Andy's Electronics Projects

Genesis Spectrum Analyzer

2012-01-28T18:10:00.015-05:00

Built a custom interface using an ATMEGA328, an MSGEQ7 (7-band spectrum analyzer chip) and a genesis cable plugged into port 2. Sends all 7 bands with an 8-bit resolution with a 4-bit ID to make sure things are always in sync. Running the genesis side ROM on an everdrive.

Really wanted to try my hand at having an audio assisted visual set. Tried an amplitude based one but it wasn't exactly what I was looking for. The chip works really nicely, and once you adjust the threshold it finds the beat very reliably.

Debug / POC ROM - ran a frequency sweep through, works perfectly!

Actual implementation into a new ROM I've been working on. A set of lines are drawn every frame into a tilemap in RAM then DMA'd over right after vsync. Rather than overwriting the tiles under it each line has a defined weight that is added to the array. The sum corresponds to a palette entry, so the longer the effect stays on the more intense the color becomes (black->blue->purple).

Only using the 63hz band here, very effective! You can see around 1:15 where there is a constant tone the effect will play out.

Music by the amazing Danimal Cannon!

Now to (tastefully) work it into some new effects! Should have it in time for Blip Festival Australia.

Blip Australia 2012 Genesis ROM Flyer

2012-01-25T13:37:00.006-05:00

After a few months of work it's finally finished...

Code: Batsly Adams
Gfx: Wazpy
Music: Animal Style

Download the ROM here!
http://australia.blipfestival.org/files/BlipAustralia2012.bin

I got to try out a ton of new stuff here, learned a ton in the process.

A few notes:

Wrote a new scene handler, allows separate scenes that can exit gracefully regardless of changes in video modes. Scene timers can be easily adjusted.

New smooth non-blocking palette fading.

VDP DMA routines work perfectly now, most effects are applied to a tilemap in RAM then DMA'd over right after vsync. A 32x32 map finishes in vblank with time to spare, which means no more tearing!

Wrote a utility to split GIFs into frames and convert them into tiles / palettes. Have a special struct for sprites to handle this output for easy manipulation too.

The large comet is 128x128 -> 16 32x32 sprites stitched together!

The green/blue lines in the announcement scene have a (subtle) transparency effect surrounding the black bar. Used the shadow/highlight registers on the VDP here for certain tiles to simulate opacity.

And finally: a full speed plasma effect, which was the holy grail of visual coding for me. Thanks so much to Andy B for help with the optimization.

Can't wait for this!

Blip Australia 2012

2011-12-20T18:13:00.005-05:00

I'm extremely proud to announce that I'll be performing at Blip Australia 2012! I'm honored to be part of such an incredible lineup.

Check it.

7bitHero (BNE)
10k (SYD)
Abortifacient (SYD)
Batsly Adams (US)
Bit Shifter (US)
Derris-Kharlan (MEL)
Dot.AY (MEL)
_ensnare_ (UK)
Hally (JP)
iLKke (SYD)
Lazerbeat (UK)
little-scale (ADE)
Nullsleep (US)
Patric C (DE)
Saitone (JP)
Trash80 (US)

http://australia.blipfestival.org/

Workbench 11/2/11

2011-12-20T18:00:00.002-05:00

This is the cleanest it has been since it was built.

Card Preview

2011-12-20T17:58:00.004-05:00

Circuit card preview in collaboration with Jeremiah Johnson. The result of a few months of circuit design / code.

Release info will be up soon!

Fontana's I/O Sep11

2011-12-20T17:55:00.004-05:00

Wrote a new Genesis text scroller that uses the SD-card on the everdrive! The ROM takes any (8x8) bitmap font from a folder and copies it to RAM for scrolling. The string is precompiled, working on an neat interface to edit on the fly at gigs / save previous names to SRAM.

Had so much fun at that show, everyone was amazing.

PCB Design

2011-11-02T02:54:00.006-04:00

So I've been on a roll since I've setup new workspace/benches (thanks again Adam / Todd!). I decided to go through my old parts / unfinished projects to tie up some loose ends. Setup a few devboards for a PIC / attiny / propeller. Had nothing in mind, but after some playing around, I had an idea for a project. Contacted Jeremiah Johnson (www.nullsleep.com) to collaborate. The function will remain a secret until gli.tc/h but I can say that it's my favorite project to date, and I'm super proud about how it came out. Got intimate with some (frequency/amplitude/phase) modulation, learned a bunch about surface mount design and SD card interfaces too.

Designed the PCB in Altium, had a few ups and downs. The 3D renders are pretty neat and overall the experience was pleasant. Any hangups were probably due to a misunderstanding how libraries / custom parts are handled.

Ordered 20 boards, they arrived in about 10 days. Doh, botched silkscreen on the front. I think I may have overloaded their silk machine, I'd imagine those halftone dots could cause a problem since each counts as an individual shape. Luckily none of the text was affected and the back is absolutely perfect. They look amazing otherwise, excellent quality.

Fixed it up with my vinyl cutter anyway, it's temporary until rev 2, but that's okay! Looks great.

Works better than expected, can't wait to show it off!

WTPA2 DPCM Drumkit Test

2011-09-13T12:51:00.001-04:00

RB drum kit run through a USB-midi converter to the WTPA2.

I fixed a bunch of bugs with the sample code, I had the DAC return to zero immediately after the sample was done playing which caused a nasty click/pop. Now it gracefully levels out any inactive channels.

WTPA2 DPCM support

2011-08-20T12:47:00.000-04:00

WTPA2 code modified to load native NES samples (1-bit DPCM) from a uSD card. I could have converted them to wave but what's the fun in that?

Uploaded to WTPA via ISP/STK500 devkit.

128 samples taken from Bucky (explod2a03)'s DMC pack.
http://theshizz.org/forum/index.php?/topic/25657-n-e-s-sample-pack-v1/

As always, big ups to Todd Bailey (www.narrat1ve.com). If you're even remotely interested in this stuff you owe it to yourself to get a kit.

Chipocrite @ Lebowskifest

2011-06-23T11:38:00.002-04:00

did visuals for lebowskifest philly! (2 x genesis + gp2x)

chipocrite absolutely rocked the place!

FaMI VRC6 Support!

2011-04-18T13:02:00.002-04:00

Implemented VRC6 (for powerpak users) - Both square channels + sawtooth working perfectly

Channel remapping - MIDI channels can now be reassigned on the fly with a controller in P1. They can even overlap! So you can assign a single MIDI channel to multiple channels on the NES and they will play simultaneously. A detune / transpose option was added so you can create multi-channel leads if you are using this as a live instrument.

Sent out a couple of demo boards - a few bugfixes later and things are stable! It's pretty much interface / sound preference coding from here on out!

BOSTON8BIT Presents: PAX East 2011 Chiptune Showcase

2011-03-09T13:04:00.006-05:00

I'll be performing visuals on March 11-13 from 11am-2pm at PAX East in the jamspace. Stop by and check out some amazing artists / say hello!

=== FRIDAY ===
Cathode Rays
Oxygenstar
Active Knowledge
Animal Style
Bit Shifter
=== SATURDAY ===
AdamGetsAwesome
Zen Albatross
Danimal Cannon
Br1ght Pr1mate
Smiletron
=== SUNDAY ===
7th Gear
Facundo
Shortsleeves
Disasterpeace
glomag and Corset lore
=== VISUAL ARTISTS ===
InvaderBacca
HN_i_C
Batsly Adams

In da lab

2011-03-01T23:38:00.000-05:00

NSF sync x 2 WORKING

DrunkenNES

2011-02-28T23:02:00.026-05:00

Edit: If you're looking to contact me you can use (lousy spambots.)

The third in a series of new NES peripherals - I present to you...

Wow such an overwhelming response for this thing! I'll put up a video with more of the screens / music - hopefully by tomorrow.

Thanks Jessen for taking video - there is actually a lot more to the game - I'll try to find some more!

2011 Feb 26 - Drunken NES Breathalyzer - Pulsewave at The Tank, New York from EM Dash on Vimeo.

So about DrunkenNES. I had recently done a workshop for 8static and bought a bunch of sensors to show the basics of physical computing. I came across an alcohol sensor and thought it would be fun to play with. I hooked it up to a scope and showed it to a couple of friends I had over. A couple of hours later we had a ROM with the sound pitching up as it detected more alcohol - which we really couldn't stop laughing about.
I got to leverage all the previous work in the NES communications driver I had written for the Arduino (using an RBBB in an enclosure). We forced a friend to drink for science - we all did a lot of drinking for science. The thing is actually pretty accurate provided you didn't have a drink in the past 3 minutes - it was fun having excel open "collecting data".

So alcohol sensor -> ADC on Arduino -> NES communcations driver -> gameport #2 -> homebrew software on NES powerpak cart

We decided to make it a full fledged game from there - AdamGetsAwesome helped me test the circuit / wire up the cart - Kris Keyser managed to learn Famitracker and wrote a great soundtrack in a few days - and I commissioned a few artists to generate some graphics (Alex Baderian, Emi Spicer, Kathleen Wisneski). I'm still amazed everything pulled together so well. I'm actually ashamed to admit that the code is about 5 times as long as the MIDI interface (2500+ lines of 6502 assembly!) - really complex. I made great use of bankswitching with the MMC1 mapper to handle all of the nametable / music data.

Features:
* 6 states you could rank in depending on your reading:
sober / getting started / buzzed / tipsy / drunk / wasted
* Each state to have up to 4 screens with 2 frames of animation each and cycles through each every time it's hit (you should never see the same screen twice).
* Fully functional 6-digit hi-score table (saves to SRAM for battery backed scores)
To keep it fun - the score is derived from your reading - not your rank (I.E. I can have a higher "drunk" score than someone else).
* Original soundtrack (10 tracks by Kris Keyser!)

Also: the foundation of the game is based entirely on crumby animal puns - see below

FaMI Update

2011-02-14T15:42:00.003-05:00

Total revamp - almost fully MIDI compliant! Major update soon.

Sega Genesis visuals

2011-02-14T14:57:00.006-05:00

So I'm back into Genesis coding now!

Just did visuals for the amazing note! on the engadget show! Thanks for having us - it was a blast.

Schematic + Optional MIDI-in

2010-10-07T17:57:00.005-04:00

MIDI-IN portion lovingly ripped from the Arduinoboy schematic (I already had the circuit built!)

NES->PC Schematic

2010-10-01T14:04:00.002-04:00

NES-NES NSF Sync

2010-09-29T01:12:00.001-04:00

I took a break from FaMI to try out something new.

I've coded up 2 different NSF playing roms (modified versions of the amazing vegaplay - thanks to NO CARRIER) - one is a master that sends a "sync" signal and one is a slave that does nothing but wait for the rising edge of that signal. Based on the way I'm running the sync it's impossible for them to fall out of time. Right now I'm using an Arduino as a clock source (which is overkill, you can use something like a 555 timer) in place of a "master" NES but you get the picture. I don't have 2 powerpaks to test out the real deal right now, but would anyone be interested in this type of thing?

Possible uses:
- 2 NSF / 10 channel songs?
- If you use 2 slaves running from a single clock source you can play the same NSF to switch over during a live performance in case one fails

Analog control of glitchNES v0.2

2010-08-09T09:55:00.001-04:00

Korg nanocontrol + powerpak + arduino

CC01 : Delay speed (0-127)
CC02: Bank select (0-7)
CC03: Nametable select (0-7)

Song: Animal-Style - LameFAQs
www.animal-style.com

glitchNES 0.2
www.no-carrier.com

PC-NES Transfer Tool / FaMI
www.batslyadams.com

Korg nanokontroller + LogoNES

2010-08-03T00:10:00.001-04:00

Bought a KORG nanokontroller today - modified the great logoNES to take CC messages!

Things are coming together nicely.

PC->NES Transfer Tool Opcodes

2010-08-02T00:25:00.000-04:00

I'm hoping that people will develop stuff for this. You really only need to be able to program something that can write to the serial port which can be done really easily with something like processing. Everything works on 2 byte messages formatted as ([command] [value])- I've put up a list of the ones I'm using so far.

PC->NES Transfer Tool Opcode List
For instance - some pseudo code for writing a message to the screen.

String message = "Hello world!"
// Set the VRAM address to the top left of the name table (0x2000)
Serialport.write(0x01, 0x20); // 0x01 -> Set PPU MSB
Serialport.write(0x02, 0x00); // 0x02 -> Set PPU LSB
for(int i=0; i < message.length; i++)
{
   Serialport.write(0x04, message[i]); // 0x04 -> Write tile to screen with blip - increment to next position
}

That's it - the program gives you full access to the PPU/APU (sort of like an API) so you can pretty much do whatever you want with it. Should be handy for VJ applications - back to working on FaMI!

PC->NES Speed improvement!

2010-08-01T22:51:00.006-04:00

So I've been wrestling with the timing of the transfer tool. The Arduino end is a huge unknown since I can't get access to the underlying assembly. The good news is I figured out what was blowing the timing. I had 2 bytes being sent each time - pretty much like a PISO (parallel in serial out) shift register. The way I was doing it originally was

PORTC = (byteToSend1 >> bitIndex);

Which was fine, but in the worst case it would have to shift the value 15 times.
Instead I made the change persistant:

byteToSend1 = (byteToSend1 >> 1);
PORTC = (byteToSend1);

Which ensures each bit only needs to be shifted once!

Arduino->NES Transfer Tool + FaMI - Family MIDI

2010-07-30T01:16:00.013-04:00

I've been working at a serial connection to the NES for a few months now. At first I came up with a board to try and establish a serial line to the NES through the controller port - I only made 2. They worked - but I figured that it was possible to do it without the board if I did some tricky stuff with the ATMega interrupts on the Arduino. After a few days of debugging (and cycle counting) it’s working flawlessly. The advantage of this over a software serial based approach is that the Arduino acts as a buffer that’ll hold incoming messages (up to 128 bytes) until the NES is ready to get the next one. This means that the NES is free to do other things and doesn’t need to spend time polling the controller port! The latency is extremely low - about as fast as the NES could handle - faster than the MIDI standard. The serial code is compact and easily relocatable - it works great as a replacement to any controller code. Working on a new name for this since it really just acts like a bridge between your PC and the NES. Both the ROMs and the Arduino stuff will be open source so if you have the hardware you're ready to go!

Arduino->NES Transfer Tool features:

PRG Upload (2K max ($6000-$7FFF) - great for quickly debugging small programs)
CHR-RAM Uploader - CHR banks / nametable data
Full PPU control (palette / scroll registers / mirroring etc..)
Full sound register control

Demo video of PRG/PPU uploading. First the transfer tool is loaded from the powerpak - then glitchNES is uploaded over serial- then from there a couple of new CHR banks are loaded while glitchNES is running.

Example software: (I'll upload videos as I record them)
PRG Upload for fast development cycle on real hardware
Bridge PC data through serial - (ex. network data sent over serial to Twitter client)
Analog sensor input for alternate controls
MIDI CC control of glitchNES
Atari punk type console using the APU
Hardware NSF player

What you need:

An NES
Arduino Duemilanove or equivalent (testing RBBB this weekend - should be no problems)
Desoldered NES controller cord (I have about 50 of these that I intended to use for the boards)
Powerpak or other devcart (All software is currently using NROM (PRG-ROM + CHR-RAM) to make things simpler)
Optional: MIDI-in circuit for Arduino for FaMI

- That’s it! No internal modification / extra components needed. It took a while to get the Arduino to handle everything but it was worth it to eliminate any external components. Just hook up the wires to the Arduino / run the software and pop that badboy into port 2.

And... presenting...

FaMI (Family MIDI) - Open source NES MIDI software + live visualization by NO CARRIER

Right now channels 1-4 are working with no issues. There aren't any effects yet - but it’s completely stable / performance worthy in the state that it’s in. I'll be working on pitch bends / cc control in the next couple of weeks - but it's open source so hopefully people will develop beyond that! The samples work but they are fixed- I’m working on a mapper for powerpak right now that may allow sample uploading.

What’s great about using this Arduino setup is that you can use VBlanks MIDI->serial processing app so you don’t even need to build a MIDI circuit - just use the USB cable!

I’ll be releasing the source code for the Arduino/ROMs within the next week after I clean up the code/comment. I'm hoping to have a suite of audio/VJ tools that are ready to run so I’m looking for inspiration as to what else to use this stuff for! So please let me know if you have any ideas!

Thanks to
+ NO CARRIER for FaMI name / logo / layout
+ bucky for the encouragement / pitch tables
+ Animal Style / enso / entire Philly crew for being awesome dudes.
+ neilbaldwin and blargg for inspiration to finish this NES stuff

Oh yeah I've got a bunch of desoldered controller cables (40+) - if you're going to pulsewave this weekend and have the hardware to try this out, let me know! I'll bring you one so you don't have to destroy a controller - free of charge - just help me test this stuff!

Homebrew - Honey Brown Ale

2010-07-06T20:37:00.003-04:00

Honey Brown Ale - can't wait to try it.

8static handouts

2010-07-06T20:34:00.002-04:00

Etched some handout boards for a PCB workshop I held at 8static a few months back. Learned that 2oz copper takes forever to etch - still came out pretty awesome with the black glass.

Famicom Fixed - Part 2

2010-06-07T20:39:00.003-04:00

So I bypassed the fuse while looking for a 1:1 in replacement. I only found one distributor with the same picofuse as the fami - so I tried a replacement with a 1.5A that I already had. I clipped the leads off of the old one and dropped the new one in. The caps are a bit tricky to solder to, roughing them up a bit with some sandpaper does the trick.

Good as new!

Fixed Famicom

2010-05-13T13:02:00.003-04:00

enso enso enso (I'd advise you to check out all 3) gave me a dead Famicom, we felt that it was our civic duty to bring her back to life.

Followed every damned trace on that power supply, I was really surprised to find a fuse in there, as far as I know the NES doesn't have one.
Anyway, replaced 2 caps + voltage regulator + fuse and this baby came right back to life!

No charge of course - just let me play Bird Week for a couple of days.

Family Twitter

2010-05-04T21:13:00.006-04:00

http://www.boingboing.net/2010/05/04/famicase-gallery-201.html
"Yeah, you can joke, but I'll bet you that someone, somewhere, has got this actually working in an emulator."

I'll take that bet, and I'll raise you some real hardware.

Laptop processes live twitter data and sends it via serial to Arduino, NESShield plugged in player 2. I'll fancy it up a bit with some graphics once I'm settled in to the new apartment.

Got a new scope!

2010-04-01T17:25:00.008-04:00

Ah, I finally own a digital scope :)

A quick capture of the CLK line coming out of the NES (take a look at the 1/x measurement, reads as 1.79Mhz exactly, same as NTSC NES clock!).

Arduino PWM test

scrollNES Released!

2010-01-16T14:28:00.005-05:00

Teamed up with NO CARRIER for a ROM release!

scrollNES is a dynamic text scrolling routine for the NES by NO CARRIER & Batsly Adams. It's useful for intros, live visuals, or whatever else you need! Click here to download it! Click here to view a video version of the "readme.nes" intro that is included with scrollNES, which shows off what you can do with it.

Look out for more software from us! In the meantime, check out some great stuff here.

GlitchNES - Adjustable Delay

2009-12-28T12:08:00.005-05:00

Modified version of (the great) GlitchNES. Got annoyed trying to shoot video and use the controllers, so I dropped it in my Panavise Jr, hah! Drilled an enclosure with a bunch of holes to hold some pots and switches.
Single pot through Arduino board connected to the second controller port, the delay length is determined by an 8-bit value. You get some really cool glitches when you bring it up slowly. Needs some work with making the knob more "linear" (you can see that the speed ramps up kind of quick at the end of the turn). That means I have to start counting cycles.. ugh. Maybe I'll shuffle the palette with the second knob.

NES Arduino - Diagnostic Cart Video

2009-12-25T13:01:00.005-05:00

I've learned a lot making these boards. A few things to note:

- Measure twice, cut once. I inadvertently connected a trace that didn't belong in the first board. I had to cut it with an exacto and reroute it with a small wire.
- Thoroughly clean the board before trying to transfer the toner, and make sure you grab it by the sides! The cleanest hands will still put a nice smudge on the board. I had to tin some tracks on the second board (which is why it looks so sloppy from the bottom)
- It's difficult to solder to a pad that has been drilled incorrectly, even when using proper technique. Soldering on a SparkFun board pad seems to magically take on a shiny teardrop shape, this board does not!
- You CAN cut 0.30 PCB with a pair of scissors, but you'll dull them out after a handful of boards

At any rate, if you have a project in mind and you're putting it off because the details are daunting, please just try it. You'll learn so much in the process.

NES Arduino - Diagnostic Cart

2009-12-24T22:56:00.005-05:00

Yes! Everything worked as expected. The bits are all in the right place which means we can use as many shift registers as we're willing to clock. I forgot to fix the palette, but I kind of like the way it looks. The bits running along the top of the screen correspond directly to the pins beneath them.

Update: Fixed palette, more components

NES Arduino PCB - v0.3

2009-12-24T21:37:00.006-05:00

So I'm kind of enjoying the revision process.

The original designs were using the digital outputs from 0-14. This is still good for using everything internal to the Arduino, but 0 and 1 are used for serial communication. Don reminded me of the potential of using the PC for control, so I remade the board with a few changes.
- Digital pins 2-13 are used (12 bits of control) to free up serial communication
- The MSB is properly wired, this is something I had fixed in software, but now the pins are mapped more naturally (LSB of arduino matches LSB of button register after latch/clocks)
- I still used the ground plane, but with more isolation to avoid bridging any soldering points (again)

I'm writing up a diagnostic tool to verify that everything is being received properly. I'll use it for any boards I produce after to make sure all the bits are working.

NES Arduino PCB - v0.2

2009-12-24T00:12:00.006-05:00

The new revision grabs the Arduino ground off the board which eliminates that extra wire. I also chained together 2 shift registers to make use of all of the Arduino digital outs. So now the board has 14-bits of control through a single NES port. I'm using some new 1/2 oz copper boards and they give a nice clean etch! I dig the clear board too.

Well I drilled the board (almost destroyed the last pad too), soldered everything together and popped in the two ICs. I crossed my fingers and turned on the NES, loaded up my test program and... no joy. I did notice a strange humming sound coming out of my TV, so I did the usual sanity checks. The first chip felt pretty warm, so I unplugged the board from the controller port, and I noticed that the humming went away. I had a hunch that there was a short somewhere, I could only hope that it wasn't in my design.

Let me just say that a continuity tester is key for diagnosing these issues, you can make a simple one with an LED or make sure that your multimeter has the option. Even budget ones have this feature, mine (<$15) has an audible one, which is really handy. I started poking around, and I noticed that two pins were conducting (none should in this design!). Bastard! It's the first time I've used a ground plane fill for a board, you'll notice in the board layout below that a lot of the areas are solid. This saves on etchant and gives a clean look to the board. I guess I got sloppy though, I traced the path and found a splash of solder between VCC and GND. Yikes, I shorted the power lines. I was able to clean up the trace without much of a problem. I wired everything back up and it worked perfectly. Whew!

Finished (working) board, I'll extend the test software to 14-bit tomorrow.

NES Arduino - Palette Test

2009-12-23T21:52:00.005-05:00

The code is the same for the first controller port, the arduino/pot is in the second. I'm using 4 bits from the potentiometer and putting them into the lower nibble (hue) of the first color in the background palette. I set the intensity to 1, so if you look at the '10' row and read left to right, you should see the colors in the same order.

I guess the next step is to design an enclosure with a couple of pots/sliders for stuff like this. I got my CD4021's from digikey today, I should have enough for a handful of boards. I'm still trying to think of other things that could benefit from an analog input.

NES - Arduino shield bit shift / potentiometer test

2009-12-21T00:19:00.006-05:00

The potentiometer test worked without a hitch. The first video is running a diagnostic tool I found on nesdev (nestress). The problem was that the test would end when you hit select and start on either controller, so as I was testing the full range of values it would just quit! So I wrote up my own code in the second video to spit out the values. I had to make a few adjustments to the Arduino code to ensure that all of the outputs would be changed simultaneously, otherwise it's possible that the NES could latch halfway through a change. I'll post all code/schematics once I sort everything out, until then feel free to contact me if you have any questions!

I've also been working on additional input via the second port to GlitchNES. Right now I have the potentiometer cycle the first color of the palette, it's not much different than changing the hue on your TV, but it's still pretty cool. I'll take some pictures of it tonight.

NES - Arduino shield

2009-12-20T21:24:00.009-05:00

Stopped by blipfest this weekend, amazing music, even better people.

I had ripped a CD4021 out of an NES control a few months ago to test if I build an interface for the Arduino. It worked, but the wires got messy and when I took it back out to test they flew everywhere. I ended up designing a couple of PCBs to make things simpler. I was always worried that home etching wouldn't hold up with the small traces needed for digital design, but everything worked out great. The SparkFun parts library for EAGLE was a huge help.

First board - You can see in the top left part of the board that a drill pad and a track didn't transfer properly. I think I may have grabbed the board too far inside. The oil from my fingers probably botched the transfer. I went along with the etch anyway, since most of it was fine.

Don't even think about drilling by hand, I've done it a couple of times. Do yourself a favor, if you have a Dremel go out and buy the drill press, it's only 30 bucks!

First board in action, you can see the clip attaching the arduino ground. The next design should line up properly with the GND pin of the arduino without an additional wire.

Ran into no-carrier at blip who was also very interested in this sort of thing. With all of the innovative stuff he's put out for the community (I used glitchNES to test this!), it would be a great disservice for him to not have a board. No broken traces on this one, and the logo held very well through the transfer (no smudging).

So now I have an 8-bit lane for controlling my NES, which opens up a lot of (analog?) possibilities.

Relay Pack Interface

2009-12-03T21:20:00.004-05:00

So I finally made a gig-worthy light controller.
Eight independent channels, controlled via a DB9 connector on the side. Used electromechanical relays this time so I couldn't connect hook up the Arduino directly. A single ULN2803 transistor array sinks current from the relays, stepping the arduino logic signals up to 15V. The relays are louder than I expected, but it shouldn't be a problem if music is playing.

Wrote a quick interface for Vixen via the serial port. I used a sample sequence I had seen in a christmas light video a few years ago. I realized I don't have any lamps left in my room, so I had to use whatever I found (a ropelight, a lawnlight and a string of goofy ghost lights).

I'm hoping to do some stuff with the drumkit now that I have the 8 channels.

Woolly Mammoth clone (design)

2009-11-29T14:53:00.005-05:00

I'm going to try to design a pcb from scratch for this guy.
(both transistors are 2n3904's or equivalent)

NES Development

2009-11-29T14:19:00.003-05:00

Working on an NES synth cart, more info later.

Vinyl cutter tests

2009-06-23T07:36:00.003-04:00

Just some test cuts with a vinyl cutter I picked up for cheap.

The Bees Pedal

2009-05-12T23:51:00.002-04:00

It took a while, but I got a nice deep etch this time.

(more details later)

Drum trigger relay

2009-04-27T01:56:00.005-04:00

Well Zack had an extra piezo transducer and I always wanted to try triggering lights with a drumset. I rigged up an electromechanical relay to a simple one shot circuit with a 555 timer. There are two potentiometers to control sensitivity and pulse length. I originally rigged the relay up to a flashlight and used the battery power, but I really wanted to drive some higher power devices. So I grabbed a power strip and got to work. To improve switching speed, I used a solid state relay but it can only take 3A of current. I need to be really cautious about what I plug into this thing, the rope lights draw about 0.6A, so I should be able to run at least 4 of them comfortably. I recorded a quick test video, hitting the surrounding area doesn't trigger the piezo which is great, and you can visibly see a change in the pulse length when I adjust the pots. I didn't set anything on fire or trip a breaker, so that's even better.

The Touch Yourselves are playing Spring Fling so I'm trying to get it rigged in time for Saturday. I mean it works but I think I'd feel pretty bad if I killed Devin via electrocution.

Cyborg Scrambler - Finished

2009-04-27T01:46:00.004-04:00

Fit and lit.

I had to buy these monster potentiometers since they didn't have the regular sizes in 10Kohm and I'm too impatient to wait for them to be shipped, I figured that I could replace them if they didn't work. Well the plastic knobs don't really fit but after assembling everything we actually ended up liking the look without them.

Having a colored wiring scheme (beyond the basic power/ground) has made things a lot easier, I found an old cable harness a ton of stranded 24awg wire with a every color you can imagine.
*I'd like to point out that the "input = indigo" and "output = orange" rule that started as a joke has proven itself more times than I can count. Except for the arguments about what color indigo actually is.

Cyborg Scrambler - Painting

2009-04-18T22:15:00.006-04:00

I spraypainted the whole thing black and block sanded the paint off of top the etch. We've sanded it down so many times that the grooves aren't as deep, but I'm still really happy with the way it came out.
Green acrylic paint along the sides, some red sharpie behind the lettering and green sharpie added randomly across the entire thing.
I knew that the clearcoat would lift the marker color again when I sprayed the back of the Neck Ringer (acetone). Although it would ruin an image where I was trying to keep sharp defined edges I thought I would try to use the effect to my advantage. It ended up leaving a "glowy" look across the text and some parts of the original image.

You can see this in the pictures above, the one on the left has the red/blue marker on the text and a bit of green throughout although it is barely visible, while the picture on the right is the same pedal after applying the clearcoat. You can see how the ink was "drawn out" around the text.

I know it the side paint won't hold up forever, but the etch should be fine. I'm glad that the scratches and dents add to the look.

MAME Cabinet Work - Spring Break

2009-04-14T19:09:00.005-04:00

So haven't worked on the arcade cabinet since about 2003 when Tyler and I installed a new TV (20"->24"). There was never anything really wrong with it, but there were a lot more things I had planned to do. I'm a lot more skilled now than I was when I originally had built it (I don't know how I even managed to wire it so well). I decided to take another crack at it this spring break. (Details later)

Acid Test - Part 3 (!)

2009-03-27T03:35:00.008-04:00

I've been getting some mixed results with the acid etching on aluminum. After experimenting for a while, I think I've got a system down. I had photoshop open and I was trying to think of a new design for another enclosure. I was going through some pictures on my hard drive and ended up stylizing a picture of Riki-Oh. For this (and any two tone stuff) I tend to go grayscale, adjust brightness/contrast, use the stamp filter, then do a manual cleanup of any stuff that looks out of place.

I'll try my best to outline the process:

After printing the mirrored image onto a section of PnP blue, I ironed it on. Highest heat, no steam. Strangely enough, when I try ironing on the aluminum, if I don't apply firm pressure right away the PnP "crinkles". I don't know if it's how the aluminum handles heat or what. It actually didn't transfer all that well, but it was nothing a sharpie couldn't fix.

As you can see, you don't really want to use that much of the etchant, just enough to cover the surface. There is no good reason to etch the back and you want to be able to control the process (it IS a chemical reaction).

When the plate is dropped in, the solution should begin to bubble. It reacts a lot different than a copper board. You need to keep a close watch on it since it is an exothermic reaction. Last time I did this (scrambler), I used a diluted solution and didn't keep it in there very long. This time I let it sit for a while with the solution straight from the bottle to try to get a deeper etch. If you leave it alone too long, it will become hot enough to produce vapors, mine did. When I saw it I grabbed it and ran it under cold water to stop the acid. After I rinsed it I dropped it in again and repeated the process about 5 times. I think it became hot enough to remove some of the marker, which is a bummer, but now I know.

Here is the pedal after removing most of the ink resist with some steel wool. Now this is where I left off last time, I liked the look, but I wanted a better contrast on the design. Once it's cleaned up, the design only really shows in the right lighting.

I just took some black acrylic paint that had been sitting in our living room for a while. It seemed to be too thick so I thinned it a bit with some water. I just hit the front with a light coat of the paint in hopes that the resist parts are raised enough that I could remove it without affecting the etched portion. I think a few coats of spraypaint would work well here.

I couldn't find the bit of sandpaper that was floating around my desk so I just used a rough piece of scrap wood to sand the top. I was surprised at how well the etched parts held up, I tried scratching them with my fingernail and it was fine.

I liked the matte finish but I thought it could use a couple of layers of clear coat to protect it. It seemed to really bring out the image, and looks a lot better in person.
I think that if I'm patient enough to get the transfer done well, then touch it up with a few layers of marker, I can make a really sharp looking pedal.

Now that I have a system, I'm looking forward to the next one!

Cyborg Scrambler / Jawari Assembly

2009-03-26T22:00:00.001-04:00

So I etched that scrambler board over a month ago and I just got around to assembling it today. I taught a friend how to do the PCB transfer last week, so I had that board laying around (Jawari). The Jawari is another octave shifter that sounds something like an electric sitar, it's way cool.

The drilling looks a bit sloppy but I had to do them using a Dremel by hand with a 1/32" bit. It ended up being just fine with a bit of extra solder. Eventually I'd like to buy a column drill/press! A word of advice, if the through holes (donuts?) end up being filled when the toner transfers, make an effort to remove them. It made the drilling a lot more difficult since the bit tends to "skate" across the copper.

It took a while, but here is the Cyborg Scrambler fully assembled. I made sure to used stranded wire this time (for flexibility / reduced interference). I actually don't have two guitar cords at the moment, but I verified the voltages at several points. I'll have to wait until tomorrow to test it.

I just did a quick test to see how I should fit everything in the enclosure. I had to cut the board again to make it fit so I attached the Dremel cutting wheel. Please avoid inhaling the fiber glass dust, it's bad stuff. The new Dremel tool is the best investment I've made since I've started these projects. I had an old one that worked well for a long time, but it couldn't take many accessories/collets.

I can't wait to hear this thing.

So very brave..

2009-03-19T23:05:00.001-04:00

Godspeed Batsly, godspeed.

Random Music Box

2009-03-19T21:40:00.006-04:00

So I finished putting together the random music box. It sounds awesome. It's based on a PIC microcontroller and randomly generates music based on traditional chord progressions. There are a total of 5 square waveforms, 3 for the chords, 1 for the melody and 1 for the bass. I need to sort a few things out with the source code and add the potentiometers to level out the chorus/melody/bass. I used a digital camera so the audio/video stinks, but you get the picture.

Credit to Kevin Weekly for the original schematic/code/awesome idea.

Theremin - PCBs

2009-03-13T04:25:00.002-04:00

Now we're cookin'.

This brings me back

2009-03-13T04:07:00.007-04:00

Ray sent me a blast from the past.

MAME machine circa 2002

*

Now this is the probably the greatest thing I've ever done. I'm pretty sure that almost everything that I know now I learned building that machine. It took me weeks to figure out how to wire the thing. A friend helped me do the woodcutting, we used particle board which is too damned heavy. These pictures are from right after I finished it, I've added a bezel and a 25" CRT TV since then. I had some real fun with this thing with Tyler and Pat. I'll get into the technical details when I find the other photos.

I'll work on it again someday.

*Bonus cool satanic goat shirt from when I was thought I was a rebel

I'm sort of a maniac

2009-03-13T03:25:00.008-04:00

So I've accumulated several lab kits over the past 3 years between parts for my own projects and friends who just couldn't take engineering anymore. I was tempted to throw them out, I turned it into a project instead.

I went to Lowe's and got a roll of foam insulation for the IC's. It's about an inch thick and protects the leads of the pins nicely. I cut the foam to size to fit in some plastic jewelry bags from Michael's.

Sorting the chips was a pain, it does not get any easier no matter how much you do it. I ended up having a couple hundred IC's. I made a label for each component that needed one in Word using the Avery templates. I'll put them up if anyone wants them.

I bought 3 Stack-on parts cabinets from Ace. The drawers are a bit flimsy, but they're perfect for what I need.

I wasn't sure aboutwhat to do with the resistors, I had so many it almost didn't seem worth the trouble. I ran off a label sheet with all the resistors in the E24 series and I've been sorting them since. The drawers are sorted from greatest to smallest resistance. MΩ, 100KΩ, 10KΩ etc..

I'm sort of a maniac.

Cyborg Scrambler - Acid Test Pt. 2

2009-02-05T20:08:00.003-05:00

This time I used the press & peel to etch the front of the panel, it didn't come out as clear as I would have liked, but I think it should be better next time.

Cyborg Scrambler - Acid Test

2009-02-04T14:37:00.004-05:00

Just to make sure I didn't screw up the front, I tried acid etching the back of one of the enclosures. I made a few mistakes (the toner didn't transfer entirely which botched the text) but otherwise it looks great. I think it will work out fine for the top as long the toner transfer goes well.

The etchant behaves a lot differently with aluminum. It doesn't require very much of the solution to get the reaction going, I'll use less next time and leave it for longer to get a deeper etch. I tested a few different resists (lacquer, sharpie, black acrylic paint, and the laser toner) and they all worked very well. I plan to take pictures of the process next time when I have a lovely (Kathy or Zack) assistant to help.

Anyway, here are some pictures:

And my favorite:

Neck Ringer - Testing

2009-02-03T19:13:00.005-05:00

I took the Neck Ringer down to the lab today to test the output. I ran a 100mV pp sinusoid through a 47k resistor into the input jack with a few different known guitar frequencies.

It's working perfectly as an octave-up / frequency doubler, as shown in the oscilloscope output below:

The longer wave is the input fed from the frequency generator and the shorter wave is the output of the Neck Ringer. You can see the output will go through 2 cycles for every 1 at the input, doubling the frequency. The input wave was set to ~330hz (E4, open E) and it output a wave of ~660hz (E5, 12th fret). I noticed it also changes the shape of the wave, I don't think it's a true ring mod but you can see the wave "pinched" halfway through each cycle.

I just need to cut the board to size and get some plastic standoffs and we'll call this one done.

Ampeg Scrambler - Enclosure art

2009-02-02T14:10:00.008-05:00

So we were talking about Cyborg Justice, a badass genesis game I used to play with my cousin Pat. I decided it would look pretty cool for the ampeg scrambler clone.

I'm looking to do an acid etch on this one, but I'm going to wait for the Press n Peel first. It looks like their site was hacked, I hope my order went through okay.

The Neck Ringer - Enclosure

2009-02-01T13:22:00.018-05:00

So we wired up the thing last night and it sounds great. It seems to switch it's behavior depending on what you're playing, it's ugly, and it's awesome. Since it is also a ring mod we've decided to call it the "Neck Ringer".

I ran an front image through a couple of photoshop filters and traced it a bit. I used the same process for the chassis art that I used for the PCB, Avery label backs run through a laser printer and ironed directly onto the enclosure. It seems a lot harder to get the toner to transfer to the aluminum casing and took more than a few tries.

I sprayed a few layers of clearcoat over it to try to stop the image from scratching off. I think the acetone in the lacquer caused the smearing but only in the places where I touched it up with a sharpie. I think it would have been fine with just the toner.

Mounted the PCB/phono jacks into the case after Zack lovingly drilled the hell out of it, feels pretty solid and works perfectly. All that's left is to secure the PCB to the enclosure and add an LED / active bypass.

The Neck Ringer - PCB layout / etch

2009-02-01T13:18:00.013-05:00

I was pretty interested in creating my own PCB so I tried to find a project that I could see through from start to finish without too much frustration. I wanted to make an analog circuit and decided on an octave up/ring mod guitar pedal. I found a PCB layout for a Green Ringer clone on tonepad which is an incredible resource for this type of stuff.
I made a few modifications to the layout (namely the rad skull Zack made for a VHDL project) and printed to the backing of an Avery label sheet. I used the labels to fix the mirrored layout to the copper board and ironed it. It isn't an exact science, but after about 5 cycles of ironing and cleaning the board from botched transfers I've got a few pointers:

- Make sure you don't touch the backing or the copper board with your hands, the oil on either side will cause problems with the toner
- Print the layout to a regular sheet of paper and cut the backing to size. Place the piece directly over the layout using a label on the side you feed into the printer.
- If you do any touch-ups with a sharpie, give it a good time to dry before etching

As far as time, I had the best transfer after ironing the backing for 3 minutes, and letting it cool for 30 seconds before trying to peel it off. I warmed the bottle of etchant in a bucket of hot water, poured it into a plastic tray, and dropped the board in. I constantly agitated the solution by placing a pen under the tray and rocking it back in forth. It took 12 minutes for the copper to be completely removed, leaving this:

Yeah I know it's a sloppy soldering job, I was using an old Radio Shack iron with lead-free solder. It sticks like crazy.
I ordered a few sheets of Press & Peel, I'd like to see how it works compared to this method.

Introduction

2009-02-01T13:15:00.006-05:00

I created this site because I needed a place to keep a running log of the projects I've worked on. It beats the hell out of sending images to people over and over. If anyone is interested in any of the details of these projects let me know and I'll be happy to explain. I'll try to be consistent with the labels if you're looking for a particular project.

And Kathy is great.