USB to Serial Adapters

[MegaScott]

To change your comm port number on a Prolific usb-serial converter-

Go to the "Control Panel",
Double click on "System"
On the "Hardware" tab, click on "Device Manager"
Click on the +sign next to "ports", or double click on "ports".
Double click on "Prolific USB-to-Serial Comm Port (Comx)".
Click on the "Port settings" tab,
Click on the "Advanced" button.
In Advanced you'll see a pulldown to be able to set the port at whatever you want!! All the way to 256. I'd pick a low number like com3. Click "ok" a couple times and that should be good. You can change this on the fly without rebooting, so watch out. You should probably only change the port number before you run any Comm programs, like Megatune or Hyperterm.

[mbohn]

To change your comm port number on a Prolific usb-serial converter-...................

Thanks, Scott. Worked fine. We'll see if it stays that way.

1/2/05 update. Well, it didn't. Most recent startup it was a com7. Never seen that particular com port before!

[Daryl]

ThankYou, Scott!!!
I have been trying to figure this out for a week!!
I'm learning computer at the same time I'm learning EFI and Ignition. It gets a little overwhelming at times.
Thanks for the step by step. Much appreciated!

Daryl

[MegaScott]

Thanks! happy To help

Have a very Happy and Successful New Year!!

[philhoward]

Cross Post which may be of inerest on USB-Serial converters, and a cheap supply thereof...

http://www.msefi.com/viewtopic.php?t=5521

Megascott's methos of changing the assigned COM port is how i've changed mine, and it works fine. The only problem I ever had was putting the converter into a different USB port occasionally; it kept wanting to reinstall the driver. I just have to remember to put it in the same hole everytime (ooh err!!)

[MegaScott]

Megascott's methos of changing the assigned COM port

It's not my way, it's one just one way of changing the driver settings in all windows devices. These options are provided courtesy of the driver programmer.

Cheers!!

[daxtojeiro]

Hi all,
well Ive broken my old 486 and had to get a new laptop, and yes it hasnt got a serial port, so Ive bought an adaptor and I get comms with MS but it breaks every so often, screen goes to zero and MT bleeps then all is well again. I can't not send info, I can recieve it OK, and send small dialog boxes, but anything like a VE table, etc, it just fails, any ideas? I did grab your program that you put up on here Eric about viewing USB ports, is that still needed as I can soon send a screen shot of that,
Phil

[efahl]

On Fri, January 7, 2005 9:28 am, daxtojeiro said:

> got a serial port, so Ive bought an adaptor and I get comms with MS but it
> breaks every so often, screen goes to zero and MT bleeps then all is well
> again.

Phil,

That's probably MT resetting the comm link, which it does after
about 50 IO failures.

> I can't not send info, I can recieve it OK, and send small dialog
> boxes, but anything like a VE table, etc, it just fails, any ideas? I did

Yeah, that's the traditional way for USB to fail. Try messing with
the interWriteDelay and writeBlocks parameters, if you've got
writeBlocks on, turn it off and set interWriteDelay to 1. If it's
on, turn it off and set delay to 10 or something.

> grab your program that you put up on here Eric about viewing USB ports, is
> that still needed as I can soon send a screen shot of that,

My intent with that was to look at as many configurations as possible
to try to deduce patterns in the installations that failed, but I
never got enough data to make it worthwhile (and I mostly fixed the
problem around build 330), so it doesn't do me much good. You might
want to poke through its screens and see if there is anything it can
tell you, though, to set buffer sizes smaller or time delays shorter
on the USB driver...

Eric


--
Eric Fahlgren http://www.not2fast.com/



(posted by email)

[daxtojeiro]

Hi Eric,
well I turned the writeBlocks off and set the interWrite Delay to 15 and it now sends msq's etc, so thats great, thanks for that, but I still get this over flow, what is causing it? Seems to me that its better if you dont move the mouse, as soon as the PC tries to do anything it seems to fail. I can play with the buffers but not sure what Im doing in there,
Phil

[walkerm]

I have the later Prolific PL-2303X variant. There is a difference between the older PL-2303 chip which affects Linux users using the std kernel driver. Unfortunately the Product and Vendor IDs are the same for both chip versions, so depending on your Linux driver code it will report a successful load and attachment of the PL-2303. But when you come to use it it's useless.

I fixed this by upgrading Gentoo to the latest dev kernel - 2.6.9. I have seen some patches for 2.4, but I don't know if they work. Best to try the latest 2.4 kernel if you have the problem.

IIRC, the only way to deduce you have the X variant is to check the bMaxPacketSize0 and see if it gives 0x40 (64). Then you probably have one.

This cheap (£10GBP) device is working for me on both XP and Linux so far, but I haven't done any high throughput comms yet. I'll update if it fails at all.

Hope this helps. And here's my usbview output:-

Device Descriptor:
bcdUSB: 0x0110
bDeviceClass: 0x00
bDeviceSubClass: 0x00
bDeviceProtocol: 0x00
bMaxPacketSize0: 0x40 (64)
idVendor: 0x067B
idProduct: 0x2303
bcdDevice: 0x0300
iManufacturer: 0x01
iProduct: 0x02
iSerialNumber: 0x00
bNumConfigurations: 0x01

ConnectionStatus: DeviceConnected
Current Config Value: 0x01
Device Bus Speed: Full
Device Address: 0x01
Open Pipes: 3

Endpoint Descriptor:
bEndpointAddress: 0x81
Transfer Type: Interrupt
wMaxPacketSize: 0x000A (10)
bInterval: 0x01

Endpoint Descriptor:
bEndpointAddress: 0x00
Transfer Type: Control
wMaxPacketSize: 0x0507 (1287)
wInterval: 0x0202
bSyncAddress: 0x40

Endpoint Descriptor:
bEndpointAddress: 0x00
Transfer Type: Control
wMaxPacketSize: 0x0000 (0)
wInterval: 0x0000
bSyncAddress: 0x07