All right welcome back.
We just took a quick break there and of course all videos are potentially broken up into multiple parts
just for a time constraint.
So anyway now we're going to do is we're going to go over the USP to cereal you are.
All right so let's talk about this just in general if if so if you have no idea what I'm talking about
so you have some some context.
All right so you know years ago back in the you know the 80s in the 90s all PCs had serial ports.
And these are based on you know arist 2:32 is a standard arist 2:32 a very simple protocol it's got
a TXI and an R X line and a ground.
And then the serial data would clock out on ATX and R X it was at uncloaked protocol so basically it
would run at a certain speed and it was analog in nature so was plus and minus 12 volt.
And then there's digital TTL serial where it's a plus and plus 5 volts and zero volts represent the
the ones in the zeros.
So it's a little bit easier because the original arist 2:32 goes 12 volts plus and then minus 12 volts.
OK now.
So that was a really easy interface so three lines x R X and ground.
You could hook things up to your computer and get things done.
When USV came out Universal Serial Bus they got rid of the simple interface.
Now you can still get PCs and you can surely buy serial ports for example you can just go here.
Go to Google and say a serial port card PC right.
And or you can just go to Amazon and search so you can see just a bunch of things come up here of Dell
Dell DELL.
Not a big fan of that but you know Newegg.
And so here's a little car that has two little serial ports on it.
Real simple just plugs into a slot on your PC.
This is a PCI and it's $19 and then now you can do cereal.
All right.
OK.
But if you've got a laptop or a newer PC you're not going to have that.
All right.
So what's happened over over the past you know few years here I don't know maybe 10 years companies
have come out with us be the devices that create a standard digital TTL version of cereal so you can
take a U.S. v port you can connect it to your device and then the device then gives you out serial T-Rex
Anarchs and ground to make that work though you need a driver on the computer whether it's a PC a Windows
PC or a Mac or Linux or whatever.
You need a driver that can do that for you so that you can basically from some kind of API built into
the operating system C create a serial port sends serial data and then out of this magical device that's
connected to a USP port which has no serial which has a standard you know RS 232 serial you get this
T-Rex and you get this are X.
Right.
So.
So again let's let's just kind of draw this a little bit.
And this is important if you know you probably know this but if you don't it's not going to kill you
to review it.
All right.
So here's the problem.
We used to have our PC right and on the PC we used to have a port and this port was an iris 232 serial
port.
All right so this is a serial port and on this port it had a couple of lines that you needed in ground
and then it has other lines because a lot of times this was this was for modems right so it had modem
related things but Exarchs in-grown that's basically all you need.
So with these three wires you could basically take this over here take these three wires right and then
come over here and then you could build something that understood serial.
It could be another PC could.
Could it be another PC could be a microcontroller could be a computer.
You know some other small computer could be whatever could be this other device right here.
All right.
And that was really easy because it is a really easy protocol and standard It was just ones and zeros
and that was that.
Now the problem is once the USV came out there's no more serial ports.
Now there's a USP for it.
So now there's a USV for it.
All right we're all familiar with USV.
So now the problem is you can connect us reports from computer to computer as long as they have a USP
for it.
On the other end that's great.
That's fine or computer to device whatever.
That's great.
But what if you have some little device like a microcontroller a microcontroller based device that has
no USP But what it does have is a serial.
You are it's got t x It's got r x and of course it's got to ground.
How can I get these signals.
Well what you can do is you can take this USP and we can come down here.
Then what.
What's been developed is a device and this is called the U.S. be to serial cereal bridge and a few companies
make this.
And what this does is it takes the USV And then there is a serial device as part of the USP device suite
that the bottom bottom line output is you get t x x and then of course there's ground here.
So from the microcontrollers point of view it just seems eccentric.
So then you can basically connect this like this.
Right.
And then the cross-connect these things right like that.
So T-Rex goes to our X that that's just horrible.
Just not going you know what.
That's horrible too.
Let's do this here.
Here we go.
There's that.
Whoops.
We went to X to our X and let's use this color we want this to this.
They have to be cross connected.
OK.
And then grounds are tied together.
So here is this ground here.
And then these are tied together.
All right so the microcontroller can communicate with T XRX and cereal packets and send you know ASCII
characters whatever it wants.
And then this thing receives it and then it puts it into a USV packet and sends it back to the computer.
Now here's the problem on the computer we need some kind of driver that understands this.
So there's got to be a driver a USP serial driver plugged into the computer.
So here is this driver here.
And then here's your application here.
Your application and it talks to the driver and they want that driver to be so that it's transparent.
So from your point of view if you just create a COM port that driver will give you a U.S. B.Com port.
So it's completely transparent so from your programming point of view you don't have to change your
code.
So let's say you use an API call in Windows or Linux or Mac that said open up a COM port and you gave
it a number that API will still work completely untouched because it's the driver's problem to go install
itself and announce itself as a COM port so that the computer doesn't know the difference.
All right so when you have one of these USVI drivers one of these USV two serial bridges and now lots
of things habet you're probably familiar with this.
All right.
But if you were to go to your control panel over here and let me get it over here so we can see it.
Here you go here's my device manager.
All right.
And if you look inside your control panel here and we go down here to some it's in different places.
OK that's not what we want system of devices keyboards.
And of course it's not showing the way I want.
All right so maybe I don't have anything plugged right now that has an FDDI driver.
Let me see here.
As a matter of fact here we go.
So let me plug something in.
So right here this is got a teeny tiny FDDI.
And I get to show you this company so this is a use fee to serial bridge.
This is a tiny little product.
This is this one's made by Parallax.
I believe this is a USV of cereal.
All right so now if I plug this in what's going to happen is the computer is going to detect it.
So we got our V cable here.
You can see this and I want to plug it in.
And sometimes this works and sometimes it doesn't because it's got detected the drivers got to get installed
properly and a few things have to happen.
All right.
So you can see here down at the bottom.
Driver software it's installing so we can click on this.
Right.
And now the FDDI drivers are part of Windows Update and they're mostly part of everything now.
Mac and Linux all of these come with these FDDI drivers which at first you had to manually install but
now they just kind of come with the standard driver install so it should be able to recognize it.
So all right so there it goes.
And installing driver software was able to find it ready for use USV to serial converter.
Now it's still kind of working a little but what's happened is if you look over here in ports com Nagata
USV serial port comp's 6.
OK.
So now an hour ago.
So now it's got that and this little question mark should get off there and a second once it figures
this out.
Now what's cool is let's say that you have a terminal program that you'd like.
OK terminal program and let's see what what I have here in this particular installation.
So we've got those terminals right there.
Let me see do I have putty here.
And I've got putty.
All right so puttees a terminal program that I like.
So.
So here's putty which is just a standard terminal program.
Then we would we would go down a serial and then see here we could say connect to whatever line and
we would just say com 6 and then we say whatever speed we want this at.
All right.
And then what's going to happen is it's going to negotiate this and then we're going to be able to get
that and then flow control we want none.
So we could actually communicate like this or we could go through and we could say Microsoft's hyper
terminal hyper terminals a so-called I never use and I never use it anymore.
So lotsa different terminal programs and depending on your hair Izaak this is another one.
This may not even work because this is a free version of it.
Let's see cancell create new set see if that pops it up.
That's not doing what I want to do.
Anyway the whole point is now if you look at this it's just comp 6 doesn't know the difference so you
could use this and communicate however you want.
So that is what you need.
We need something like that to be able to talk to the PC because the Arduino software communicates to
the wino's over cereal.
So it needs the serial port.
And so he needs this whole bridging system here transparent.
And then the Arduino tool itself you know communicates through a computer.
OK.
So we need this USV to serial bridge all right so we know we need that right now.
So now we go in I'm going to show you this one in one second.
So there's a couple of companies silicon labs makes one FDDI so we could say USV and this is going to
be something hard to search for a serial bridge.
I don't know let's see or maybe we just put USV cereal might be a wiser less is more right USV cereal
when you're doing searching Let's see.
OK.
Interface Dirigo interface controllers are transceivers.
All right let's try interface controllers here.
OK.
And let's see.
All right so we look through here and see what all these things are doing.
So see these interfaces over here.
So these are showing different interfaces right.
So if we just put if we put serial interface for example.
All right I just want serial interface.
And we.
Well that only gave us one remaining.
And who's this coming from.
So this is micro-chip not sure what that what that does.
But anyway the point is you could search and there are other companies that make these things for the
primary company that does this is this FDDI.
OK.
So FDDI is the primary company that makes these these devices right now.
So let's go to FDDI.
So if you go to FDDI and not to be confused with the flour company you go to FDDI dot com are going
to get confused.
Go FDDI dot com unless you're sending flowers to your girlfriend or boyfriend.
Right.
Wrong Web site.
OK.
So this is the Web site right here.
And we go look at their products and they have got a bunch of products here.
So we'll look at these.
All right.
They've got this line of ice seas here and we go down here to the USV stuff and they've got this whole
series before they only had a couple.
Now they've just got many many too many.
A lot of confusing stuff they make graphics chips now and stuff all kinds of stuff.
But the common ship that you'll see for the FDDI USV the serial bridge chips are these guys down here
this F.T. 2:32 are.
And these chips down in this range right here these are USV to serve bridges so see.
Take a look at this.
2:32 are here.
All right now we go to the design here.
So this says F.T. 230 to our l can't remember what the L is.
If it's just the package I'm not sure we will have to check on that discontinued CS check on that real
quick.
No that's so we're good so I think the it's just the packaging.
All right.
So anyway we go here.
And so what is this thing.
So this is go here this data sheet.
All right look at this again we what we want to know what we're hooking up here right.
So I've used this chip many many many times for many many years.
And now newer versions of it.
So the F.T. 2:32 are is a speed of cereal.
You are interface with the following advanced features and a bunch of stuff right and it's got a driver
which they wrote royalty free so that from the PCs or the Linux or Mac it just looks like a serial port
which is exactly what you want.
Very advanced and it supports all these different things operating systems and versions.
Right.
And then it shows you kind of a block diagram here.
So over here we've got the USV connection power and things like that.
And over here we've got basically these are the outputs that give us our digital outputs right and these
can be programmed so that they're generically called Debussy's Seabass.
Right.
But come down here a little bit and kind of read through all the pins here and what they do and so forth
and figure this out.
And so just like anything to read the data sheet and I want you to read this data you're going to use
this chip so much and you're as you get more advanced you need to know how this thing works.
And like I said there's a couple other companies that make good ones.
So you can pick whichever one you want but what I want to show you is scroll down here scroll down scroll
down up here is a one little references.
And so this is showing us the power configuration so this is showing that chip is powered from the USP
right showing some bypass again showing something else here.
You know different reference designs.
Here's a little bit more of a reference design showing with power switching with the fat.
Right.
And then another little thing.
But what I want to show you is.
Yeah.
And then so here's a simple so this is say you want to just make an USPSA ARIST 2:32 converter.
This is kind of you know what you do.
You get your USV connector here which you've got to figure out and get one yourself.
Here's your power here is you know how this thing is all set up.
And then here is here's your signals here right now in this case what this is talking about is if you
want true RS 232 plus and minus voltages that would be this.
But if you don't here's the signals right here in our X and that's that.
And then all these signals this is request to send clear send data terminal ready dataset ready data
carrier detect ring detect.
This is if you're making a modem don't need all those who didn't x and are x.
OK.
Then when there's traffic on the thing in default mode C-bus 0 and C-bus one will flicker C-bus there
was X and see this one is Arek so when it's when there's a T-Rex or Ark's event these Ltd's these signals
will go on and off ones and zeros and then you connect up Ltds you could see traffic.
So this is this is basically what every one of these little devices has in it.
This kind of thing here with this chip This is just got one USP port on one serial port on it.
And then here's something else here if you want to do ours for 45.
They basically give you all these references lines.
OK.
So we have all these reference designs and it's telling you where things can connect and in all this
you have to read all this.
Here's a very ears exactly to a microcontroller.
Right.
So the XTi goes to the TXU the microcontroller the transmit out goes the receive the transmit out here
goes the receive here and then if you want this request to send it clear to send out those hardware
handshakes also.
Right.
Again if you don't know anything about Saral got to read about it right you get it you need to know
how this works.
OK.
All right.
And then again like I said go through this whole thing.
OK.
We're going to look at something different than this though.
So this is the F.T. 2:32 are OK if we go look at the reference design it uses NFT 2:32 r r r l.
Let's see what the whole story is there.
Right.
So let's go here and check it out.
And again it's a process.
This whole thing is a process not something we're going to do in an hour.
This is takes hours and hours hundreds of hours thousands of hours sometimes thousands of hours to develop
a product.
OK.
So here's the product right here.
And so this is four dollars and fifty cents for one of them.
It's the 2:32 Arel.
And I like I said I leave the L stands for the package version but it's the 2:32 R which we just looked
at the data sheet which we pop this up.
That's it.
OK.
So there our data sheet.
OK.
So now and we've got a bunch of snaps here we'll have to fix that.
Let's go back here.
OK so the browser got a little destabilized.
OK so we're back here on the F.T. 232 page here kind of searching.
And then what we saw was that the F.T. 2:32 and let's will F.T. 2:32 are L and go back here and look
here.
All right.
So it's a $4 and 50 cents.
Now if we look at the design.
All he requires to look at this up to an Arduino.
We just need to exit our X.
Here is our X and here cx.
Right.
So the T X out goes to the arcs of the processor and vice versa.
That's all we need.
All right and then one other thing.
There's DTA here data terminal ready now how the Arduino does resets is it.
It needs something to reset it.
So what what they did originally many many years ago they said well how can we talk with cereal and
do a reset kind of with a trick.
And one of those Trix's in the modem interface there's a bunch of modem lines data terminal ready request
the send ring indicator data set ready data carrier detect clear to send.
You can read what all those actually mean.
But one of them is data terminal ready and what you can do is if you in the API say take that signal
low or high.
You can control it from your serial API.
Usually they let you talk to the data terminal ready line.
OK.
Because of that the designers of the Arduino said Well what we can do is add the API to reset the Arduino.
You can pulse the Dietmar line pulse it and then we'll put a capacitor there maybe a transistor something
and then we'll connect that to the reset line.
So see there's a capacitor here.
Point one microflora.
It goes directly to the reset line right here.
OK.
Right to the reset then that's it.
And now you can also notice there's this pull up resistor pulling this high that's a little bit too
stiff for my taste.
So I'd make that like a 10K.
But anyway so that goes right to the reset line.
So all we need is X are X and data terminal ready we don't need all these other features.
Right.
So this chip is four dollars and fifty cents are you kidding me.
It's more than the processor costs right.
It's too expensive it's 450.
Right.
And then at 10000 it's 265.
Can we do better.
So if you look through the portfolio on FDDI of all their cereal chips you can find a better chip OK
the better chip is right here.
So it's the 2:31 ex-s are.
So let's take this and I just want to grab the text here.
Let's go look at it.
All right.
So 450 for one of the chip in the References line.
Can we do better.
Okay one is $2.
Look at that.
Right so right here.
And then at $508 60 anyway it's half as much.
Will it work.
Right now the cool thing is is all the FDDI chips from the driver's point of view that's running on
your PC.
It's no different from the driver's point of view.
It's you she open up a COM port and you don't know the difference so that's OK.
The question is at the electronics point down at the other end at the microcontroller point do we have
all the signals.
Are they the right signal levels and all that.
I don't know let's find out.
So let's go to the 2:31 X here.
Here's its data sheet.
Okay.
All right.
So here's what we're what we're talking about here.
So it's a cereal you are with full modem and falling advanced features.
It looks similar.
Okay.
All right.
And you'd have to read through this right.
And I did I read through this whole thing at one point and looked at and made sure it was all compatible.
All right.
And then so if you look at it here it's got our signals.
So it's got RTX R R R X and there's our data terminal ready.
So it's got what we need.
All right so the question is what's the difference.
I can't remember other than this newer.
All right.
And it's cheaper.
So I can't remember what the difference is in the other.
The other chip just may be older or maybe it has one feature this doesn't that no one uses so anyway.
Now on to excentric let's make sure that those are correct.
So so T-Rex is the output and our X is the input right.
So when we were looking at the design and we found that mistake labeled on the chip T-Rexes DX our x
is x is not the opposite so you got to be careful.
So somehow I flip those and we'll talk about that more and we get to in a second right.
So here is the chip and then we have to go look at its reference design.
Make sure we're doing everything the same.
So scroll scroll scroll until we can find a reference design.
OK.
So here is a reference design that says OK you know here's your USP port put your ferrite bead for noise
put some 27 ohm resistors in here for reflections and then you might want to pull these down some capacitors
also for noise on those lines.
Here's your bypass and then here is this whole situation right here.
Take reset which is active low pull it high.
So this VCO pull it high always.
And then this Visi CIO this is the IO voltage of the chip so you want it to be 3.3 volts or do you want
it to be Firebolt.
That's important right.
If it's 5 volts then these the outputs which are not shown in this block are going to be at that voltage.
You gotta be careful of that.
So right so that's showing us that right.
And then here is just another little variant here.
All right.
There's that same switch variant for mixing power supplies very similar to the other one very similar.
And then where's the one going to the processor.
There is one going directly to processor and I'm just looking to let it or face here.
You've got to look at that so you hook up the ladies correctly and these can be reprogrammed.
And we don't see it so I'm just looking for if it shows it here or if I just looked at all of them and
like I said I've used this many times so I guess maybe there wasn't just the single nice micro-controller
interface version.
OK.
Doesn't matter so I read the data sheet.
You need to read the data sheets 44 pages read it.
OK so now what I did was from that I built this so let's copy this whole thing.
All right so I'm going to do that we're going to say copy we're going to go to our final design here
and we're going to put it in here right over here someplace else say control the and hope that it fits
you up.
OK looks good.
OK.
OK so here we go Sinapis talk about this thing.
All right so now is talk about this thing.
All right so we've got our U.S. feed of cereal chip we've got our F.T. 2:31 again this is going to be
a surface mount chip obviously.
So I had to make sure that circuit maker had the footprint of this and it did.
So that was good so I didn't have to make it.
All right so now let's look at the design and let's see what's going on here.
So the first thing is we've got piece of CC and that's what's powering this thing.
It's going to be subsea $65.
All right.
So one way or another this is going to get powered either by the Vivus itself or by the regulator power
system.
So one way or another that's going to get powered.
OK.
This is By-Passed right here.
Now look at VCC IO.
That's also hooked up to the FCC which is hooked up to 5 volts which means my IO is going to be at 5
volts not 3.3 volts but 5 volts because the Atmel chip has a 5 volt ship so we have to make sure that
the IO voltages match each other otherwise when translators.
So that's important.
And by translators I don't mean language translators I mean 3.3 gets converted to 5:5 gets converted
to 3.3 so you don't damage anything.
OK.
Next we've got this three point three Volt out this is the chip has a built in regulator which can generate
this 3.3 volts out.
And I think it puts out maybe 50 million amperes.
We'd have to look at the data sheet.
Right.
We could say 3 3 3 3 3 3 3 3 3 3 3 3.
Yeah $50 $50 ampere so it can put out $50 Ampere's So it's not going to power a bus but that would power
you know a microcontroller and some other things that were low power.
OK.
Next we have the reset line its active low so we just try that because we don't ever care about resetting
the chip itself right in this case.
Next what else of our grounds.
All right.
Let's see anything else.
OK so here's USP data minus an USP data plus those go to the USP port plus and minus pins respectively.
Okay.
And here they go wrapping around here and hopefully I did this right.
So data mining state of mind state of mind state of mind state as mine is because of data mining data
Puskas data plus another really easy thing to flip around.
Right.
Very easy.
There are 27 OAM like in the spec now we need to use fi connector so the question is what do we want
to use on a micro mini or this or that you could put any connector you want.
So I like using mini connectors micros are just too small and flimsy.
So I picked this E-Tek.
Two reasons why there was a model and circuit maker and it's cheap and it's good.
So if we go here to Digi-Key take a look at it here it is here.
And oops six should be able to find it or Mouser will have it.
There it is right there.
So I did some searching.
Right.
It's got board guide solder retention it's a nice little connector and it's unshielded can handle an
amp so we go here you know at 500 it's only 34 cents.
Niceto connector nice little connector USV minivan.
Right.
OK.
So I could click on it and I can also see here is its 3-D model right.
And flip it around.
That's exactly what we want.
There are five little if I can remember there is each one of these interfaces is slightly different.
Yes so there's our little pins right there and again a really common place to make mistakes.
Figure out what pins is what on these USP connectors.
All right then we've got a fuse here.
Let's talk about this real quick so the fuse is simply if there is an overcurrent event a short something.
Right.
We don't want to blow anything out so this fuse will will open up.
So this is a a a fuse that a poly fuse that after it opens it closes so heat causes it to open up and
then it really solidifies.
So take it so it's you know resettable It's called a PTC and let's see if we can find it's part number.
Here we go.
So it's Bourne's which is a common company that I like to get fuses from and little fuse we've talked
about this before.
Here it is here.
Fuses tend to be a little bit big.
So here it is here.
So it can handle up to 15 volts so that's ok.
Current Max is 100 as Ford just explodes and it's no good.
The trip current is one amp so more than one amp flows to this thing for more than 150 milliseconds
it's going to pop right and open up in the reclose that probably means there is a short otherwise you
can maintain 500 amps.
No problem.
Of course you can change that so this is got a certain size.
If you scroll over here the size is an 18 12.
So that's pretty big surface mount device 18:12 what it looks like that's what these fuses look like
very nice and very safe.
OK.
All right.
So we got our fuse there.
We've got a Shaki diode and all the Schottky diode is just making sure that current only flows in one
direction to get our bypass capacitors right.
So everything is as it should be.
And then the only other thing is you've got TXI going out.
And so this X here this is an output goes to our X and this our x x from the processor connects here.
Right.
So each one is opposite but we have to make sure we get these labeled right now.
So here's our X going to our X and here's x and x.
Ok so I'm happy.
OK.
So there is our entire US a serial bridge.
We don't know anything about us.
We have no idea how it works.
Right we didn't write the driver for it won't to do anything.
But if you look this circuit up at the end of the day you're going to get t XRX from the PC and then
on the PC side some other smart guy took care of writing the driver for you a virtual COM driver it's
called right.
So that when you write an application in C C++ C Sharp javascript Python you name it and you open a
COM port and you grab a COM port the COM port can be a physical COM port or can be a virtual COM port
via the USP and you won't know the difference.
You won't have to change your coding which is awesome.
Ok let's come back here.
All right.
And why do we need this again.
Because after we've programmed the bootloader onto the Arduino through the programming port and put
the boot loader on there that makes it an Arduino then we don't use this anymore when this thing powers
up.
It says I want traffic through here.
So on the PC we run the Arduino software and the Arduino software sends the traffic through the ARIST
2:32 through the comm port which ends up here.
But to start the whole process off it has to reset the processor.
How does it do that.
It does that through the DTI underline the data terminal ready.
It pulses it and there's a little tiny capacitor because it's an AC pulse right pulse.
It goes to the capacitor hits the reset line reset and which just means reset active low put it and
mean it's active could put a bar over things whatever and then that will reset the process from the
processor or start the bootloader and that'll be that.
OK.
So there is the entire U.S. V.S. right.
Isn't that cool.
So we got our USP we got TXU got Arc's we got our data terminal ready for reset.
One last thing the traffic here so C-bus 0 is TMX and C-bus 1 is our X. I hope.
So the way it is in default I believe that's correct see VASILIOS T-Rex and C-bus one is our.
Worse comes to worse the label would be wrong on the silk screen or you could go.
You can actually reprogram these chips over USP with a tool from FDDI and we could actually change that
but I think that's correct.
I'm pretty sure it's correct I looked at the data sheet but again I'm not perfect so I could could be
wrong but it's pretty consistent through the different versions.
And if we look over here Ciba zero is going to the are X so C-bus Ciro's are X and then C-bus one is
x.
We go over here see Suro is TMX C-bus 0 is our X and C-bus one is x.
So these are backward relative to that one again.
Again it's so easy to make mistakes and again I'm using a different chip here.
So you know this X and R X also can be flipped around right.
So that's another thing you can flip the TXI and the arcs around which is nice if you do put it in backwards.
You can program it and flip it around.
So maybe I read something and again I did this a while ago so maybe I read something that says something
different.
Let's take a quick look here.
Take a quick look here.
And remember this is all about
all about.
This is all about you know schematic design and PCB layout and then the other engineering parts so this
is a much bigger process right.
You have to read these things you got to go through.
You got to take notes get to engineering notes.
You know I've got countless countless books here full of notes as I do this stuff and you need to do
that too and keep your engineering notes right.
But anyway if we look at the pins here the C-bus 0 configurable C-bus pin.
Like I said it can be what you want but the default configuration is transmit an able and C-bus one
the default configuration is.
So let's see here.
So we got to be careful.
Got to be careful here.
So.
So this is our next lead and this is Teac sled so C-bus one and two.
All right so we got to be careful here.
So so we may have made another little mistake.
So and again I'm copying this so many different times.
All right.
So we need to make sure we're using the right package for.
So what package are we using.
Let's make sure this.
Let's let's go here.
Backdoor design.
All right.
So we're using this ex as our package let's double click in to here and let's see here.
So this I believe this is this.
They call this this SS 0.20 SS opii twenty package is is the path package.
SS 0.20 OK.
So it's the SS 0.20 package.
And again let's go through this this is really good.
So here's the SS 0.20 package right now.
Here is the QF n package.
All right.
So we're using the SS 0.20 package or I say let's be careful.
SS O.P. twenty package this is the package we're using.
All right.
And on this particular package we've got C-bus zero and see once each of us to see was three did we
do something wrong here let's find out.
So this is the SS O.P. penult disruptions right.
So let's scroll down here now it says that C-bus 0 is TXI the enable right configured device to add
a default configuration right.
In table 3 7 we're going to take a look at that.
But C-bus one is our X and C-bus two is X C-bus one is our X of us two is DXO.
So that concerns me.
So if we look here if we look here we've got this to zero in one now we could really reprogram this
but I don't like that.
So C-bus one is our.
So C-bus one is our X..
So that's correct.
SIEV-X bus one is our X. But C-bus 2 is T-Rex here cx.
So this is actually wrong.
So let's let's go here and we're going to go down here and connect this to like that and close that
and then so now we don't want to delete the whole wire remember all we can do we can right click on
this and say break wire and we can go here and we can break the little wire there.
Right.
Then we can select it and delete it.
Right and then we can shrink this down.
Hopefully it will cooperate with us.
OK so.
So that was that's potentially wrong.
So we got t x here and now we got our X..
All right.
And so now that would be right because the way this default is a C VASILIOS is T-Max enable.
All right so we got to kind of look at that also.
So look at that a little bit.
And we want to look at Table 3 7 also.
All right.
So let's see let's go to the table 3.7 3.7 3.7 3.7.
And this is this is the process you got to sit here and go through this stuff and you know figure it
out.
Here it is right here.
And let's see configuration control this does is it really helping us any.
All right so.
So anyway it looks like we want those pins the the way that we had them that we just made a change for
TXI generics.
And if we go back down here and go to the SS soapie version C-bus and that's why you get to read this
because there's a little little little tidbits here and here so see this T-Rex T-Rex lead can be on
any of these pins Arc's lead can be in any of these pins.
All right.
And then enable transfer data for our 45 mode.
Right so we don't need to worry about that now.
So.
So we had it on 0 and 1.
So we had it on zero on one if we look at his references.
So he's got his on zero and 1 let's see if the default for the 32 Arel is zero on one and I bet you
it is.
And I may have just copied that.
So let's go here.
And this whole thing we're talking about very very lots of tiny little minutia details that we got to
be careful of.
All right so let's go down.
We're going to find the opin out here.
Right.
So
so here we go.
Yeah.
So this C-bus zero default on this version of the chip is a little bit different.
So C-bus 0 is TXI of us one is aurochs see that and then C-bus 2 is is TXI enable so.
So anyway I tend to believe that the data sheets are correct but it's possible they could be wrong.
Seen it before.
I can't remember if if it's if it's incorrect in a bug in the data sheet but we're going assume that
it's correct and we're going to assume that this is right.
So that on C-bus 1 and 2 is our x and t x respectively.
We're going to design it like that.
The good news is if we're wrong we can go into the chip over USP and actually reprogram this stuff and
that's why this is nice because anything here that's on the C-bus you can reprogram right.
I even believe you can flip to and are X and you could flip the polarity of them as well.
OK so they the guys who made this know that this is a problem and they know that this happens OK.
So we're going to leave this like this.
All right and then we're going to have to go back and we're going to fix that.
I'll go do it.
Inside of here in the work copy.
So go back to here to the work coffee real quick.
All right we're going to go to work copy and let's go and fix this right here to reflect what we just
read.
And this is this is good because what's happening here is we're we're going through this and we're figuring
things out.
And you know you got to do this to make sure that you've got everything right and that's just all there
is to it.
And so by me going over this design with you we're finding little errors and that's great because I
want to find errors because it's pretty suspect that I'm perfect.
Right.
I'm not.
And so if I don't find any errors that means I probably made some money and find him so we're finding
some errors which is good.
OK so this is now the same here.
OK.
So now we're going to go back to our final OK.
All right so let's see we got our USP we've got our processor we got our power got a leading indicator
got a reset switch we got our programming port.
What else do we need.
All right.
What else do we need here to copy over.
All right so we've got our audio amplifier and then we've got our whole input interface here and we
got our de-bunk.
OK.
So why don't we let's stop the video here and then we're going to come back and let's deal with these
three elements.
OK.
And of course make sure if you're you know you probably are not following along or just watching because
it be too hard to follow along right now.
But let's make sure we save everything and commit everything.
Make sure everything is all synchronized to the cloud.
You know we keep doing that.
I hit Control s constantly at least.
OK.
So anyway so I'll see you in the next video and we'll go out those other three elements right.
By.