Shop OBEX P1 Docs P2 Docs Learn Events
Hello from Michigan! — Parallax Forums

Hello from Michigan!

dmlandrumdmlandrum Posts: 13
edited 2012-05-06 17:02 in General Discussion
Hi. I didn't find a special "Introduce yourself" thread so I hope it's okay if I post this here.

My name's Darren, and a few of you already know me. Some time ago, I won an RS232 Propstick, and now that I finally have an application in mind for it, I thought it might be time to join in the community.

One of my biggest interests is FPGAs, and I've had it in mind for a while to build a polyphonic SID-chip-based synthesizer around an FPGA. I only have two SIDs so far, though, and I'm dead broke at the moment, so I thought I'd see what I could do with what I have. So I'm thinking about making an 8-bit polyphonic synth with the Propeller, modeled approximately on the capabilities of the SID, but with external analog filters.

I'm still diving into the documentation, so it might be a bit before I have some real questions, but I thought I'd introduce myself and give you all an idea of what I'm about. :) Thanks!

Comments

  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2012-05-03 11:00
    Hello and welcome to the forums!

    If you are referring to the SID sound chip there is already is some great code in the OBEX that emulates one that you can find here:

    http://obex.parallax.com/objects/734/

    There are also some create threads on SIDcog and other sound chip emulations on the Propeller forum.

    Robert
  • dmlandrumdmlandrum Posts: 13
    edited 2012-05-03 11:40
    Thanks! That's actually more complete than I was aiming for, so it'll make a great starting point.

    I was going to do the waveforms and ADSR envelopes on a cog, then send that out through a DAC to analog filters designed in a similar fashion to the one on the 6581. From there, I would add MIDI support and then package it up.

    And yes, I just found the MIDI In object. :)http://obex.parallax.com/objects/229/
  • Matt GillilandMatt Gilliland Posts: 1,406
    edited 2012-05-03 13:25
    Hello Darren - Welcome to the Forums! :thumb:
    -MattG
  • Ahle2Ahle2 Posts: 1,179
    edited 2012-05-03 14:02
    Welcome to the forums dmlandrum!
    The Propeller is a great microcontroller for audio generation and the community is very helpful, so I'm sure you will succeed in your goal!

    Btw, have a look at     http://soundcloud.com/ahle2/sets/sid-emulation-running-on-a/ if you are interested to hear a single cog emulating a full SID chip.

    /Johannes
  • jim N8RHQjim N8RHQ Posts: 85
    edited 2012-05-03 14:07
    Hi Darren, welcome to the forums

    jim
    -pretty much in your back yard
  • dmlandrumdmlandrum Posts: 13
    edited 2012-05-03 16:05
    Jim: Hey, you're just right up the road from me. *waves*

    Johannes: That sounds pretty good. My idea is to put the oscillators and ADSR of a SID into a cog, one cog per voice, probably six voices, then have each voice output to 2-pole LPR and HPR filter chain, much like the 6581. It's also the same filter setup as the Yamaha CS80. I'd then have a cog for MIDI in and a cog for driving a display.

    Of course, if I really want to dive in, I might consider coming up with my own oscillator structure rather than directly using the SID. I'm a senior EE student with some DSP under my belt. But I still need to get a "hello, world" working on the Prop, and we should save a more technical discussion for a different thread, anyway. :)

    Thanks for the welcome, everyone!
  • smithdavidpsmithdavidp Posts: 146
    edited 2012-05-05 03:51
    We are starting to have more and more folks from Michigan getting into Propellers these days. Maybe we should start a Michigna Prop users club lol......I'm just South of you closer to Lake St. Clare
  • JordanCClarkJordanCClark Posts: 198
    edited 2012-05-05 04:10
    We Michiganders have to stick together! I'm down by Adrian, BTW.
  • dmlandrumdmlandrum Posts: 13
    edited 2012-05-05 08:13
    I'd be down with occasional get-togethers. To be honest, I'm pretty much platform-agnostic: I use whatever I have on hand that can get the job done. I'm a big fan of open source and open hardware, but I'm not married to it. ;) I just thought the Prop with it's multiple cogs would be perfect for a polysynth, and it looks like I can make that work. I have an Arduino, I have an MSP Launchpad, I have a Digilent Nexys2, and I have this PropStick. When they finally get their supply-side sorted out, I'll get a Raspberry Pi as well.

    Now I just need to get my workbench computer set back up.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-05-05 09:27
    Living in NE Ohio, if you guys would put that club south enough, I'd like to join.
    (Wife and I are originally from Grand Rapids & Adrian)

    You guys going to make UPEC this year?

    OBC
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2012-05-05 09:38
    Oldbitcollector (Jeff) wrote: »
    Living in NE Ohio, if you guys would put that club south enough, I'd like to join.
    (Wife and I are originally from Grand Rapids & Adrian)

    You guys going to make UPEC this year?

    OBC

    Hello Jeff,

    You'll have to let me know if you get up to the Detroit area sometime.

    I don't think I will make the UPEC but I am planning on the UPENE later on this year.

    Robert
  • smithdavidpsmithdavidp Posts: 146
    edited 2012-05-05 09:45
    Well I have the Bs2, and Propeller BOE Bots and also have an Eddie on the way. I am pretty much rooted to Parallax for some reason. Mostly because of the excellent assistance you get from those in the know and the un-matched customer service and support. I started my interest, in Robotics, from a Popular Mechanics article that described how to build a Robot for under $110.00 using the Arduino for the micro controller. After some web searching I found Parallax. With ties to commercial interests, and the private sector, I knew I had to be in the right place. My previousbackground is with industrial Robots such as Nachi, Panasonic, and Fanuc. All I knew about them was inputed through a teach pendant. Mostly my job was to order, and stock, replacement servos, drive motors, or control cabinet electronic replacement parts. But those things ran at 240 to 600 VAC power supplies. Knowing all of this is what suprised me about the Bs2 and Propeller controllers. I know what it takes to make the Industrial controllersgive the proper commands to the welding Robots. Parallax has packed all those large components onto a circuit board the size of my hand. Anyway.... that's how I got here and I am happy to say that I don't regret being here.
  • smithdavidpsmithdavidp Posts: 146
    edited 2012-05-05 09:49
    I might make UPEC if I can get some things done around here. lol I'm always in Detroit two and three times a month. I go to the John Dingell Medical Center, on John R, for my medical care.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-05-05 10:07
    RobotWorkshop wrote: »
    Hello Jeff,

    You'll have to let me know if you get up to the Detroit area sometime.

    Robert

    As soon as I replace my beater (Jeep) with something a little more modern, I may take you up on that..
  • dmlandrumdmlandrum Posts: 13
    edited 2012-05-05 13:15
    The one thing I do like about Parallax is they really seem to be quite hobbyist friendly. That's one thing that worries me about my Nexys2 board: once I'm no longer a student: the dev software is suddenly out of my reach. I'm thinking about selling this and getting an Altera-based board, since Altera seems more hobbyist-friendly with their software. You don't have to be open source to be hobbyist friendly, after all.
  • smithdavidpsmithdavidp Posts: 146
    edited 2012-05-06 04:09
    I have a project that almost must be open source for it to be useful and inexpensive. I'm a Vietnam Vet with Agent Orange starting to take its toll on me. I thought that I could build a Robot that could be used for Seniors as disabled people that live alone for under $5,000.00. I started with the Bs2 Boe-Bot and learned quite a bit about programming a Robot to do what you want it to do. But alas the platform was not powerful enough for my purposes. Parallax offered the Propeller on a Boe-Bot sized circuit board that offered many more of the things I need for my project. Through learning spin code and buying sensors left and right I got a little closer to my goal. But I soon discovered that the Boe Bot chassis was not going to be large enough for my purposes. I started looking at the Stingray and Medusa chassis and finally decided to purchase the Eddie chassis. Now I will have all that I need to make my project become a reality. I also have a test platform to test any other experiments on before they go to the Eddie chassis. There are already other platforms out there for this purpose but they start at $6,700.00 and go as high as $12,700.00. The platforms I looked at all had a secondary drawback. They only had a 90 minute run time. And finally they all required a connection to an off site operator for assistance. When you are disabled or Elderly you have a limited cash flow. My platform will have the ability to call 911 in an emergency and also call family members to let them know an emergency exsists at their loved ones home. No middle man and no $100.00 a month fee for someone that makes these same calls from a call center. The programming is going to be a headache but once done, and tested, I will have that useful device and it will be affordable. Being around the chat rooms provided here and the helpfulness of the people puts me at ease knowing that I will have the guidence to assemble everything and have it work. I apologize for the wordiness but I truly am excited about the things to come.
  • dmlandrumdmlandrum Posts: 13
    edited 2012-05-06 17:02
    That sounds like a really cool project! I'm definitely behind anything that can make life easier for people, especially our veterans. Please keep up the good work!
Sign In or Register to comment.