Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

From	Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP>
Newsgroups	comp.arch.embedded
Subject	Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs
Date	2012-12-18 13:06 +0000
Organization	A noiseless patient Spider
Message-ID	<kappnr$v0g$1@dont-email.me> (permalink)
References	(7 earlier) <kan6kp$1ai$1@dont-email.me> <kauuc8d6soqaomu7s4r1fjgp472iri6kh4@4ax.com> <g2vuc8p69duur3rc5762tt94svvn7be0re@4ax.com> <20121217233648.1383b6cb@kruskal.chead> <e970d8ls4j8b79ugifet1cbc92ac512fnq@4ax.com>

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On 2012-12-18, Jon Kirwan <jonk@infinitefactors.org> wrote:
>
> Doesn't sound like where I'd like to be. I am thinking, say,
> about hooking up a standard, cheap, PC keyboard to a ...
> well, let's say an MSP430 with ... let's give it 16k flash
> and 512 bytes sram total. Hmm. There are six different ones
> with that spec. Three at $1 and three at $2.
>
> Any chance? It is just a keyboard, after all.
>

I have not done anything with the HID layer yet so I don't have a
feeling for what is involved there. However, Microchip have fitted
both a CDC layer and a HID layer (to control GPIO lines, not a
keyboard) into it's MCP2200 device. The MCP2200 is widely reported
to just be a PIC18F14K50 with custom Microchip firmware.

I don't know how the code density of the PIC18 compares with the MSP430
but that should give you a feeling for what is possible on the PIC18.

Note that this does not take into account the additional code needed to
poll the keyboard and also note the PIC18F14K50, when you add in the 256
bytes of USB RAM in bank 2, has 768 bytes of SRAM in total compared to
the 512 bytes you mention above for your MSP430 device.

Here is Microchip's PIC18F14K50 page so you can compare it to your
MSP430 device:

http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en533924

I am not familiar with the MSP430 range. Is the USB device controller
in the MSP430 you are looking at a high speed, full speed or a low
speed controller ?

I see TI have a PDF writeup about creating a USB keyboard using a full
speed MSP430 device connected to a keyboard:

http://www.ti.com/general/docs/lit/getliterature.tsp?literatureNumber=slaa514&fileType=pdf

Simon.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world

Thread

baud rate autodetection on AVR 8-bit? Ivan Shmakov <oneingray@gmail.com> - 2012-12-07 21:17 +0700
  Re: baud rate autodetection on AVR 8-bit? Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-12-07 10:28 -0500
    Re: baud rate autodetection on AVR 8-bit? Ivan Shmakov <oneingray@gmail.com> - 2012-12-07 23:31 +0700
      Re: baud rate autodetection on AVR 8-bit? Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-12-07 12:42 -0500
        Re: baud rate autodetection on AVR 8-bit? mike <ham789@netzero.net> - 2012-12-07 13:35 -0800
          Re: baud rate autodetection on AVR 8-bit? Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-12-07 20:07 -0500
          Re: baud rate autodetection on AVR 8-bit? Mark Borgerson <mborgerson@comcast.net> - 2012-12-07 23:43 -0800
      Re: baud rate autodetection on AVR 8-bit? Tim Wescott <tim@seemywebsite.com> - 2012-12-07 13:07 -0600
      Re: baud rate autodetection on AVR 8-bit? Dave Nadler <drn@nadler.com> - 2012-12-07 12:09 -0800
        Re: baud rate autodetection on AVR 8-bit? Ivan Shmakov <oneingray@gmail.com> - 2012-12-08 03:47 +0700
          Re: baud rate autodetection on AVR 8-bit? MK <mk@nospam.co.uk> - 2012-12-08 09:44 +0000
            8-bit vs. 32-bit MCU's Ivan Shmakov <oneingray@gmail.com> - 2012-12-08 18:31 +0700
              Re: 8-bit vs. 32-bit MCU's MK <mk@nospam.co.uk> - 2012-12-09 14:13 +0000
                Re: 8-bit vs. 32-bit MCU's Ivan Shmakov <oneingray@gmail.com> - 2012-12-09 22:52 +0700
    Re: baud rate autodetection on AVR 8-bit? upsidedown@downunder.com - 2012-12-08 15:01 +0200
  Re: baud rate autodetection on AVR 8-bit? Dombo <dombo@disposable.invalid> - 2012-12-08 15:18 +0100
  Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] Glenn <glenn2233@gmail.com> - 2012-12-09 10:47 +0100
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] "Paul E. Bennett" <Paul_E.Bennett@topmail.co.uk> - 2012-12-09 10:22 +0000
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] "Bruce Varley" <bv@NoSpam.com> - 2012-12-09 19:07 +0800
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] Paul <paul@pcserviceselectronics.co.uk> - 2012-12-09 13:27 +0000
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232   ? ] Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2012-12-09 16:19 +0100
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] "TTman" <pcw1.cad@ntlworld.com> - 2012-12-09 15:38 +0000
      Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] amdyer@gmail.com - 2012-12-09 07:45 -0800
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] upsidedown@downunder.com - 2012-12-09 17:45 +0200
      Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] Paul <paul@pcserviceselectronics.co.uk> - 2012-12-09 21:30 +0000
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] John Larkin <jjlarkin@highNOTlandTHIStechnologyPART.com> - 2012-12-09 09:02 -0800
      Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] Lanarcam <lanarcam1@yahoo.fr> - 2012-12-09 18:13 +0100
        Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] upsidedown@downunder.com - 2012-12-09 19:44 +0200
        Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] Paul <paul@pcserviceselectronics.co.uk> - 2012-12-09 21:32 +0000
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] Robert Wessel <robertwessel2@yahoo.com> - 2012-12-10 00:35 -0600
    Re: baud rate autodetection on AVR 8-bit? [ User friendly RS-232/EIA-232 ? ] josephkk <joseph_barrett@sbcglobal.net> - 2012-12-12 20:30 -0800
  Re: baud rate autodetection on AVR 8-bit? "Meindert Sprang" <ms@NOJUNKcustomORSPAMware.nl> - 2012-12-10 13:38 +0100
    Re: baud rate autodetection on AVR 8-bit? Ivan Shmakov <oneingray@gmail.com> - 2012-12-10 20:19 +0700
      Re: baud rate autodetection on AVR 8-bit? "Meindert Sprang" <ms@NOJUNKcustomORSPAMware.nl> - 2012-12-10 16:24 +0100
        Re: baud rate autodetection on AVR 8-bit? Arlet Ottens <usenet+5@c-scape.nl> - 2012-12-10 16:49 +0100
        Re: baud rate autodetection on AVR 8-bit? Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-12-12 08:50 -0500
  Re: baud rate autodetection on AVR 8-bit? j.m.granville@gmail.com - 2012-12-11 21:22 -0800
    Re: baud rate autodetection on AVR 8-bit? Robert Wessel <robertwessel2@yahoo.com> - 2012-12-12 00:29 -0600
      Re: baud rate autodetection on AVR 8-bit? Mark Borgerson <mborgerson@comcast.net> - 2012-12-11 23:43 -0800
        Re: baud rate autodetection on AVR 8-bit? Robert Wessel <robertwessel2@yahoo.com> - 2012-12-12 02:38 -0600
          Re: baud rate autodetection on AVR 8-bit? Mark Borgerson <mborgerson@comcast.net> - 2012-12-12 07:46 -0800
            Re: baud rate autodetection on AVR 8-bit? linnix <me@linnix.info-for.us> - 2012-12-12 10:50 -0800
              Re: baud rate autodetection on AVR 8-bit? Jon Kirwan <jonk@infinitefactors.org> - 2012-12-12 12:42 -0800
                Re: baud rate autodetection on AVR 8-bit? Jon Kirwan <jonk@infinitefactors.org> - 2012-12-12 12:56 -0800
                Re: baud rate autodetection on AVR 8-bit? upsidedown@downunder.com - 2012-12-12 23:22 +0200
                Re: baud rate autodetection on AVR 8-bit? Robert Wessel <robertwessel2@yahoo.com> - 2012-12-12 15:39 -0600
                Re: baud rate autodetection on AVR 8-bit? Jon Kirwan <jonk@infinitefactors.org> - 2012-12-12 15:13 -0800
                Re: baud rate autodetection on AVR 8-bit? Jon Kirwan <jonk@infinitefactors.org> - 2012-12-12 15:28 -0800
                Re: baud rate autodetection on AVR 8-bit? Robert Wessel <robertwessel2@yahoo.com> - 2012-12-12 18:41 -0600
                Re: baud rate autodetection on AVR 8-bit? Jon Kirwan <jonk@infinitefactors.org> - 2012-12-12 17:12 -0800
              Re: baud rate autodetection on AVR 8-bit? Mark Borgerson <mborgerson@comcast.net> - 2012-12-12 12:43 -0800
                Communications under pressure (was Re: baud rate...) Frnak McKenney <frnak@far.from.the.madding.crowd.com> - 2012-12-13 10:25 -0600
                Re: Communications under pressure (was Re: baud rate...) Robert Wessel <robertwessel2@yahoo.com> - 2012-12-13 12:34 -0600
                Re: Communications under pressure (was Re: baud rate...) upsidedown@downunder.com - 2012-12-14 10:33 +0200
                Re: Communications under pressure (was Re: baud rate...) Mark Borgerson <mborgerson@comcast.net> - 2012-12-14 07:43 -0800
                Re: Communications under pressure (was Re: baud rate...) Mark Borgerson <mborgerson@comcast.net> - 2012-12-13 16:47 -0800
                Re: Communications under pressure (was Re: baud rate...) Jon Kirwan <jonk@infinitefactors.org> - 2012-12-13 18:22 -0800
                Re: Communications under pressure (was Re: baud rate...) Jon Kirwan <jonk@infinitefactors.org> - 2012-12-13 18:27 -0800
                Re: Communications under pressure (was Re: baud rate...) Mark Borgerson <mborgerson@comcast.net> - 2012-12-13 23:20 -0800
                Re: Communications under pressure (was Re: baud rate...) Frank Miles <fpm@u.washington.edu> - 2012-12-14 17:50 +0000
                Re: Communications under pressure (was Re: baud rate...) Mark Borgerson <mborgerson@comcast.net> - 2012-12-14 14:28 -0800
          serial host-to-device communication in amateur designs Ivan Shmakov <oneingray@gmail.com> - 2012-12-14 23:21 +0700
            Re: serial host-to-device communication in amateur designs Rob Gaddi <rgaddi@technologyhighland.invalid> - 2012-12-14 09:18 -0800
              Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-14 11:19 -0800
                Re: serial host-to-device communication in amateur designs Ivan Shmakov <oneingray@gmail.com> - 2012-12-16 21:00 +0700
                Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-16 13:46 -0800
                USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-17 00:53 +0000
                Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-16 17:46 -0800
                Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-17 13:27 +0000
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Mel Wilson <mwilson@the-wire.com> - 2012-12-17 10:32 -0500
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs me@linnix.info-for.us - 2012-12-17 11:13 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-17 12:03 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-17 12:17 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Christopher Head <chead@is.invalid> - 2012-12-17 23:36 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-17 23:54 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-18 13:06 +0000
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs j.m.granville@gmail.com - 2012-12-18 14:04 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-18 14:13 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Christopher Head <chead@is.invalid> - 2012-12-19 02:37 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-19 12:59 +0000
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Rocky <RobertGush@gmail.com> - 2012-12-19 10:19 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-19 10:43 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-19 10:39 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-19 10:44 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Christopher Head <chead@is.invalid> - 2012-12-19 18:42 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-19 21:05 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-20 14:13 +0000
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-20 11:58 -0800
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Waldek Hebisch <hebisch@math.uni.wroc.pl> - 2012-12-24 00:41 +0000
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Waldek Hebisch <hebisch@math.uni.wroc.pl> - 2012-12-24 15:45 +0000
                Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-24 11:40 -0800
                Re: serial host-to-device communication in amateur designs Frnak McKenney <frnak@far.from.the.madding.crowd.com> - 2012-12-20 10:00 -0600
                Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-20 11:54 -0800
                Re: serial host-to-device communication in amateur designs Rob Gaddi <rgaddi@technologyhighland.invalid> - 2012-12-20 12:01 -0800
                Re: serial host-to-device communication in amateur designs Jon Kirwan <jonk@infinitefactors.org> - 2012-12-20 12:27 -0800
            Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-14 17:53 +0000
              Re: serial host-to-device communication in amateur designs Ivan Shmakov <oneingray@gmail.com> - 2012-12-15 01:26 +0700
                Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-14 19:30 +0000
                Re: serial host-to-device communication in amateur designs Ivan Shmakov <oneingray@gmail.com> - 2012-12-15 11:25 +0700
                Re: serial host-to-device communication in amateur designs Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2012-12-17 00:29 +0000
                Re: serial host-to-device communication in amateur designs me@linnix.info-for.us - 2012-12-17 11:05 -0800
                Re: serial host-to-device communication in amateur designs Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-12-14 14:34 -0500
                Re: serial host-to-device communication in amateur designs Paul <paul@pcserviceselectronics.co.uk> - 2012-12-14 23:25 +0000
                finer pitches Ivan Shmakov <oneingray@gmail.com> - 2012-12-16 20:48 +0700
              Re: serial host-to-device communication in amateur designs Mark Borgerson <mborgerson@comcast.net> - 2012-12-14 21:26 -0800

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