see if the Opamp is biased correctly
Cup o' snow to check and see if the Opamp is biased correctly

Temperature check with the IR gage
Temperature check with the IR gage

The voltages swung just fine with a bit of extra range. I have about 50C to work with in range, good enough.

3. Making the board. For this I used a board from measurexplorer. I have tons of these but haven’t had much luck using them. The only ones that have worked well for me are the ones with 3 holes per pad. Anyways, here are some pictures.

Start of prototyping the board
Start of prototyping the board
Finished Sensor board with both light sensing and temperature sensing
Finished Sensor board with both light sensing and temperature sensing

Anyways, This board took me a couple hours to make but it works well and required no rework, thankfully. You can see both the LM335X (TO-92) and the CDS for sensing the light. This board interfaces to an RS232 board that I’ve made and that I use for some of my other projects.

4. Getting ‘er running. While the unit itself is already programmed in terms of the MCU. it needs some adjusting for voltage on the pot and that’s about it. now to affix it to something so it doesn’t move around.


RS232 and Sensors glued to a board
RS232 and Sensors glued to a board
Tracking it on the computer
Tracking it on the computer

As you can see, I simply used hot glue to affix both the RS232 board and the sensor board to the block of wood. Its a temporary arrangement while I come up with a good enclosure for outside. I brought my old laptop out into service for this project, works well just for collecting data.

Anyways, here are some images of some collected data.


Living room temperatures (click to see description)
Living room temperatures (click to see description)

Basement (click to see description)
Basement (click to see description)

Well, so far so good. Now I’ll make the enclosure for outside and improve the sampling. hopefully I can leave it out all spring/summer and see the patterns.

Making a conductive adhesive

Well, I was trying to solder some extra thick peizo material, having very little luck when I realized that this could be solved very easily with some sort of conductive adhesive. So I set out to make some. I’m posting the steps for making a conductive adhesive for posterity and in case anyone needs to know. It’s not difficult though I have tried a few different methods and this one is the best.

1. Find your glue, preferably one that requires drying or curing, not anaerobic adhesives like Loctite (cyanoacrylate). I tried a couple of versions of Loctite and found that the conductive medium would merely clump together, making an oatmeal-glue. You can use adhesives like Rubber cement, 2 part epoxy or even white glue (polyvinyl acetate).

In this case I used two-part epoxy. It has a long cure time and its fairly rigid.


A small sample of the epoxy
A small sample of the epoxy


Nothing much to see there, since I wanted to use only a few drops of actual adhesive, I only mixed a gram or so of the stuff.

2. Prepare the medium. In this case I used a conductive graphite powder and iron filings. If you’re going to use iron filings, magnetize them first by letting them rub on a magnet, then force them off and into the graphite mixture. Beware that using a water based glue can make the iron filings oxidize.

Anyways, if you don’t have any graphite on hand you can crush up some pencil leads in a crucible or on something that will allow you to make the graphite as fine as possible. And in the event of not having any iron filings, like me, do what I did, grind or file down a piece of steel or an iron nail. make sure they’re magnetic.


This is the graphite/iron mixture
This is the graphite/iron mixture

Now, you may ask “Why iron, and why magnetize it?” Well, the iron provides low resistance paths through the adhesive and when you apply a magnetic field to the iron filings, they align themselves to the field, thus you can create a lower resistance path. I’ve reduced the resistance with this method by tens of KOhms based on the little I’ve done this so far, your results may vary.

3. Mix the glue and medium. Well this is a pretty simple step. The only thing you’ll many though is to add enough of the medium to make the overall adhesive almost clumpy, mixed to the point of saturation. This way you can ensure conductance.


This is the mixed version of the glue/graphite/iron filings
This is the mixed version of the glue/graphite/iron filings

4. Application of the glue. Simply apply the glue however you want, wherever you want. You’ll get less resistance if you place the two conductors as close to each other as possible though. Also, you’ll want to place one or two magnets, polarity aligned to the connections zones, near the adhesive. This will make the iron (if you used it) move slowly into lengthwise position between the two conductors.


This is the peice of peizo material attached with epoxy.
This is the peice of peizo material attached with epoxy.

Anyways, to be honest, I’ve only tried this formula a few times and did it entirely by eye, therefore I can’t give any exact values. But, thus far it works for me. If it works or doesn’t work for anyone else, feel free to comment. 🙂

Some documentation on an LCD display

A while back I bought some lcd displays from a dude on Ebay. After I recieved them I found that I couldn’t find the appropriate documentation. Well I found some documentation so I post it here for posterity or if anyone else wants it.

ktms1201
upd7225-ap-note
s14308ej6v1ds00

These are 12 position, 7 segment displays. They may come in handy someday so I’ll try them out later.

KTMS1201 from Modulehouse
UPD7725 controller

Playing around, drawing a valve.

I was a little bored today so I decided to draw a valve. While the dimensions are entirely drawn from my head and the valve itself wouldn’t be very efficient, I like the look of gas compressor valves. It took me a couple of hours to draw but they look OK.

I didn’t tag them or describe them. There is a seat, a guard and a valve plate. I omitted the dowel pin, bolt, center nub and lock nut. I just wanted to see what it looked like in solids. 🙂