FTDI USB - As good as they claim?

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Having had a search around the forums here, I gather that the general opinion of the FTDI USB chips is that they are pretty good.

If the salesman is to be believed, using simple RS232 at the microcontroller end and their driver at the PC end, bidirectional comms miraculously occurs and I never need to worry about the USB transport mechanism.

For an application we have, we need to keep about 4Kbytes of data in synch between an embedded micro and a PC more often than roughly once per second.

Notwithstanding the fact that we have to implement a protocol to achieve the synchronisation (my problem, I realise) are these chips really up to the job?

How about if somebody else has a device using the same technology? Is their driver clever enough to be able to address MY device rather than the other one?

Thanks for advice in advance.

Andy

If we are not supposed to eat animals, why are they made out of meat?

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They truly are as good as they claim. I use them daily at 3,000,000 bps here!

If you are using the FT232 chip, you better hook up 2 more lines for RTS/CTS or you will have problems with overflows at high baud rates.

I prefer the FT245 but it requires 4+8 lines.

Regards

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I recently bought a Keyspan USB to serial adapter to use on my laptop and it uses one of the FTDI chips. I figured out which one it was by the specs but couldn't even begin to tell you which one it is from memory now.

Anyway, it works like a charm. The laptop doesn't seem to have a clue it is communicating with RS-232 devices. It thinks it's a USB or maybe is fooled into thinking it really does have a serial port.

What I do know is all I did was plug it in and it worked.

Please note - this post may not present all information available on a subject.

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Hi all

I also use the FT245BM and am very fond of it.
I have designed a small board wit it an an ATMEGA128 on it:
http.//www.megausb.de (german)

It is fast, and easy to use. We work both with Windows and Linux.
And YES, you have the ability to store your own PID and VID into a serial EEPROM connected to the FT245. With this your USB device is unique. Also you can configure:
your * serialnumber * vendor name * device name * power requirement of your application * timing * other functions * and mode of transmission. For example you can use isochronous mode for transferring data with a certain bandwidth.

There are VCP and D2xx Driver. While VCP is the easy way, the D2xx is the more flexible. I recommend starting with VCP and if necessary then step over to D2xx.

Have a lot of fun!

Klaus
********************************
Look at: www.megausb.de (German)
********************************

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Thanks, folks.

I suppose that "wow" is the appropriate response.

Cheers
A

If we are not supposed to eat animals, why are they made out of meat?

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Andy - have you heard of the CP2101 made by Silicon Labs? Here in the states it is much cheaper and easier to get than the FTDI chips. Seems to be well regarded but less well known compared to the FTDI chips. Best regards..

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ezcomp wrote:
Andy - have you heard of the CP2101 made by Silicon Labs? Here in the states it is much cheaper and easier to get than the FTDI chips. Seems to be well regarded but less well known compared to the FTDI chips. Best regards..

It may be a fine chip, ez, but "much cheaper" and "easier to get"?

--I did not find any listing of distributors on the Silabs Web site, so I actually found it >>harder<< to get info. :)

--On-line buying kicked into Mouser
Qty. 1 price: $5.70
Qty. 100 price: $4.02

--FTDI from Saelig:
Qty. 1 price: $5.80
Qty. 100 price: $4.30

--We have had good and fast service from Saelig.

Is there a disti that sells the chip "much cheaper"?

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Thanks for the alternative gentlemen.

I will point our hardware guy at the site.

That is assuming he can still access the Net following the hurricane that is about to pass right over him on Monday evening.

I can't help feeling he could have picked a better time to visit his sister in Florida. :D

Cheers
A

If we are not supposed to eat animals, why are they made out of meat?

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MegaUSBFreak wrote:

And YES, you have the ability to store your own PID and VID into a serial EEPROM connected to the FT245. With this your USB device is unique.

Don't you wish they would just stick some EEPROM in the damn thing anyway, I'd be more than happy to pay the extra $$ if it ment losing 1 IC and a few resistors that are needed if you run the EEPROM.

Apart from that they are a very good choice.

Cheers.

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vimfuego2 wrote:
MegaUSBFreak wrote:

And YES, you have the ability to store your own PID and VID into a serial EEPROM connected to the FT245. With this your USB device is unique.

Don't you wish they would just stick some EEPROM in the damn thing anyway, I'd be more than happy to pay the extra $$ if it ment losing 1 IC and a few resistors that are needed if you run the EEPROM.

Apart from that they are a very good choice.

Cheers.

Just in case you are not aware, one of the things that make the CP2101 atttractive is that there is no need for a separate EEPROM and crystal. It is truly a one chip solution (plus a single bypass cap).

Scott

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Another note - the CP2101 is IN STOCK at Digikey :D FTDI Chips didn't seem to share that ...

-Colin

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Thanks Colin,

I know what I will be getting...

Caleb

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BTW - for anyone who hasn't found this site yet, www.findchips.com is a great resource when new chips are announced. It will search a bunch of distributors so you can get an idea of how available it is.

-Colin

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sarmitage wrote:
Just in case you are not aware, one of the things that make the CP2101 atttractive is that there is no need for a separate EEPROM and crystal. It is truly a one chip solution (plus a single bypass cap).
Scott

One question though: anybody can tell me how on the Earth to solder the 28MLP CP2101? (I, Hobbyist).

Bogdan

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lethal wrote:
sarmitage wrote:
Just in case you are not aware, one of the things that make the CP2101 atttractive is that there is no need for a separate EEPROM and crystal. It is truly a one chip solution (plus a single bypass cap).
Scott

One question though: anybody can tell me how on the Earth to solder the 28MLP CP2101? (I, Hobbyist).

Infrared oven will work quite nicely, as will a 'hot air pencil' type soldering iron.

I have experimented with the CP2101 which we chose simply because of its size! We are starting to use the MLFP packages for AVR parts and whilst we have yet to produce a finished product we have found the MLFP quite usable in prototypes.

One robotics supplier, ( http://www.pololu.com/products/pololu/0391/ ) is usaing the CP2101 on a triny little board with a mini-B USB connector.

...John

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I have done small prototype builds using Atmel and SiLabs MLF packages using a modified toaster oven (Google for "toaster oven soldering"). Out of about 10 chips that I have soldered this way, I have had 100% success with no rework required on any of them. Typically on a fine pitch QFP I need to touch up about 10% of the pins.

Scott

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hi
what about philips PDIUSBD12 ics?

Atmel used them in jtag mk II!

Is it better that FTDI in performance ? and in price?

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yaaavar wrote:
hi
what about philips PDIUSBD12 ics?

Atmel used them in jtag mk II!

Is it better that FTDI in performance ? and in price?


I beleive you need to write a lot of software to interface this chip, it's only the phsical interface. It's much more complicated to interface than a simple RS232 interface as on the FTDI232, CP2101 and Prolific PL-2303 / PL-2313.

Link to PL-2303 and 2313: http://www.prolific.com.tw/eng/P...

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CP2101 can be bought cheaper at Sparkfun in small quantities than at Mouser and Digikey:
http://www.sparkfun.com/shop/ind...

CP2101 prices:

Dealer    Price

Spark Fun $5.25
Mouser    $5.70
Digikey   $5.70
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Got experience with the CP2101? They look like a really nice chip (only problem is extra-tiny size) on paper, haven't heard yet though of people's experience so would be very interested in it!

Regards,

-Colin

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I have no experience with the CP2101, but lots with most of the FTDI chips. But after a quick look at the CP2101 I might consider switching. The only thing I dont like is thier method of driver distribution. FTDI does this part for you, at least for the generic drivers. To get the CP2101 drivers you need to get the DEVKIT. Still thats not too bad, only $50. But you still have the pain of distributing the drivers which can cost bandwidth and/or media. What happens when they have a driver update, do I have to buy another DEVKIT?

Vern

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Hi,

Once you buy the dev-kit you get free driver updates:

Quote:
For driver updates, contact MCU Tools Support to receive instructions on downloading the latest VCP drivers. To receive this information a valid CP2101EK serial number must be included with the request.

-Colin

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snafles wrote:
I have no experience with the CP2101, but lots with most of the FTDI chips. But after a quick look at the CP2101 I might consider switching. The only thing I dont like is thier method of driver distribution. FTDI does this part for you, at least for the generic drivers. To get the CP2101 drivers you need to get the DEVKIT. Still thats not too bad, only $50. But you still have the pain of distributing the drivers which can cost bandwidth and/or media. What happens when they have a driver update, do I have to buy another DEVKIT?

Vern

ftp://cp2101:cp2101xfer@ftp.sila...

The Readme.txt on the ftp site describes how to uninstall the old drivers and install the new ones.
You can also download the latest drivers using Windows Update.

So, just use Windows Update, it doesn't get any easier than that!

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Hi all,

I've used the CP2101 with a Mega32L and it was extreamly easy to use. It was actually quite surprising how easy it was.

The only "issue" I had was that I had to buy the development kit in order to get the USB drivers. This was some time ago so I do not know if they still require that. It might be something to look into before you use this chip.

I would have to say soldering the chip to my PCB was actually the hardest part though I was still able to HAND solder it to my PCB.

On a side note...I paid about $60. CND for the kit....(make that $63.98 digikey.ca :o ) and I sampled the chips from Insight.

I'll post a picture of my PCB with the CP2101 attached later when I get home from work if you like..

ocnek.

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ocnek wrote:
The only "issue" I had was that I had to buy the development kit in order to get the USB drivers.

I can see you didn't read the post above I just made.
There's a link to download the drivers from their ftp.
But it's even easier just to use Windows Update and download the driver from Microsoft.

You can even download the driver from Microsoft manually without having the chip yet.
I did that some time ago.

There's no reason to waste your money on this kit I think.
Just buy the chip and connect it and let Windows Update handle the rest. Or download the driver manually from Microsoft or the Silabs ftp.

Here the link once more to download the drivers:
ftp://cp2101:cp2101xfer@ftp.sila...

You can also download it manually from Windows Update here:
http://v4.windowsupdate.microsof...
1) Click "Find hardware driver updates"
2) Go to the bottom of the list and click "Other Hardware"
3) In "Manufacturer name:", choose "Silicon Laboratories Inc."
4) Choose your Windows operating system
5) Choose your Windows language
6) Click "Search"
7) Find "Silicon Laboratories usb software update released on March 11 2004." and click "Add"
8) Click "Go to Download Basket"
9) Click "Browse" and specify the download location of your choice
10) Click "Download now"

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AndersAnd wrote:

There's a link to download the drivers from their ftp.

There's no reason to waste your money on this kit I think.
Just buy the chip and connect it and let Windows Update handle the rest. Or download the driver manually from Microsoft or the Silabs ftp.

Here the link once more to download the drivers:
ftp://cp2101:cp2101xfer@ftp.sila...

I'm also interested on other people's experience with this chip and especially the driver. I've had problems with their "latest" driver and Windows XP, even though the claim it's for XP.

Thanks
Eric

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EW wrote:
I'm also interested on other people's experience with this chip and especially the driver. I've had problems with their "latest" driver and Windows XP, even though the claim it's for XP.

Have you tried to to download it with Windows Update instead of from Silabs ftp?
Maybe this version is different.

What kind of problems have you had?

Now you can also download FTDI drives with Windows Update, you coudn't do this half a year ago.
Just choose "Future Technology Devices International Ltd." instead of "Silicon Laboraties Inc."

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AndersAnd wrote:
EW wrote:
I'm also interested on other people's experience with this chip and especially the driver. I've had problems with their "latest" driver and Windows XP, even though the claim it's for XP.

Have you tried to to download it with Windows Update instead of from Silabs ftp?

No.

AndersAnd wrote:

Maybe this version is different.

I can't fathom why it would be different.

AndersAnd wrote:

What kind of problems have you had?

The driver will work fine for a while and then suddenly upon connecting the USB device, the PC will no longer recognize it. After that, it will continue to not recognize the USB device until the driver is reinstalled. :( It's sporadic and there no one way that I can get it to consistently fail, but it's happening often enough.

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What does Silabs support say about your problem?

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EW wrote:
The driver will work fine for a while and then suddenly upon connecting the USB device, the PC will no longer recognize it. After that, it will continue to not recognize the USB device until the driver is reinstalled. :( It's sporadic and there no one way that I can get it to consistently fail, but it's happening often enough.

I had a similar problem when I first started using the FTDI chips. I was doing a lot of testing, connecting and reconnecting the USB cable (the device was USB powered, so the easiest way to reset was disconnecting). After a couple times the PC would not recognize the FTDI chip anymore. I would do the same thing you discribed to get it to work again, but after some frustration with that, I found it easier to just disable, then reenable the COM port. That did the trick with FTDI chips, maybe it would also work for the CP2101 instead of the reinstall.

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I've got an FTDI kit that I haven't started playing with yet, BUT, I do remember reading somewhere on their web site about this problem. It's because the PC "thinks" that every re-connection is a new device. I believe there is some "fix" for OEM's who want to test stuff before it goes out of the door without having to constantly reset the PC.

Four legs good, two legs bad, three legs stable.

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Here is an interesting module for prototyping or us that can't solder mlf

http://www.qortek.com/ProductDet...

Dunno about pricing or availability.

/Bingo

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@John Brown

The "fix" can be found here, John, third item down the page.

http://www.ftdichip.com/FTApp.htm

/A

If we are not supposed to eat animals, why are they made out of meat?

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AndersAnd wrote:
ocnek wrote:
The only "issue" I had was that I had to buy the development kit in order to get the USB drivers.

I can see you didn't read the post above I just made.

I was just posting my experience with the part which was where this thread was going was it not?? Is that ok with you? Maybe I should have asked for your approval before I posted??!!…... :roll:

I first used this part when Cygnal was a separate company from SiLabs and the CP2101 was relatively new so buying the DEV kit was the only way to get the driver.

This might not be the case now as you pointed out, but at the time of MY development it was.

Quote from my distributor:
“Are you going to get a kit? I checked and you can't get the drivers without the kit. The kit is $49US.”

I beg for your forgiveness,

Ocnek.

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AndersAnd wrote:
What does Silabs support say about your problem?

Um, nothing. We haven't contacted them about it yet. :oops:

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snafles wrote:
EW wrote:
The driver will work fine for a while and then suddenly upon connecting the USB device, the PC will no longer recognize it. After that, it will continue to not recognize the USB device until the driver is reinstalled. :( It's sporadic and there no one way that I can get it to consistently fail, but it's happening often enough.

I had a similar problem when I first started using the FTDI chips. I was doing a lot of testing, connecting and reconnecting the USB cable (the device was USB powered, so the easiest way to reset was disconnecting). After a couple times the PC would not recognize the FTDI chip anymore. I would do the same thing you discribed to get it to work again, but after some frustration with that, I found it easier to just disable, then reenable the COM port. That did the trick with FTDI chips, maybe it would also work for the CP2101 instead of the reinstall.

Sure, it might. But it's not a good long term solution for customers using the product out in the field.

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ocnek wrote:
AndersAnd wrote:
ocnek wrote:
The only "issue" I had was that I had to buy the development kit in order to get the USB drivers.

I can see you didn't read the post above I just made.

I was just posting my experience with the part which was where this thread was going was it not?? Is that ok with you? Maybe I should have asked for your approval before I posted??!!…... :roll:

I first used this part when Cygnal was a separate company from SiLabs and the CP2101 was relatively new so buying the DEV kit was the only way to get the driver.

This might not be the case now as you pointed out, but at the time of MY development it was.

Quote from my distributor:
“Are you going to get a kit? I checked and you can't get the drivers without the kit. The kit is $49US.”

I beg for your forgiveness,

Ocnek.


You canpost whatever you like, but from your previous post it loked like you had not read my post:
ocnek wrote:
The only "issue" I had was that I had to buy the development kit in order to get the USB drivers. This was some time ago so I do not know if they still require that. It might be something to look into before you use this chip.

You wrote that you did not know if you still needed the dev. kit to get the drivers.
But if you had read my post you would know that you don't have to buy the dev. kit, because I told about two places to get the drivers without ordering the kit.
So if you really had read my post I find it strange that you write that you don't know if they still require you to buy the kit to get the drivers.
So I reallydid thought that you must had missed my post.
So I'm sorry if my English isn't good enough, so you didn't understood my first post.

But I don't mind if you read my post or not, lets just let it rest.
It doesn't really matter if you read my post or not, I guess you have read it now.

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AndyG wrote:
@John Brown

The "fix" can be found here, John, third item down the page.

http://www.ftdichip.com/FTApp.htm

/A


Well, thanks for that, as I said I'm not actually using it yet, I was just trying to point these other people in the right direction. Judging by some of the recent posts, I was wasting my time, as usual.

John

Four legs good, two legs bad, three legs stable.

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@AndersAnd

I think you are being a bit harsh here.

You might have given an alternate way to obtain the drivers but according to this text "snipped" from the Silabs Eval kit page , you could easily get the impression that the way you described were not the desired way.

At least in Silabs way of thinking ....

Quote:

Note: Virtual COM Port (VCP) device drivers are required for CP2101 device operation and are only distributed as part of the CP2101EK evaluation kit. Therefore, a CP2101EK kit must be purchased to use CP2101 devices. For driver updates, contact MCU Tools Support to receive instructions on downloading the latest VCP drivers. To receive this information a valid CP2101EK serial number must be included with the request.

/Bingo

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I'm sorry but I was not trying to offend anyone.
But from his post, I was really sure that he had not read my post, otherwise I don't understand why he wrote what he did.
Maybe I misunderstod something, but I can only understand his post as he don't know where to get the driver without ordering the kit.
I wasn't tying to offend anyone, but just wanted to point out that I had already given the answer to his question in the previous post.
I have never bought the kit, but just mailed Silabs to get the drivers.

I don't want to discuss who read what or not anymore, I don't really care I just wanted to give the answer to the question.
I think everyone know where to get the drivers by now.
.
The other discussion leads nowhere, I only want to discuss the topic from now on.
Write what you want about my posts, but I don't want to discuss it anmore. I was not trying to offend anyone. If you want to offend me go ahead, but I don't want to answer this anymore.
Let's keep to the topic insead, at least I will from now on.
Sorry I went a bit off topic.

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After reading about the fix at FTDI, it looks to me that the device will not get a new COM port every time, if it is given a unique serial number.

Do you have this problem with the FTDI or CP2101 chips if you have stored a serial number in the EEPROM?
If it recognises the serial number, I think it will be assigned the same COM port nuber again, so you wont run out of COM ports after 256 inserts.

To all with this problem:
Have you stored a serial number in the EERPOM?
I think this would solve the problem. Of course this would only work if you are not testing more than 256 different CP2101 or FTDI. But for noraml use with only a few different devices conected to the same PC I think it would work to assign induvidual serial number to the EERPOMs.

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AndersAnd wrote:
To all with this problem:
Have you stored a serial number in the EERPOM?
I think this would solve the problem. Of course this would only work if you are not testing more than 256 different CP2101 or FTDI. But for noraml use with only a few different devices conected to the same PC I think it would work to assign induvidual serial number to the EERPOMs.

I think there are three problems being discussed here:

1) The CP2101 drivers hang up on EW when he connects and reconnects the same device. I cant really speak to this problem since I have never touched the chips or drivers.

2) The FTDI drivers hang up when I connect and reconnect the same device. In my case it was the Demo board for the FT232 (DLP-USB232M). I kept the default settings for device and serial # and all that. My problem was it would just stop recognizing the device at a random number of disconnects connects. It wasnt really a problem because the driver never failed in the first few times, it really was a higher amount. It only ever happened during my testing, never had tester or customer complain with everyday use.

3) The FTDI "fix" is when you connect and reconnect many different devices. The example they give is a manufacturer testing thier product coming off the line. This shouldnt really apply to the hobbiest who is working on the same device.

Hope this clears up the confusion, or maybe made it worse.

Vern

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Actually I think it all the same problem and not three different.

When the have not been programmed with a serial in theEEPROM, the driver will think it's a new device every time the same IC is connected because it can't find it's serial number.

Have anyone with this problem programmed an serial number in the EEPROM, so the PC will realise it's the same device every time it's inserted?

I think the PC will regard a single IC without a serial as differnt devices every time it's inserted. If it has a serial I think the problems will disappear.

Can someone confirm this or prove otherwise? Have anyone with this problem programmed a serial number in the IC?
You said you used the default setting, but is there already programmed a serial number in the default setting, don't you have to do this yourself first?
HAve you tried to give it your own USB VID, PID , Serial Number and Product and see if the problem still exists.
I can't find any info in the DLP-USB232M datasheet that says this information has already been programmed from the factory.

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I cant speak to the CP2101, but the FTDI 232BM chip will not send a serial number if an eeprom is not attached. I cant remember what effects that has on the PC. As for the DLP-USB232M devkit for the FTDI 232BM chip, it has a default serial number programmed into it, I just checked mine. So its should not have made a difference. The same device was being plugged in over and over. This was a couple years back, but I am pretty sure I wasnt even close to the 256 limit suggested. My problem, guessing here, was happening between 30 and 50 times.

Vern

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Ok, I see, then I don't know what the problem is

snafles wrote:
I cant speak to the CP2101, but the FTDI 232BM chip will not send a serial number if an eeprom is not attached.

The Silabs CP2101 has integrated EEPROM and resonator. That's the biggest advantage vs. the FTDI 232BM.

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All that being said, I think for the next project using serial comms, I will be trying the CP2101. The reduced component count should make it worth its weight in gold. I will be ordering a dev board this week.

Vern

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I just connected up my FTDI 232 module today, talking to a hard disc video capture unit. Very trivial application. Works fine, but there is a BIG delay (several seconds) when I connect the USB cable( WIN98SE).
I now want to try the Silabs chip, like everybody else, I'm attracted by the in-built EEPROM and resonator.
Has anyone noticed a similar delay with the CP2101?
Has anyone managed to purchase a CP2101-EK in the UK?

Four legs good, two legs bad, three legs stable.

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John_A_Brown wrote:
Works fine, but there is a BIG delay (several seconds) when I connect the USB cable( WIN98SE).

With WIN98SE, I'd consider >>any<< successful USB communication with any of the chip brands a moral victory.

Before worrying about the delay part I'd try it on one of the newer operating systems with full USB support. I'm confused though about "BIG" and "several seconds". I haven't paid that close attention but we've got digital cameras, PDAs, FTDI devices, commercial USB-to-serial adapters, etc. in the office. We use them and test them on different Windows types including 98SE, XP/Home, XP/Pro, 2000. [Apps are checked on W95 & NT4 also.] I can't recall any device that "snaps to life" instantly. "Several seconds" does not seem "BIG". I'll have to pay more attention the next time we make the rounds. How do you measure the time?

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Unfortunately I can't tell every customer that they need to "upgrade" to WIN XP or NT.
I wouldn't care so much about the delay if there was a message of some sort, or even if the cursor stayed in "egg timer" mode, but what actually happens is that the computer stops responding to mouse/keyboard events.
How do I measure time? "One Mississippi, two Mississippi" etc. Is there another way?
But I take your point, and I will try it on XP.

Four legs good, two legs bad, three legs stable.

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John_A_Brown wrote:
Unfortunately I can't tell every customer that they need to "upgrade" to WIN XP or NT.

Actually, you could--assuming all USB devices operate the same way on 98SE. Then it is just the nature of the beast: upgrade, live with it, or you can develop the proper patch for '98. :twisted:

"How do you measure?" I mean from when (the time you plug the device in?) till when (the time the forst message is successfully transmitted/received?). What about other commercial USB devices--cameras, PDAs etc. [Here is my wager of a cold one: You and yours have probably not done much of that, because: A. the devices aren't supported on 98SE; and/or B. they work so crappy no-one wants to use them under 98SE, so they don't.]

But I'll take note of it when we're making the rounds with our USB devices and see if I get the same symptoms. We just rolled out a small lot of USB-to-RS485 converters using FT232BM & DS485, and plugged each into a 98SE system as well as the other Windows flavours that I listed, and didn't notice any particular anomalies. That is always like comparing apples and oranges, of course, since different drivers may be needed (and some XP machines need no driver load), etc.

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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I'm kind of fuzzy on this. If I connect an AVR project to a PC using this Silabs chip, then what can I do with it? Can I flash the AVR? Does it just act like a serial link, like I could talk to it using Windows Terminal? Would I have to write a PC program to communicate with it?

j.

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