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What is the best USB-to-RS232 adapter out there?

Started by Chris_99 May 12, 2006
Gang:

Now that all the cuel new laptops have no serial ports and no PCMCIA
card slot, and I am stuck  haplessly with USB, does anyone have a good
experience with any USB (or fire-wire) serial devices?

I have many legacy apps that want to talk to a UART real bad and the
quality of the driver would be the issue here.

I would really appreciate a couple of names of devices I could purchase
and try with all of these old utilities...

Thanks!

Chris

"Chris_99" <cgruff@gmail.com> wrote in message
news:1147445661.638683.82720@d71g2000cwd.googlegroups.com...
> Gang: > > Now that all the cuel new laptops have no serial ports and no PCMCIA > card slot, and I am stuck haplessly with USB, does anyone have a good > experience with any USB (or fire-wire) serial devices? >
The ones with an FTDI chip inside. Meindert
Meindert Sprang wrote:
> "Chris_99" <cgruff@gmail.com> wrote in message > news:1147445661.638683.82720@d71g2000cwd.googlegroups.com... > > Gang: > > > > Now that all the cuel new laptops have no serial ports and no PCMCIA > > card slot, and I am stuck haplessly with USB, does anyone have a good > > experience with any USB (or fire-wire) serial devices? > > > > The ones with an FTDI chip inside. > > Meindert
Meindert: Thanks for the tip. Found FTDI stuff at Parallax,Inc. in the States thanks! Chris
On 2006-05-12, Chris_99 <cgruff@gmail.com> wrote:

> Now that all the cuel new laptops have no serial ports and no > PCMCIA card slot, and I am stuck haplessly with USB, does > anyone have a good experience with any USB (or fire-wire) > serial devices?
I've tried 3-4 different USB ones and they all worked fine. I think they all use either the PL2303 or the FTDI chipset. Both chipsets are recognized by Linux out-of-the-box and are purely plug and play. If you're using Windows, you'll have to go download drivers from somewhere and reboot 9 times.
> I have many legacy apps that want to talk to a UART real bad > and the quality of the driver would be the issue here.
No problem if you're running Linux.
> I would really appreciate a couple of names of devices I could > purchase and try with all of these old utilities...
Names are meaningless. You can buy two identically branded and labelled devices and end up with two different chipsets. -- Grant Edwards grante Yow! I just had a NOSE at JOB!! visi.com
On 12 May 2006 07:54:21 -0700 in comp.arch.embedded, "Chris_99"
<cgruff@gmail.com> wrote:

>Gang: > >Now that all the cuel new laptops have no serial ports and no PCMCIA >card slot, and I am stuck haplessly with USB, does anyone have a good >experience with any USB (or fire-wire) serial devices? > >I have many legacy apps that want to talk to a UART real bad and the >quality of the driver would be the issue here. > >I would really appreciate a couple of names of devices I could purchase >and try with all of these old utilities...
Just a warning I haven't seen anyone else post yet: What kinds of apps are you taking about? If you're talking about simple serial communications, such as to a terminal or another computer, you're probably OK. USB has stabilized pretty. Everything I've tried in the last couple years, at least, even on Windoze boxes, has worked flawlessly. But if you've got something more esoteric, with tight timing requirements, such as a chip programmer or a dongle, something that isn't "pure", it may be that no USB device will work with it. For example, no USB serial or parallel port (that I'm aware of, at least) will allow you to toggle a control line faster than 500 Hz (the time base for USB frames is 1 ms). I only mention this because embedded programmers are more likely to have such applications than the general population. Regards, -=Dave -- Change is inevitable, progress is not.
"Dave Hansen" <iddw@hotmail.com> wrote in message 
news:vqf962pgkopaq77mibb65g7u39n7sdjolp@4ax.com...
> On 12 May 2006 07:54:21 -0700 in comp.arch.embedded, "Chris_99" > <cgruff@gmail.com> wrote: > >>Gang: >> >>Now that all the cuel new laptops have no serial ports and no PCMCIA >>card slot, and I am stuck haplessly with USB, does anyone have a good >>experience with any USB (or fire-wire) serial devices? >> >>I have many legacy apps that want to talk to a UART real bad and the >>quality of the driver would be the issue here. >> >>I would really appreciate a couple of names of devices I could purchase >>and try with all of these old utilities... > > Just a warning I haven't seen anyone else post yet: What kinds of > apps are you taking about? > > If you're talking about simple serial communications, such as to a > terminal or another computer, you're probably OK. USB has stabilized > pretty. Everything I've tried in the last couple years, at least, > even on Windoze boxes, has worked flawlessly. > > But if you've got something more esoteric, with tight timing > requirements, such as a chip programmer or a dongle, something that > isn't "pure", it may be that no USB device will work with it. For > example, no USB serial or parallel port (that I'm aware of, at least) > will allow you to toggle a control line faster than 500 Hz (the time > base for USB frames is 1 ms). > > I only mention this because embedded programmers are more likely to > have such applications than the general population.
Just to add a bit more to that: if these are *very* legacy, e.g. DOS with direct UART access, you're out of luck. Under Windoze, or any other OS with a hardware abstraction layer, it should be fine. Steve http://www.fivetrees.com
Chris_99 wrote:

> Gang: > > Now that all the cuel new laptops have no serial ports and no PCMCIA > card slot, and I am stuck haplessly with USB, does anyone have a good > experience with any USB (or fire-wire) serial devices? > > I have many legacy apps that want to talk to a UART real bad and the > quality of the driver would be the issue here. > > I would really appreciate a couple of names of devices I could purchase > and try with all of these old utilities... > > Thanks! > > Chris
Have a read of: http://www.dontronics-shop.com/product.php?productid=16139 you will see that this uses the FTDI chipset, is manufactured by Easysync, an FTDI company, and works where many others fail. Read the comments from customers on that page. Don... -- Don McKenzie E-Mail Contact Page: http://www.dontronics.com/e-mail.html Micro,TTL,USB to 1.5" color LCD http://www.dontronics.com/micro-lcd.html USB,RS232 or TTL to VGA Monitor http://www.dontronics.com/micro-vga.html World's smallest USB 2 TTL Conv http://www.dontronics.com/micro-usb.html
Chris_99 wrote:
> Gang: > > I would really appreciate a couple of names of devices I could purchase > and try with all of these old utilities... > > Thanks! > > Chris
I have had problems with the Prolific chip. It's a driver issue, not a chip issue, but Prolific provides both, so the difference is moot. (The driver has problems with certain function calls...) I don't see these issues with FTDI based units. And I've heard good things about the TI and SiLabs controllers. As someone pointed out you can find different chips in the same product from the same maker. IOGear changed chips a while back, and you can only tell them apart by the revision code. Expect to pay a bit more for one where you actually know what chip is in it. Hope that helps.
ghelbig@lycos.com wrote:
> Chris_99 wrote: >> Gang: >> >> I would really appreciate a couple of names of devices I could purchase >> and try with all of these old utilities... >> >> Thanks! >> >> Chris > > I have had problems with the Prolific chip. It's a driver issue, not a > chip issue, but Prolific provides both, so the difference is moot. > (The driver has problems with certain function calls...) > > I don't see these issues with FTDI based units. And I've heard good > things about the TI and SiLabs controllers. > > As someone pointed out you can find different chips in the same product > from the same maker. IOGear changed chips a while back, and you can > only tell them apart by the revision code. > > Expect to pay a bit more for one where you actually know what chip is > in it. > > Hope that helps. >
Do they still work. My IO Gear converters work fine.
> >> Gang: >> >> Now that all the cuel new laptops have no serial ports and no PCMCIA >> card slot, and I am stuck haplessly with USB, does anyone have a >> good experience with any USB (or fire-wire) serial devices? >> >> I have many legacy apps that want to talk to a UART real bad and the >> quality of the driver would be the issue here. >> >> I would really appreciate a couple of names of devices I could >> purchase and try with all of these old utilities... > > Just a warning I haven't seen anyone else post yet: What kinds of > apps are you taking about? > > If you're talking about simple serial communications, such as to a > terminal or another computer, you're probably OK. USB has stabilized > pretty. Everything I've tried in the last couple years, at least, > even on Windoze boxes, has worked flawlessly. > > But if you've got something more esoteric, with tight timing > requirements, such as a chip programmer or a dongle, something that > isn't "pure", it may be that no USB device will work with it. For > example, no USB serial or parallel port (that I'm aware of, at least) > will allow you to toggle a control line faster than 500 Hz (the time > base for USB frames is 1 ms).
If you are using a standard driver. Why not use more end points and a non standard protocol USB <-> JTAG Emulators certainly toggle the JTAG faster than 500 Hz You can get CDC (Communication Device Class) drivers for the AT91SAM7 series so you do not have to bother with special chips like FTDI to implement the serial port.
> > I only mention this because embedded programmers are more likely to > have such applications than the general population. > > Regards, > -=Dave
-- Best Regards, Ulf Samuelsson ulf@a-t-m-e-l.com This message is intended to be my own personal view and it may or may not be shared by my employer Atmel Nordic AB