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baud rate autodetection on AVR 8-bit?

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  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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#10864 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Wednesday, December 19, 2012 2:59:12 PM UTC+2, Simon Clubley wrote:

> I do know there's a AVR based software-only USB stack but it is USB device
> only and only supports low speed connectiosn to a host PC; it does not
> have any host support.

FTDI also do a host device - AFAIK with own processor etc - "VINCULUM" was what it used to be called.

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#10866 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Wed, 19 Dec 2012 12:59:12 +0000 (UTC), Simon Clubley
<clubley@remove_me.eisner.decus.org-Earth.UFP> wrote:

>On 2012-12-19, Christopher Head <chead@is.invalid> wrote:
>>
>> You are right that my advice earlier about using libusb sounded
>> completely wrong. I thought you were trying to build a USB device, not
>> a USB host. They?re very different problems, so ignore my earlier
>> message!
>>
>
>That's exactly what I thought as well and it's what my responses have
>been assuming. When Jon then talked about adding a keyboard, I thought
>he was planning to learn about USB by combining a PS/2 (or similar)
>keyboard with a USB device capable MCU to create a USB based keyboard.
>Now I don't know. :-)

See my response to Christopher.

>Jon, are you planning to connect a PS/2 type keyboard to a MSP430 and
>then create a USB keyboard for use with a host PC

No.

>or are you wanting to
>take a USB keyboard and connect it to a MSP430 with the final destination
>target for the keystrokes been a program running on the MSP430 itself ?

Yes.

>If it's the former, you only need a MCU with USB device support and there
>are plenty of those. If it's the latter, then as already mentioned you
>are going to need to a MCU with USB host capability and the most hobbyist
>or student friendly of those (if they are building their own circuits)
>is probably the PIC32MX.

I love the PIC32 processor family and am already ramping up
skills there. But it is overkill for some other applications
and would drive up cost, size, and power consumption to the
point of killing the idea.

>I do know there's a AVR based software-only USB stack but it is USB device
>only and only supports low speed connectiosn to a host PC; it does not
>have any host support.

Yes, and there is one for a PIC16:

http://www.lendlocus.com/?q=16fusb

It's been mentioned here before. But both the AVR and PIC
projects merely point in a direction. I'm curious about the
more difficult question.

Jon

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#10865 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Wed, 19 Dec 2012 02:37:52 -0800, Christopher Head
<chead@is.invalid> wrote:

>On Tue, 18 Dec 2012 14:13:46 -0800
>Jon Kirwan <jonk@infinitefactors.org> wrote:
>
>> But I think, if all I need is a stripped down host support
>> for a keyboard then perhaps I can fit it. The question is
>> about knowledge to know for sure.
>
>Code-wise, supporting just keyboards is certainly easier than supporting
>a wider variety of devices, and if you use BOOTP, even easier than
>supporting a full variety of *input* devices. BOOTP is a simplified
>form of HID protocol intended for use by things like embedded systems
>and BIOS configuration menus; keyboards (and I think mice) support it.
>However, you will still need "full" host support at the hardware level.
>This is a property of USB: the hardware for a host is somewhat
>different to (and bigger than) the hardware for a device. It’s not
>physically possible to take a chip that does device mode only and hack
>around it to do any kind of host mode. I’m afraid I’m not familiar with
>the MSP430 series, but I do know that the STM32F4 series does host
>mode, as do some of the higher-end PICs (which jg mentioned). You sound
>like you’re looking for something pretty low-end, though, and I agree
>with jg, you’re unlikely to find such a chip.
>
>You are right that my advice earlier about using libusb sounded
>completely wrong. I thought you were trying to build a USB device, not
>a USB host. They’re very different problems, so ignore my earlier
>message!

I know that the hardware is different. That's not the issue
for me. What's important is the software behind it and how
complex it must be. There already are several project web
sites I've visited which implement USB, monitoring the Sync
Pattern in software and doing the NRZI encoding in software
using standard I/O pins coupled to the required hardware for
attaching to USB host ports. No hardware support is used if I
understand what I've read (I may not have.)

I do NOT know if similar things can be done for a host-side
implementation to support ONLY a USB-only keyboard, or not. I
mean a keyboard that does NOT support PS/2 mode. (I have
complete docs on doing that.) Not all keyboards support a
connection via either USB or PS/2.

I already know how to talk with PS/2 (I have the original
docs from IBM still and have used that information before --
did you know that the BIOS supports downloading code via the
keyboard interface?)

I'm curious about the idea of supporting USB-only keyboards
with processors which do not have any USB peripheral support
at all. It's likely that it isn't worth the trouble in a real
product, but I'm curious partly because some of the products
I've worked on before succeeded because they did things with
better margins, less power, and smaller size than the
competition using processors that were less obvious choices.

Jon

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#10867 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Wed, 19 Dec 2012 10:39:30 -0800, I wrote:

>No hardware support is used if I
>understand what I've read (I may not have.)

I mean... "No peripheral hardware support within the cpu ..."

Jon

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#10868 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Wed, 19 Dec 2012 10:44:43 -0800
Jon Kirwan <jonk@infinitefactors.org> wrote:

> On Wed, 19 Dec 2012 10:39:30 -0800, I wrote:
> 
> >No hardware support is used if I
> >understand what I've read (I may not have.)
> 
> I mean... "No peripheral hardware support within the cpu ..."
> 
> Jon

I guess you might be able to do something like the V-USB project (the
software-only device-side USB stack for AVR). Maybe you would want a
bit faster CPU (just because the host-side stuff is probably a bit more
complex—though it does have the advantage that a host doesn’t need to
always watch the wires for traffic the way a device does), and it would
not be USB compliant (because a compliant USB host must support at
least low speed *and* full speed, while a device only needs to support
one or the other, and you would probably only implement low speed), but
in the limited case of plugging in USB keyboards, it might work. At
least, you could probably get it to work with *most* keyboards.

Chris

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#10869 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Wed, 19 Dec 2012 18:42:16 -0800, Christopher Head
<chead@is.invalid> wrote:

>On Wed, 19 Dec 2012 10:44:43 -0800
>Jon Kirwan <jonk@infinitefactors.org> wrote:
>
>> On Wed, 19 Dec 2012 10:39:30 -0800, I wrote:
>> 
>> >No hardware support is used if I
>> >understand what I've read (I may not have.)
>> 
>> I mean... "No peripheral hardware support within the cpu ..."
>> 
>> Jon
>
>I guess you might be able to do something like the V-USB project (the
>software-only device-side USB stack for AVR). Maybe you would want a
>bit faster CPU (just because the host-side stuff is probably a bit more
>complex—though it does have the advantage that a host doesn’t need to
>always watch the wires for traffic the way a device does), and it would
>not be USB compliant (because a compliant USB host must support at
>least low speed *and* full speed, while a device only needs to support
>one or the other, and you would probably only implement low speed), but
>in the limited case of plugging in USB keyboards, it might work. At
>least, you could probably get it to work with *most* keyboards.
>
>Chris

Thanks, Chris. That doesn't say I can't do it, or that I
necessarily can. But maybe. At least the door remains open,
so far.

I appreciate your thoughts very much,
Jon

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#10871 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On 2012-12-19, Jon Kirwan <jonk@infinitefactors.org> wrote:
> On Wed, 19 Dec 2012 18:42:16 -0800, Christopher Head
><chead@is.invalid> wrote:
>
>>On Wed, 19 Dec 2012 10:44:43 -0800
>>Jon Kirwan <jonk@infinitefactors.org> wrote:
>>
>>> On Wed, 19 Dec 2012 10:39:30 -0800, I wrote:
>>> 
>>> >No hardware support is used if I
>>> >understand what I've read (I may not have.)
>>> 
>>> I mean... "No peripheral hardware support within the cpu ..."
>>> 
>>> Jon
>>
>>I guess you might be able to do something like the V-USB project (the
>>software-only device-side USB stack for AVR). Maybe you would want a
>>bit faster CPU (just because the host-side stuff is probably a bit more
>>complex?though it does have the advantage that a host doesn?t need to
>>always watch the wires for traffic the way a device does), and it would
>>not be USB compliant (because a compliant USB host must support at
>>least low speed *and* full speed, while a device only needs to support
>>one or the other, and you would probably only implement low speed), but
>>in the limited case of plugging in USB keyboards, it might work. At
>>least, you could probably get it to work with *most* keyboards.
>>
>>Chris
>
> Thanks, Chris. That doesn't say I can't do it, or that I
> necessarily can. But maybe. At least the door remains open,
> so far.
>

I guess you are going to be reading the full USB spec after all. :-)

I am not familiar with the physical signalling level as you don't need
that knowledge to write a USB device or host stack which uses a hardware
USB controller so I will comment on some other issues.

First, are the USB keyboards you can buy today still low-speed devices
or are they now full speed only devices ?

Given what I currently know, I think you can justify exploring further
the idea of a software only low speed USB host, but I don't see how you
can implement a full speed host in software on the types of MCUs you
are talking about without some hardware support.

I've also been thinking about what steps are _required_ from the device
enumeration sequence after it's attached to a host. I think it may be
possible to drop the reading of the descriptors; there's certainly nothing
in my device stack which _requires_ the descriptors to be read before the
next stage can complete.

The values in the descriptors (for example, the configuration index) are
required in later steps of the sequence, but if your host stack already
has prior knowledge of the values, I don't see why it would need to read
them from the keyboard's descriptors.

However, the other steps are all required. For example, during reset I
configure endpoint 0, setting the address is required before you can
set a configuration and the set configuration stage (at least in my stack)
is where you run down the endpoint descriptors and configure the
application level (ie: HID in your case) endpoints as required.

Simon.

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

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#10875 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Thu, 20 Dec 2012 14:13:11 +0000 (UTC), Simon Clubley
<clubley@remove_me.eisner.decus.org-Earth.UFP> wrote:

>On 2012-12-19, Jon Kirwan <jonk@infinitefactors.org> wrote:
>> On Wed, 19 Dec 2012 18:42:16 -0800, Christopher Head
>><chead@is.invalid> wrote:
>>
>>>On Wed, 19 Dec 2012 10:44:43 -0800
>>>Jon Kirwan <jonk@infinitefactors.org> wrote:
>>>
>>>> On Wed, 19 Dec 2012 10:39:30 -0800, I wrote:
>>>> 
>>>> >No hardware support is used if I
>>>> >understand what I've read (I may not have.)
>>>> 
>>>> I mean... "No peripheral hardware support within the cpu ..."
>>>> 
>>>> Jon
>>>
>>>I guess you might be able to do something like the V-USB project (the
>>>software-only device-side USB stack for AVR). Maybe you would want a
>>>bit faster CPU (just because the host-side stuff is probably a bit more
>>>complex?though it does have the advantage that a host doesn?t need to
>>>always watch the wires for traffic the way a device does), and it would
>>>not be USB compliant (because a compliant USB host must support at
>>>least low speed *and* full speed, while a device only needs to support
>>>one or the other, and you would probably only implement low speed), but
>>>in the limited case of plugging in USB keyboards, it might work. At
>>>least, you could probably get it to work with *most* keyboards.
>>>
>>>Chris
>>
>> Thanks, Chris. That doesn't say I can't do it, or that I
>> necessarily can. But maybe. At least the door remains open,
>> so far.
>
>I guess you are going to be reading the full USB spec after all. :-)
>
>I am not familiar with the physical signalling level as you don't need
>that knowledge to write a USB device or host stack which uses a hardware
>USB controller so I will comment on some other issues.
>
>First, are the USB keyboards you can buy today still low-speed devices
>or are they now full speed only devices ?
>
>Given what I currently know, I think you can justify exploring further
>the idea of a software only low speed USB host, but I don't see how you
>can implement a full speed host in software on the types of MCUs you
>are talking about without some hardware support.

I believe they are low speed, HID. I agree completely that a
full speed host would be ... difficult. ;)

>I've also been thinking about what steps are _required_ from the device
>enumeration sequence after it's attached to a host. I think it may be
>possible to drop the reading of the descriptors; there's certainly nothing
>in my device stack which _requires_ the descriptors to be read before the
>next stage can complete.
>
>The values in the descriptors (for example, the configuration index) are
>required in later steps of the sequence, but if your host stack already
>has prior knowledge of the values, I don't see why it would need to read
>them from the keyboard's descriptors.

Understood. Point taken.

>However, the other steps are all required. For example, during reset I
>configure endpoint 0, setting the address is required before you can
>set a configuration and the set configuration stage (at least in my stack)
>is where you run down the endpoint descriptors and configure the
>application level (ie: HID in your case) endpoints as required.

I'll need to understand more of the spec and think a bit to
see what can be done here, I suspect. But I'm keeping all
this for later and, as with Chris, I very much appreciate
these comments. They will most certainly help focus my
attention better.

Thanks,
Jon

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#10901 — 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> 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.
>

Look at msp430f550x series.  IIRC the cheapest one has 
has TI suggested retail price 1.6$.  However, RAM
is much bigger than 512 bytes: all in the series have
2kB RAM for USB controller and 4kB data RAM.

-- 
                              Waldek Hebisch
hebisch@math.uni.wroc.pl 

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#10907 — 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> wrote:
> 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 $2.
> > 
> > Any chance? It is just a keyboard, after all.
> >
> 
> Look at msp430f550x series.  IIRC the cheapest one has 
> has TI suggested retail price 1.6$.  However, RAM
> is much bigger than 512 bytes: all in the series have
> 2kB RAM for USB controller and 4kB data RAM.
> 

Oops, msp430f550x is device only...

-- 
                              Waldek Hebisch
hebisch@math.uni.wroc.pl 

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#10908 — Re: Writing a USB device stack, was: Re: USB CDC ACM, was: Re: serial host-to-device communication in amateur designs

On Mon, 24 Dec 2012 15:45:45 +0000 (UTC), Waldek Hebisch
<hebisch@math.uni.wroc.pl> wrote:

>Waldek Hebisch <hebisch@math.uni.wroc.pl> wrote:
>> 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 $2.
>> > 
>> > Any chance? It is just a keyboard, after all.
>> 
>> Look at msp430f550x series.  IIRC the cheapest one has 
>> has TI suggested retail price 1.6$.  However, RAM
>> is much bigger than 512 bytes: all in the series have
>> 2kB RAM for USB controller and 4kB data RAM.
>
>Oops, msp430f550x is device only...

Thanks for checking on it. I was about to do that, today.

Jon

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#10872 — Re: serial host-to-device communication in amateur designs

On Sun, 16 Dec 2012 13:46:10 -0800, Jon Kirwan <jonk@infinitefactors.org> wrote:
> On Sun, 16 Dec 2012 21:00:41 +0700, Ivan Shmakov
><oneingray@gmail.com> wrote:
...several attributions lost...

   [...]

>> > To OP: For a cheap hobbyist one-off with USB connection I'll probably
>> > just grab an MSP430 LaunchPad off the shelf if the application idea
>> > fits.  It's already got connectors for a daughterboard, the cpu is
>> > socketed, comes with two cpus,
>>
>>	Somehow, I was unable to find out what exactly comes with this
>>	board?  But given the price, it indeed looks like a nice thing
>>	to have.
>
> You get:
> •    Nice box
> •    Paperwork
> •    ½ m USB cable
> •    Microcrystal MS3V-T1R tuning fork 32.768kHz crystal
> •    MSP430G2231 cpu, DIP
> •    MSP430G2211 cpu, DIP

With the currently-shipping v1.5 LaunchPad boards you get:

  MSP430G2553: 16Kb FLASH, 512b RAM, UART/SPI/I2C, 8ch/10bit ADC,
      comparator, touch-sense enabled I/Os. 
  MSP430G2452:  8Kb FLASH, 256b RAM, UART/SPI/I2C, 8ch/10bit ADC,
      comparator, touch-sense enabled I/Os. 

> •    LaunchPad board, which includes a USB to host section
> and a developer section with socket for cpu, two pushbuttons
> for user use (as well as reset), two leds, one green, one
> red, jumpers for enabling and disabling features, a special
> interface for using the board to program target boards as
> well (6-pin EZ430 connector), a power connector for your use
> to run the board, and of course a USB connector
> •    four headers for daughter card extensions, 2 male-female
> and 2 male-male

Plus two compiler/IDE suites plus the MSP430 port of gcc.

As for USB, I'm aware of one effort in this direction:

  USB v1.1 support on the MSP430 Launchpad
  http://www.43oh.com/2012/12/usb-v1-1-support-on-the-msp430-launchpad/

Hope this helps...


Frank McKenney
-- 
  Generations of students in the social sciences have been exposed
  to entertaining lectures that point out how dumb everyone else
  is, constantly wandering off the path of logic and getting lost
  in the fog of intuition.  Yet logical norms are blind to content
  and culture, ignoring evolved capacities and environmental
  structure.  Often what looks like a reasoning error from a
  purely logical perspective turns out to be a highly intelligent
  social judgment in the real world.  Good intuitions must go
  beyond the information given, and therefore, beyond logic.
          -- Gerd Gigerenzer / Gut Feelings: The Intelligence
                               of the Unconscious.
-- 
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney aatt mindspring ddoott com

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#10874 — Re: serial host-to-device communication in amateur designs

On Thu, 20 Dec 2012 10:00:28 -0600, Frnak McKenney
<frnak@far.from.the.madding.crowd.com> wrote:

>On Sun, 16 Dec 2012 13:46:10 -0800, Jon Kirwan <jonk@infinitefactors.org> wrote:
>> On Sun, 16 Dec 2012 21:00:41 +0700, Ivan Shmakov
>><oneingray@gmail.com> wrote:
>...several attributions lost...
>
>   [...]
>
>>> > To OP: For a cheap hobbyist one-off with USB connection I'll probably
>>> > just grab an MSP430 LaunchPad off the shelf if the application idea
>>> > fits.  It's already got connectors for a daughterboard, the cpu is
>>> > socketed, comes with two cpus,
>>>
>>>	Somehow, I was unable to find out what exactly comes with this
>>>	board?  But given the price, it indeed looks like a nice thing
>>>	to have.
>>
>> You get:
>> •    Nice box
>> •    Paperwork
>> •    ½ m USB cable
>> •    Microcrystal MS3V-T1R tuning fork 32.768kHz crystal
>> •    MSP430G2231 cpu, DIP
>> •    MSP430G2211 cpu, DIP
>
>With the currently-shipping v1.5 LaunchPad boards you get:
>
>  MSP430G2553: 16Kb FLASH, 512b RAM, UART/SPI/I2C, 8ch/10bit ADC,
>      comparator, touch-sense enabled I/Os. 
>  MSP430G2452:  8Kb FLASH, 256b RAM, UART/SPI/I2C, 8ch/10bit ADC,
>      comparator, touch-sense enabled I/Os. 

Thanks for the correction. I do remember, now that you bring
it up, that the CPUs had changed. I just don't have any to
remind me about it. Thanks!

>> •    LaunchPad board, which includes a USB to host section
>> and a developer section with socket for cpu, two pushbuttons
>> for user use (as well as reset), two leds, one green, one
>> red, jumpers for enabling and disabling features, a special
>> interface for using the board to program target boards as
>> well (6-pin EZ430 connector), a power connector for your use
>> to run the board, and of course a USB connector
>> •    four headers for daughter card extensions, 2 male-female
>> and 2 male-male
>
>Plus two compiler/IDE suites plus the MSP430 port of gcc.

Yes. I've been having almost nothing but trouble with IAR's
on my "clean" install of Win7 Ultimate 64-bit, though. I
don't know what the problem is, but I've tried it with many
different LaunchPads and different USB connectors (the
motherboard has a LOT of them) and I also tried doing it with
the XP 32-bit VM from Microsoft running underneath without
any better success (I didn't expect that to work, anyway.) On
the same system, CCS does just fine. Odd thing there, _if_
both are using the same DLL (which maybe they are not.)

On a Thinkpad laptop running Win7 Professional, though, IAR
works great. And on all my other machines, just fine. But
they aren't 64-bit installs.

>As for USB, I'm aware of one effort in this direction:
>
>  USB v1.1 support on the MSP430 Launchpad
>  http://www.43oh.com/2012/12/usb-v1-1-support-on-the-msp430-launchpad/
>
>Hope this helps...

Oh, yes. Added to my USB favorites folder. I'll look it over.
Thanks.

Jon

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#10876 — Re: serial host-to-device communication in amateur designs

On Thu, 20 Dec 2012 11:54:19 -0800
Jon Kirwan <jonk@infinitefactors.org> wrote:

> On Thu, 20 Dec 2012 10:00:28 -0600, Frnak McKenney
> <frnak@far.from.the.madding.crowd.com> wrote:
> 
> >Plus two compiler/IDE suites plus the MSP430 port of gcc.
> 
> Yes. I've been having almost nothing but trouble with IAR's
> on my "clean" install of Win7 Ultimate 64-bit, though. I
> don't know what the problem is, but I've tried it with many
> different LaunchPads and different USB connectors (the
> motherboard has a LOT of them) and I also tried doing it with
> the XP 32-bit VM from Microsoft running underneath without
> any better success (I didn't expect that to work, anyway.) On
> the same system, CCS does just fine. Odd thing there, _if_
> both are using the same DLL (which maybe they are not.)
> 
> On a Thinkpad laptop running Win7 Professional, though, IAR
> works great. And on all my other machines, just fine. But
> they aren't 64-bit installs.
> 

I haven't tried it under Windows, but I just used the Linux version of
mspgcc for a personal project, and was really impressed by how clean
and easy it wound up being.  You also need mspdebug if you're going to
work with a LaunchPad, but once I got them installed things just did
what they were supposed to.

-- 
Rob Gaddi, Highland Technology -- www.highlandtechnology.com
Email address domain is currently out of order.  See above to fix.

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#10877 — Re: serial host-to-device communication in amateur designs

On Thu, 20 Dec 2012 12:01:39 -0800, Rob Gaddi
<rgaddi@technologyhighland.invalid> wrote:

>On Thu, 20 Dec 2012 11:54:19 -0800
>Jon Kirwan <jonk@infinitefactors.org> wrote:
>
>> On Thu, 20 Dec 2012 10:00:28 -0600, Frnak McKenney
>> <frnak@far.from.the.madding.crowd.com> wrote:
>> 
>> >Plus two compiler/IDE suites plus the MSP430 port of gcc.
>> 
>> Yes. I've been having almost nothing but trouble with IAR's
>> on my "clean" install of Win7 Ultimate 64-bit, though. I
>> don't know what the problem is, but I've tried it with many
>> different LaunchPads and different USB connectors (the
>> motherboard has a LOT of them) and I also tried doing it with
>> the XP 32-bit VM from Microsoft running underneath without
>> any better success (I didn't expect that to work, anyway.) On
>> the same system, CCS does just fine. Odd thing there, _if_
>> both are using the same DLL (which maybe they are not.)
>> 
>> On a Thinkpad laptop running Win7 Professional, though, IAR
>> works great. And on all my other machines, just fine. But
>> they aren't 64-bit installs.
>
>I haven't tried it under Windows, but I just used the Linux version of
>mspgcc for a personal project, and was really impressed by how clean
>and easy it wound up being.  You also need mspdebug if you're going to
>work with a LaunchPad, but once I got them installed things just did
>what they were supposed to.

Wonderful to hear. That was next on my list to try out, as
well. Good news!

Thanks,
Jon

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#10809 — Re: serial host-to-device communication in amateur designs

On 2012-12-14, Ivan Shmakov <oneingray@gmail.com> wrote:
>>>>>> Robert Wessel <robertwessel2@yahoo.com> writes:
>
> [...]
>
> > And frankly the use of RS-232/async ports should not be a first
> > choice these days.
>
> 	Given the intended application, I tend to agree -- the use of
> 	USB would probably simplify the things there a lot.
>
> 	Unfortunately, I'm yet to find a really cheap MCU (8-, 32-, or
> 	perhaps even 16-bit) with an on-chip USB.  (V-USB doesn't seem
> 	to fit well, for its CDC-ACM capability is necessarily a hack.)
> 	The best I've found so far are some STM32's for under $4.  I'd
> 	like to see if there could be anything else at half that price.
>

I am assuming you want USB device only. If you want USB host as well,
try looking at the PIC32MX range to see if it's something that would
match your requirements.

Your previous postings imply that you are doing hobbyist type work and
you don't say what packaging you need the device in so as much as it
pains me :-), I am going to point you to the PIC18F range if you want
it in PDIP.

Start by looking at the PIC18F14K50. It's quite a limited device so
you may need to look at the other options in the PIC18F range to see
which of them also support USB device.

> 	(Though USB identifiers may become an issue.  They provide one
> 	allowing for relatively unrestricted use with V-USB, but I don't
> 	know what's the current practice for the MCU's with hardware USB
> 	ports.)
>

Since I only use them for my own projects, I just make them up. Since
no one else uses my embedded code, I also don't know what the current
practice is short of having to pay for formally assigned identifiers.

In the past I have heard of some manufacturers allowing you to use
identifiers within a subset of the range assigned to the manufacturer,
but I don't know what the current policy is.

Simon.

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

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#10810 — Re: serial host-to-device communication in amateur designs

>>>>> Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> writes:
>>>>> On 2012-12-14, Ivan Shmakov <oneingray@gmail.com> wrote:

[...]

 >> Unfortunately, I'm yet to find a really cheap MCU (8-, 32-, or
 >> perhaps even 16-bit) with an on-chip USB.  (V-USB doesn't seem to
 >> fit well, for its CDC-ACM capability is necessarily a hack.)  The
 >> best I've found so far are some STM32's for under $4.  I'd like to
 >> see if there could be anything else at half that price.

 > I am assuming you want USB device only.

	Yes.

[...]

 > Your previous postings imply that you are doing hobbyist type work
 > and you don't say what packaging you need the device in so as much as
 > it pains me :-), I am going to point you to the PIC18F range if you
 > want it in PDIP.

	My guess is that anything with 0.8 mm or larger spacing will be
	just fine.  0.5 mm pitch feels a bit too fine to tackle for an
	amateur, but I'm yet to try it myself.

 > Start by looking at the PIC18F14K50.  It's quite a limited device so
 > you may need to look at the other options in the PIC18F range to see
 > which of them also support USB device.

	... As for the PIC's, given the sheer number of university
	courses built around these I've seen, I've always assumed
	there're something wrong with them.  (Some of their "weak
	points" were referenced in recent CAE postings, BTW.)

	Anyway, is there a reason I'd choose this particular MCU over,
	say, STM32F103C8 (other than the package, which is the troubling
	0.5 mm LQFP 48 for the latter, that is)?  As for the cost, it
	seems to be > $5 a piece for the former vs. < $3 for the latter
	(for the smaller orders, e. g., a dozen or so.)

 >> (Though USB identifiers may become an issue.  They provide one
 >> allowing for relatively unrestricted use with V-USB, but I don't
 >> know what's the current practice for the MCU's with hardware USB
 >> ports.)

 > Since I only use them for my own projects, I just make them up.

	Unfortunately, my ultimate intent is to share the designs with
	the community, and using a "made-up" identifiers doesn't seem
	like a particularly good example to teach on.

[...]

-- 
FSF associate member #7257

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#10813 — Re: serial host-to-device communication in amateur designs

On 2012-12-14, Ivan Shmakov <oneingray@gmail.com> wrote:
>>>>>> Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> writes:
>>>>>> On 2012-12-14, Ivan Shmakov <oneingray@gmail.com> wrote:
>
> [...]
>
> > Your previous postings imply that you are doing hobbyist type work
> > and you don't say what packaging you need the device in so as much as
> > it pains me :-), I am going to point you to the PIC18F range if you
> > want it in PDIP.
>
> 	My guess is that anything with 0.8 mm or larger spacing will be
> 	just fine.  0.5 mm pitch feels a bit too fine to tackle for an
> 	amateur, but I'm yet to try it myself.
>
> > Start by looking at the PIC18F14K50.  It's quite a limited device so
> > you may need to look at the other options in the PIC18F range to see
> > which of them also support USB device.
>
> 	... As for the PIC's, given the sheer number of university
> 	courses built around these I've seen, I've always assumed
> 	there're something wrong with them.  (Some of their "weak
> 	points" were referenced in recent CAE postings, BTW.)
>

Yes, including by myself. :-) They do have a lousy architecture, but
they are available in packages I am comfortable working with and they
have USB device in those same packages which the other MCU architectures
I prefer do not.

> 	Anyway, is there a reason I'd choose this particular MCU over,
> 	say, STM32F103C8 (other than the package, which is the troubling
> 	0.5 mm LQFP 48 for the latter, that is)?  As for the cost, it
> 	seems to be > $5 a piece for the former vs. < $3 for the latter
> 	(for the smaller orders, e. g., a dozen or so.)
>

If you are comfortable working at something smaller than PDIP, then
I cannot think of any reason to consider the 8-bit PICs in your case.

BTW, at Farnell in the UK, they are charging just over 2 UKP per unit
(well under 4 US$ at current exchange rates) for the PIC18F14K50 and I
have always considered Farnell to be a bit more expensive than some
others based on the prices I have paid for other products.

The AT90USB162-16AU comes in a TQFP 0.8mm pitch package according to
Atmel's summary PDF; the Farnell UK price seems reasonable at qty 10,
but given what you have said above, I don't know what price your
suppliers would charge for them however.

Simon.

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

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#10820 — Re: serial host-to-device communication in amateur designs

>>>>> Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> writes:

[...]

 > The AT90USB162-16AU comes in a TQFP 0.8mm pitch package according to
 > Atmel's summary PDF; the Farnell UK price seems reasonable at qty 10,

	As it seems, ATmega8U2/TQFP is available at the same price.  Any
	specific reason to prefer one over the other?

 > but given what you have said above, I don't know what price your
 > suppliers would charge for them however.

	Well, Farnell may turn to be suitable, but I'm yet to check
	their shipping conditions.

-- 
FSF associate member #7257

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#10832 — Re: serial host-to-device communication in amateur designs

On 2012-12-14, Ivan Shmakov <oneingray@gmail.com> wrote:
>>>>>> Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> writes:
>
> > The AT90USB162-16AU comes in a TQFP 0.8mm pitch package according to
> > Atmel's summary PDF; the Farnell UK price seems reasonable at qty 10,
>
> 	As it seems, ATmega8U2/TQFP is available at the same price.  Any
> 	specific reason to prefer one over the other?
>

Sorry, but I have no experience with the USB capable AVRs. I only know
about them because I have seen them mentioned while working with other
AVRs.

Simon.

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

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