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Propeller as USB device — Parallax Forums

Propeller as USB device

pullmollpullmoll Posts: 817
edited 2010-03-18 19:31 in Propeller 1
Excuse my ignorance, but since I didn't find anything obvious in the OBEX: would it be possible to make an USB device of a Propeller? I.e. could it act as a USB HID and play the role of a joystick, a dongle or something like this? What external part(s) would be required?

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He died at the console of hunger and thirst.
Next day he was buried. Face down, nine edge first.

Comments

  • LeonLeon Posts: 7,620
    edited 2010-03-17 21:10
    It has been done. Try searching the forum.

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    Leon Heller
    Amateur radio callsign: G1HSM
  • Erik FriesenErik Friesen Posts: 1,071
    edited 2010-03-17 22:56
    Search for "usb toys to play with" by bradc . Unfortunately parallax forum search is incapable of finding this, you'll have to use google or look back. It seems like it has been up the last month or so.
  • hairymnstrhairymnstr Posts: 107
    edited 2010-03-17 23:16
    The google trick (if you aren't already aware) is to type "site:forums.parallax.com" followed by a space and your search term into Google.

    As I recall Brad managed to get an HID profile working and some kind of boot-loading I think but it's not technically in spec for USB.

    Here's the thread http://forums.parallax.com/showthread.php?p=675656
  • Cluso99Cluso99 Posts: 18,069
    edited 2010-03-18 00:49
    You need to use the advanced google search and in the search forums box type forums.parallax.com and add to favourites. Hopefully next time you start to type the forums.... it will popup the whole text to enter.

    I think the link in my signature now does the google advanced search again.

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    Links to other interesting threads:

    · Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
    · Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
    · Prop Tools under Development or Completed (Index)
    · Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
    · Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
    My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
  • pullmollpullmoll Posts: 817
    edited 2010-03-18 07:18
    Thanks for your replies. I found BradC's code and if I look at it and read the comments, it may work but is hard at the edge of the specs. So it looks like as if I should better use some specialized USB chip and interface with that. Thanks!

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    He died at the console of hunger and thirst.
    Next day he was buried. Face down, nine edge first.
  • LeonLeon Posts: 7,620
    edited 2010-03-18 14:35
    If you need a single chip solution, I'd use a USB PIC. Here is something I designed:

    www.leonheller.com/usb/

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    Leon Heller
    Amateur radio callsign: G1HSM
  • lynchajlynchaj Posts: 87
    edited 2010-03-18 16:08
    Hi!· Thanks Leon!· That looks like a sweet project for the PropIO board and would easily fit in the prototyping area.· I've been looking for an easy way to add USB so that just might be it.· There appears to be plenty of spare IO pins on the PIC to tie back to the Propeller too.· Is the PIC 3.3V tolerant or does it require 5V?· I think USB requires 5V.

    Great post!· Thanks and have a nice day!

    Andrew Lynch
  • LeonLeon Posts: 7,620
    edited 2010-03-18 16:34
    That PIC is rated for 2V to 5V operation. It operates off 5V in that circuit.

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    Leon Heller
    Amateur radio callsign: G1HSM
  • jazzedjazzed Posts: 11,803
    edited 2010-03-18 16:43
    pullmoll said...
    I found BradC's code and if I look at it and read the comments, it may work but is hard at the edge of the specs.
    If you take the time to test it, you may find that it suits your needs. There are a few complications with PC side drivers that may not appear with other solutions though; the issues are detailed in BradC's thread. If your Propeller is already very busy doing other things, an external solution may be best. I was very pleased with the results using BradC's code for serial port communications especially since I had no room for extra hardware.

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    Short answers? Not available at this time since I think you deserve more information than you requested.
  • hairymnstrhairymnstr Posts: 107
    edited 2010-03-18 19:09
    I've successfully used a USB enabled PIC (18F4550) although it's pretty hard work it seems to me. PICs will run in a with a wide range of supply voltages but you need to be cautious about the PLL stability, in production I've found it is not good at 3.3V. The USB capable PICs contain a 3.3V regulator in them as USB signalling is at 3.3V. USB supply is nominally 5V but anything down to about 4.5V is in spec, and in practice I've seen down to about 4V.

    My favourite solution is always an FTDI chip, they're really flexible and you don't need to do any of the low level stuff yourself. I particularly like the asynchronous-parallel mode ones (like the venerable FT245). These have a standard 8 bit FIFO interface so plug into any basic micro-processor style bus with ease and work well at 3MBaud+ and you can code the interface as if they were just a normal serial port (just the normal FTDI drivers).
  • Cluso99Cluso99 Posts: 18,069
    edited 2010-03-18 19:31
    This USB Prop PRogrammer was just posted by Nick http://forums.parallax.com/forums/default.aspx?f=25&m=437387

    Maybe it could do the job?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Links to other interesting threads:

    · Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
    · Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
    · Prop Tools under Development or Completed (Index)
    · Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
    · Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
    My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz
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