WTPA And Related Goodies for that A**
Fri Nov 20 13:10:48 EST 2009
What is this stuff?
Where's the Party At, Hardware Version 1.01
WTPA is a very full featured 8-bit sampler kit, but you already know that if you're looking at it here.
So a last few Caveat Emptor-type words before you buy it:
- The WTPA kit comes with all the electrical components to make a WTPA, including a pre-programmed MCU.
- So like, um, it's a KIT. That means you have to solder all the parts together, and THEN it looks like the above picture (oscilloscope not included).
- You can buy bare boards and programmed MCUs below if the proper Party is too rich for your blood, or you enjoy parts sourcing challenges!
- I will be happy to solder on the SMT SRAM for you, if you don't feel like you can do it yourself. Reading the assembly manual will help you decide if you need this if you're on the fence. It takes some patience for sure, but it is a good thing to learn how to do if you don't already know.
- WTPA DOES NOT COME WITH JACKS, HEADERS, WIRE, SOLDER, OR A DC POWER SUPPLY. In beta tests, everybody wanted different options for this stuff (batteries, wall-warts, RCA jacks, 1/4" etc) so I explicitly did not include this stuff in the kit.
- HOWEVER, Like Horowitz and Hill said: Lucky for you I'm not shy about giving advice! Below you can buy a bag of my favorite audio, midi, and power jacks as well as the screws, headers and standoffs I prefer when building WTPA! If these aren't in line with what you like, Mouser or Digikey are good places to look for alternatives.
- THERE ARE NO RETURNS ON WTPA once it is opened. Sorry. It's like the little android boy in AI; it gets attached to you. I love you, and I love the kit, but the nature of electronics experiments is tied up with breaking stuff, sometimes even without realizing you've done it. Even the saintly folks at Sparkfun believe this. If you break something or even get buyer's remorse, let me know and I'll try and help you through it.
- I usually bring kits to sell when I give lectures. You can always pick up a kit from me then and skip the shipping.
On Shipping:
- As you might have guessed, I'm not a web programmer :-) This is my justification for relying on the total wing wang mess that is the Paypal "calculator" to handle shipping charges. I have this currently broken down into the following culturally sensitive and geographically finely-tuned categories:
- 1.) People in the USA.
- 2.) Other people. This is my secret "Obama is in office so now you all need a new reason to hate us" ploy.
- Shipping within the USA is via UPS Ground and is $10 for most orders (unless you get a lot of stuff).
- Shipping anywhere else in the world is $15 USD and is via USPS Flat Rate Priority Mail (again, unless you buy too much stuff to fit in the normal box).
- PLEASE don't ask me to ship via some other method unless:
- You're buying a lot of stuff and standard shipping doesn't make sense OR
- You live near me (currently Brooklyn) and want to pick it up from me somewhere.
- I am an immensely pokey shipper. I ship once a week (usually on Friday) so if you've ordered and you haven't heard anything in over seven days, feel free to nag.
Caveats now aside, Godspeed and give 'em Hell.
KITS SOLD OUT AS OF Fri Nov 20 13:04:10 EST 2009 -- Goodies are still available, though.
Hardware Goodie Bag for WTPA
I've gone through about a million different jacks and connectors and mounting methods for WTPA, and the above stuff is pretty much what I use to build it every time now.
Included in the bag are:
- (2) Panel Mount 1/4" Audio Jacks -- 3/8" mounting hole.
- (2) Panel Mount MIDI jacks -- 5/8" mounting hole.
- (1) DC Power Jack w/ Internal Switch -- 5/16" mounting hole. This is a normal DC Barrel Connector which fits 2.1mm ID / 5.5mm OD connectors (which is the same size as Radio Shack Type "M" if you have any of those lying around). The internal switch can be used to switch batteries in and out of circuit when the plug is removed/inserted.
- (1) 6-Pin ISP header (used to reprogram your AVR while it's on the board).
- (1) 16-pin 0.1" spaced pinheader. You can cut this up to make headers for all the in/outs on WTPA and then use female headers as quick connects, which I do sometimes, depending on what I'm using WTPA for. They're handy.
- (4) #6-32 1/2 inch screws. These fit the mounting holes on WTPA.
- (4) #6-32 nuts. These fit the screws that fit the mounting holes on WTPA.
- (4) #6-32 threaded aluminum hex PCB standoffs. Use these to space WTPA from any flat surface you mount it to. Allows you to use a metal chassis without shorts, or any other chassis without the PCB getting all tippy and cattywumups.
- (4) #4-40 1/2 inch screws. These fit the MIDI jacks.
- (4) #4-40 nuts. These fit the screws that fit the MIDI jacks. However, I recommend you use tapped holes for the screws if you can instead of the nuts. The nuts work but they're awkward to tighten.
This hardware kit was made with an 1/8" panel thickness (or less) in mind for all the hardware. If you are using something thicker (like 1/4") then the #6 screws will not be long enough to go all the way through the panel, standoff, PCB, and still have enough room for the nut to go on. You can buy 6-32 screws from just about any hardware store and always from McMaster which has got to be the greatest place in the world.
$15 gets you all this shiny hardware!
WTPA Version 1.00 Bare PCB
This is the the secret Suge Knight revision PCB, offering a certified 100% Biggie Free Environment.
But srsly y'all. Those of you who follow my "blog" know that I messed up and the first revision of the PCB I ordered for WTPA had a bug in the overdub summing amplifier. The bad news is I lost a lot of scratch, because I wanted everything to be perfect and revved and re-ordered all the boards.
The good news is, a few days later I started doing the overdubbing in the digital domain and stopped using the overdub summing amp audio path altogether ANYWAY. Which rendered these boards un-broken again.
They are a little less pretty, there are a couple more components, and the signal routing is just a hair noisier, but they will do EXACTLY THE SAME THING as a v1.01 WTPA if you make one. I'm not selling the bare v1.01 WTPA boards because it will screw up my math and parts counts, so if you are looking for a real deal, get this PCB, source the parts yourself, and get crackin. The parts list is 99% similar to the r1.01 boards which are in a doc on the main page. Sometime soon when I get my act together more I'll make a pdf that details the differences but it hasn't happened yet.
Twelve bones.
Pre-Programmed Atmega 164p
BRACE YOURSELF: This is an MCU pre-loaded with the most recent WTPA firmware. If you're sourcing all the parts for a WTPA PCB or engaging in some other kind of roguery, and don't have the tools or inclination for programming an AVR, or you just broke your old one, or absolutely MUST HAVE the latest firmware and can't put it on a chip, then this is for you.
It bears mentioning (again) that the code is open source, and if you know somebody with an STK500v2 or other compatible AVR programmer, you can put it on the chip for free. If not, hey, I understand. Sometimes I drop off my laundry. It's kind of the same thing.
NOTE: The full WTPA kit already comes with one pre-programmed MCU.
Eight dollars fifty. Quite a deal if you figure out the price per opcode!
As always, if there's something here you expect to see and don't, let me know, and I'll get crackin on it. As ever, thanks so much for all of this, and I remain,
Yours,
Todd