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Even just going through the terminology and getting the visuals of how the various parts of the protocol relate has been extremely helpful.

Iron

I wish I could have had this webinar series a year ago when I got thrown into designing embedded USB into a new system.  Fortunately I had source code from another engineer's design that I could refer to, but a lot of it I had to develop through trial and error.  Not the easist way to go, that's for sure!

Iron

thank you Christian,

Iron

remote wireless sensors for industrial apps

Iron

hardware design engineer

Iron

Thank you Christian for sharing knowledge.

Iron

based on the first two days today should be great

So sorry I missed the lecture real time. The slide #s, Keep up the good work and thanks for everything

Rodney B. Rutherford

Iron

AcohenJr

Great lecture

Interrupt for my projects

Iron

Excellent Topic! Thanks!

Iron

Very good lecture - information overload... Wow!!!

Iron

wow, that's a lot to digest in less than an hour. I'll come back later to review.

Thanks Chrtistian, see all tomorrow.

Iron

Good to have access to the recorded sessions.

Iron

I've missed the live lecture today...

Iron

Thank you! See you tomorrow!

@Christian Thanks, see you tomorrow!

Iron

Merci for the calculation...The device use a STM32F103 32bit controller.  I think the float are defined at 32bit (4 bytes).  I have to read more on the IAR EWARM compiler I am using...  This means I could theoretically push it to 64 devices...

Now, the trick is to turn the payload into a HID payload.  And convert it back on the host.

 

Iron

Thunderbolt vs USB3.0

For an embedded system, assuming you have the resources to use these protocol capabilities, I would go the USB 3.0 because it is a more general standard.

If it is for your personal use, it all depends what you want to use a peripherals. For an external Mass Storage, I would go with Thunderbolt just because it would save me time when I want to do a backup!

here I am, better late than never

Iron

Can you achieve a overall sampling rate of 100Hz for up to 32 USB FS devices connected, when the payload is 4 floats per device. Could this be achieve with HID/Joystick type class, or should I go directly with a custom class??

 

We will have to do the math. First, HID is the right class to use, because it is peioritized by the Host.

(Your 4 floats are 64 bits each? this would mean 32 bytes per transfer)

Second, let's look at the Full Spee table for Interrupt transfer using 32 bytes transfer and see the maximum throughput.

 

At 100Hz, that would mean once every 10 frames. Or stated otherwise, that would mean you can server 3.2 device per frame and have covers the 32 devices in 10 frames.

An example of a simple USB communication would be helpful. Like from a mouse. Also, Christian, I'm interested in which USB protocal analyzers are available for low cost, and what is gained from a more expensive analyzer.

 

Tomorrow, I will give an example of how a Device is recognized by  a Host and the complete enumeration process.

 

Low cost, good Price/Performance ratio analysers woudl be products from TotalPhase.

 

Ellisys protocol analysers are a bit more expensive but have better presentation of information. Ellisys also provides a USB Generator that is very useful when you want to test a Host as we will see Friday.

 

Can you achieve a overall sampling rate of 100Hz for up to 32 USB FS devices connected, when the payload is 4 floats per device.  Could this be achieve with HID/Joystick type class, or should I go directly with a custom class??

Iron

It would be nice to provide a few examples from start to finish how a USB packet works with a real device.

This is what a protocol analyzer will bring you.

This is more difficult with the format of these webinars. WHen I do hands-on classes at Design East or Design West, this is exactly what we do. Attendees have access to hardware and protocol analyzers and we look at the various transfer types and USB Classes.

This may not be the right place to ask the question, but I like to know your take on Thunderbolt vs USB3.0. 

Iron

An example of a simple USB communication would be helpful. Like from a mouse. Also, Christian, I'm interested in which USB protocal analyzers are available for low cost, and what is gained from a more expensive analyzer.

Iron

It appears from slide 35 that it is possible to have multiple interface types.

Yes, and we will see this tomorrow with the Descriptors, the Interfaces and the Classes.

Christian: About the ZLP; I understand is is only true for N*max_size. ITs good to have that confirmed because I could not find the text in the standard that stated so ... for DATA transfers. I found the text explicit for CONTROL transfers.

 

Thanks

Iron

The requirement to have a vendor ID assigned to products is very important.

 

We will see this tomorrow.

Thanks. We have an RFID reader acting as a wedge but would like to add the ability to set parameters in the reader via a host application.

Iron

I'm here to learn about designing with USB in general. I'm also interested in isochronous data transfers for multiple video streams, with some way to know when each image was captured by the cameras. Thanks for your presentation.

Iron

ZLP is only used if the data you have to transfer is an integer multiple of the maximum packet size.

It appears possible to define a set of end-points as an HID interface and another set to cdc.

 

Yes

Hi Christian: I am trying to understand the bandwidth calculation. Is there a link with more details? I just need to walk through one computation to understand the rest. Thanks!:

The 2 previous slides to the tables give you how to interpret the tables. If you feel this in not enough, the only other reference I can think of is the USB spec itself.

I am using off-the-shelf code. Most of my time is spent on the descriptor tables.

Iron

amazing what such a small device entails. thanks:

This is exactly why I suggest that if you want to implement USB in a product, please use Commerical of the shelf components and software stack. Don't reinvent the wheel. USB is plug-and-play, but only because a lot of people spend a lot of time doing all the is required to make this happen.

Hi Christian: I am trying to understand the bandwidth calculation. Is there a link with more details? I just need to walk through one computation to understand the rest. Thanks!

 

Iron

It appears possible to define a set of end-points as an HID interface and another set to cdc.

Iron

The ZLP is used for all transfers? I saw that it was so in Control packets but I could not find that text for the data transfers. Its good to get that confirmed because I have been assuming it is true.

 

Iron

A colleague recommended the TotalPhase Beagle USB analyzer.  I have model 480 (USB2.0 capable).  Easy to use.

Iron

TotalPhase proudcts are very good Price/Performance protocol analyser. My second choice would be Ellisys. A bit more expensivce. Finally, you will find the Lecroy and Tecktronix level analyzers.

amazing what such a small device entails. thanks Christen.

When an application sends N bytes how does the peer know when the entire application packet has been received?

Good question!

As you saw from the packets, there are not "length of transfer" So, USB uses what is called a Zero Length Packet «)ZLP). If a packet received is smaller than the Maximium packet size for the transfer  mode at a certain speed, than it knows that is was the last packet. Otherwise, the transmitter has to send a ZLP to signel the end of the transfer.

 

@Christian  What USB Protocol Analyzer(s) would you recommend?

Iron

I'm working on a vehicle infotainment system, using liliput 7" touchscreen display and small android ARM device.  I'm having difficulty interfacing the HDMI\USB touch screen touches with Android.  The kernal must not support it, though it daisplays on screen great.  I don't think I need to understand the USB aspect, but this helps when I get to the Arduino portion to support a hub and digital FM reciever as well as understanding integrating GPS into it.

Platinum
The requirement to have a vendor ID assigned to products is very important.

we designed an interface that connects a PC with USB to an indstrial network (CAN) so I'm interested in the max transfer rates.

Thanks Christian

Iron

I have used the CATC / LeCroy USB analyzers with great success.  They were expensive but they worked very well.

Iron

Thank you this presentation is awesome!

Iron

It appears from slide 35 that it is possible to have multiple interface types.

Iron

Good information in the slides.  I missed yesterday, and just got back now.

Iron

Good presentation. It would be nice to provide a few examples from start to finish how a USB packet works with a real device.

Iron

remote wireless sensors for industrial control (temp. Pressure. flow, ) also industrial alarms

 

Iron

How do I determine how many endpoints I need? All the endpoints go through the same wires, right? So the more endpoints I have, the less bandwidth each one will get. Can I just have two endpoints, one for control (mandatory), and one for data?

 

Iron
Thanks Christian and Jen !

@Christian: WOW! That was a fabulous overview of the USB software architecture's lower layers. Thank you!

Iron

JVonHatten; I do not think so. USB data packets are sent in fixed sizes, say 64 bytes

How do you know when the end of the application packet is received? This is what I understand but have no confirmation. If you get a packet that is less than 64 bytes, end of sequence. If it is 64 bytes, there is more to come. If the application packet is 64*N where N is an integer, one will receive a 0-byte packet.

This is true for Control packets. How about the data transfers?

 

Iron

Thanks Christian and Jennifer!

Iron

I'm a software engineer working on metrological products.

Iron

Agree that Beagle USB analyzer is very good.

Iron

Good presentation, Thanks.

 

Iron

Great presentation!  Thank you so much, Christian!

Iron

thanks that was alot of great info.

Iron

Thank you @Jennifer & @Christian

Iron

Thank you Christian and Jennifer.

Iron

Working on an HMI for industrial controls.

Iron

Thank you Christian.

The information is very helpful!

Iron

Thanks Christian and Jennifer!

Iron

Awesome presentation!! Thank you!

Iron

Wow. Fantastic amount of data presented. I appreciate the depth and detail presented as well as the good slides that can and will be used for later reference. Thanks!

Wow, this is a great presentation. Lots of reference material.

Merci Christian!

Iron

wow, lost of information, thanks

Yes, USB protocol analyzer is a must. We use the Beagle5000 from TotalPhase. Good bang for the buck.

 

Iron

This presentation is great! The ammount of information presented in slides helps a lot!

Iron

@Jennifer   I'm lovin' it!!   Thank you and Christian, and all attendees!!

Another excellent presentation

Iron

Is Serial over USB using Interrupt?

Iron

Glad to see everyone is enjoying the presentation! Please join our Digi-Key Continuing Education Center LinkedIn Group at http://linkd.in/yoNGeY

My audio has been fine...

 

Iron

gyannea -- I am assuming it states how many bytes there are in the header

Iron

Yes this series has in general been great

Iron

Having a lot more trouble with the audio dropping out today... when every second counts.

Iron

When an application sends N bytes how does the peer know when the entire application packet has been received?

 

Iron

Halfway through and I'm thinking this (entire) presentation is in the top 5 

Quantity and Quality of information are great.

Yes it's too much and too fast for the time frame -- but I'll read everything again later -- several times.

Iron

problably iso + interrupt

Iron

No specific app yet...

Iron

we will use the bulk transfer type

 

Iron

Sensor Drivers of various types -- plus other projects

Iron

@Jennifer - at the speed of this presentation, I suspect many are not watching the live chat

Iron

Embedded firmware developer, entertainment lighting & lighting control systems

Iron

Irrigation system controllers and RTUs.

Iron

Hardware engineer, test system design

Iron

Test fixture development

Iron

Middleware Messaging Router

Iron

test system with a large number of sensors and controls,

Many of which that used to use rs-232 are now usb.

Iron

Embedded SW programmer working on ARM Cortex M projects

@Jennifer- localized and remote data monitoring

Iron

nfc - contactless payments

Iron

what about lost packets in even numbers?

 

Iron

Now that we know your discipline - tell us, what projects are you currently working on?

 

Project Management -- So I really don't get to specialize -- I have to be able to work with HW/SW/FW plus the com protocols.

Iron

system architect, s/w engineer

Iron

Chip designer / SW engineer.

Iron

Embedded Software Engineer for R&D

 

Iron

Embedded Design Engineer for R & D

Iron

IRAD Engr, Embedded, Software & Hardware

 

Iron

I am a firmware engineer.

Iron

thank you for the slide numbers

Iron

I'm an embedded systems designer. Both Hardware and Sofware.

Iron

Where does the data go in the packet?

Iron

Product development EE, HW & FW

Iron

AssAssistive Technology Specialist

Mark Bresler

IC design and verifcation.

Electrical Engineering.  Embedded systems.

Iron

Welcome everyone! We'd like to know - what is your discipline?

We are using Storage for our Host, and would like to use Communication for our Device

Iron

Hello from Scottsdale, AZ

Iron

getlive chat by logging in

 

Iron

You have to login to view the chat window

Iron

audio? okay there it is.

Iron

How do you get into the Live Chat?

Now comes the good stuff, data structures. Let the games begin.

Hello from Costa Mesa, CA

Iron

Good afternoon From Fredericksburg, VA

 

Hello from Austin, TX

Jim Hughen

Iron

Hello from Albuquerque.

Iron

Hey RoboPaint. I was thinking of relocating to Tulsa til I heard that last summer was triple digits for nearly 3 months stright. My brother lives there and said it was painful to venture outdoors.

Iron

I check in early just to make sure every thing is working.

Iron

Just waiting for the audio bar

 

Iron

I log in a bit early just to see if the link is working...

Iron

Welcome from Colorado Springs, CO

Iron

So are all of you just really punctual or is the Starbucks thing the real motivation.......

Iron

Hello from Cedar Park, TX again...

Iron

Good day from Massachusetts. 

Iron

Hello from Scottsdale,AZ

Iron

Hello From Millington Michigan.

Iron

A balmy 32 degF in Minneapolis today...

Iron

...and I'm thinking I wanna move south, where it's warmer.   :)  {Time for me to sit back and be quiet, prepare for the lecture.}    I enjoyed visiting with everyone.  :)

fwjava - let me check in with the site admin to see if something like that is a possibility.

@JoeFromOzarks That's the advantage of suffering the cold by living in Vermont. You just need a good horse to get to Canada for your Twinkies fix.

Iron

Mercy case?  I kin git mah fix o' Hostess?   Lemme call the airport... maybe they'll let hillbillies on planes now.   :)

@Jennifer It would be nice if we did have a way to contact other class participants.  Maybe someway to activate (with permission of course) the users email during a live class session.  There have been a couple people I would have liked to contact but not necessary through the chat window.

Iron

@Lawson No worries, it worked, and the slides are readable, which mine weren't.

Iron

@EdB_Vt You're welcome!  Sorry about the shady upload site.  Didn't know what else to use.  YouSendIt requires an email address...

Iron

Joe: Had to Look up STEM -- cool man.

Yeah Real Sugar in the Twinkies and Cup Cakes -- and we still have plastic wrap and bags here -- for a few months stiill...

We have a special refugee program for Hostess Addicts. It's recognized as a mercy case by our government. rotflmao

 

 

Iron

@JoeFromOzarks It's all good!

Iron

@Lawson - Thanks again for the PDF slides today. Yesterday I clicked on the button that asked to download the executable - which I didn't do of course. Then I found the other button that just downloads the pdf. I did a virus scan in case the site added something nefarious (found nothing). I already checked out tomorrow's slide deck, and it "plays nice" with the PowerPoint viewers I have.

Iron

Oops, copy & paste results in duplicate posts, sorry. 

"gotta do somethin' fer a livin'."   <- Josie Wales.   :)  

@Lawson, the page numbers are on each slide today.  I get to sit back and enjoy the lecture.   :)   {Yesterday I felt like I was calling bingo...}   :)

Phd in S.T.E.M. education.  (I'm retired, "gotta do somethin' fer a livin'.")   Canada uses real sugar in their Hostess treats?  :)

Hi All From Rainy California

Iron

from the sunny south, good morning to all.

Iron

PS: We can supply Hostess Twinkies and Cup Cakes from Canada -- Just sayin'

Iron

Joe: Post grad eh? Working on what -- if I may be so bold. (Not specific -- just generally.)

Iron

I love my cherry pie and ice cream!   :)   {And Hostess Cub Cakes, but we'll leave THAT alone!}   :)

Hello from Snowy SE Lake Simcoe in Ontario, Canada.  I just looked out the window! ARGGGHHH!

Iron

No billing.   :)   I truly enjoy these classes!  (I'm also working on post grad, those classes are work!)   Cherry pie and ice cream (with Pepsi) was my payment yesterday.   :)

@JoeFromOzarks Yeah, and with 57 slides today it would be even more hectic!  As long as Christian calls out the slide numbers we should be good...

Iron

I think Joe would settle for a home cooked (sour) Cheery Pie and some ice cream -- with coffee. That owould be a good deal if he will do it. I was hungry the rest of the day thinking about that...

 

Iron

@bitbanger55 Yeah, sorry about that.  I didn't have a good way to get the file to EdB_Vt so I just grabbed the first Google hit for upload sites.  Didn't figure people would want to post email addresses on here...

Iron

Thanks again JoeFromOzarks - I'll let you know where to send the bill for your fee! =)

@Lawson, the page numbers are on each slide today.  I get to sit back and enjoy the lecture.   :)   {Yesterday I felt like I was calling bingo...}   :)

@Lawson: will do. Adware, what a nuisance.

@JoeFromOzarks Howdy!  You up for calling out slide numbers again today?!  :D

Iron

@bitbanger55  I think maybe you're clicking on the wrong download button.  There seems to be an advertisement with a download button above the real download button.  I don't see this on Firefox b/c I run AdBlock Plus.  I just checked with IE and there are 2 separate download buttons.  One is for some lame download manager.  Try the one closer to the bottom of the page.

Iron
Post from chrome browser on iPad test
Post from iOS iPad as a test.

Hello from Chatsworth, CA where it is cloudy.

Iron

Howdy again from Fort Worth, TX

Iron

Thank you for the page numbers on the bottom of the slides!!   :)   'Bout killed me yesterday.   (I enjoyed helping out.)   :)

@Lawson: File download from www.2shared.com requires downloading and running an EXE on my Windows XP platforms. I assume unless you've already installed it from a previous lifetime, that is the case. Am I unique in this ? Anyone other than Lawson tried to download the PDF he made?

Good afternoon....made it today....

 

 

Iron

good afternoon, everyone

Iron

Been waiting for this one for a while.

Platinum

Hello, from a nice warm Arizona.

Platinum

Hello from Southern California.

Iron

Greetings from MA. Looking forward to the 57 slide marathon...

Iron

The slide decks for today and tomorrow are quite ambitious - upward of 50 today. Many are included for your reference, so we should be able to stick to our 30-40 minute time frame. See you at 2!

Hi everyone and welcome to the Digi-Key Continuing Education Center! We have added numbers to the slides for today's presentation, as well as to those for the Thursday and Friday classes.

@EdB_Vt - Windows 7, 64 bit

Iron

Don't have any of those PPT problem. I just have to ReFresh my Screen  (F5) 2 Min. before 2:00 PM (11:00 AM my time)

Iron

GOOD MORNING. Silicon Valley, CA

Rainy today. It's 58°F now and High of 61°F.

Iron

@JCheetham - I have the free Viewer, not full PowerPoint, also running on XP (if that matters)

Iron

V2 slides 18, 21, and 49 look ok on my PowerPoint 2007.

Iron

I wrote before downloading Today's Slide Deck - Thanks for the slide numbers! Looks ambitious - 57 slides! One for each Heinz variety.

I have the same problem from yesterday:
PowerPoint Viewer 2003: text in tables on slides 21, and 49 is too large
PowerPoint Viewer 2007: when I get to slide 18, get error "...encountered a problem and needs to close."
Not a problem on Monday, but then that deck doesn't seem to have the same type of tables.

Iron

Greetings - I second @rruther2's comment

Iron

The slides could use some numbers, please.

 

Iron


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