[kismac] Re: GPS USB to Serial Compatibility

  • From: "N. Karras" <nkarras@xxxxxxxxxxx>
  • To: <kismac@xxxxxxxxxxxxx>
  • Date: Wed, 28 May 2003 22:41:12 -0400

500mA would be entirely exorbitant for that purpose.  When Mac OS X does =
not know the power requirements of a device, it always shows 500mA, the =
largest allowed under the USB spec.  Some devices are programmed with =
their power requirements along with device ad vendor ID's.  The power =
requirement as indicated by the computer is always either the value =
coded into the device, or 500mA under OS X, or Unknown on some OS's.  I =
personally have a USB keyboard I use on my PowerBook G4, which is rated =
for 35mA as shown on the bottom of the device, and in its manual, =
however Mac OS X shows 500mA.  Same with my 50mA Logitech TrackMan =
Marble USB trackball mouse.


----- Original Message -----=20
From: "Galen" <blueandwhiteg3@xxxxxxxxxxxx>
To: <kismac@xxxxxxxxxxxxx>
Sent: Monday, May 28, 2001 5:50 PM
Subject: [kismac] Re: GPS USB to Serial Compatibility

> A few replies to various posts:
> >>> What are the "right" drivers? The adapter came with nothing but =
> >>> Desktop software.
> >
> > You may run into a problem here...  IIRC, the Palm USB cable is just
> > that, a cable.  The Pal Pilot itself does all of the protocol
> > translation, similar to my Kodak Digital Camera which had a DIN-8
> > plug on the camera itself, and the a choice of a USB cable or a =
> > Serial cable to transfer images to your computer.  The Camera
> > actually has both interfaces built into it, and merely senses which
> > type of cable is attached to it.
> >
> > Also, IIRC, your standard Serial and USB do not use the same types =
> > data transmission (I.e. Tx, Rx, RTS, DTR pins going high/low to
> > represent data...) Which is why devices like the Keyspan USB-Serial
> > adaptor are still rather bulky.
> This thing is actually an adapter and, when I bought it, wasn't =
> cheap. It is a USB cable and a rather long box-like thing that has a=20
> standard serial port on it so I suspect it is at least partially a=20
> serial to USB adapter. It certainly has to change around some data for =

> the USB bus, and it seems to have a pretty good power requirement (500 =

> mA). Furthermore, it shows up on the USB chain without anything=20
> connected, so it at least has a full USB controller chipset on it.
> >> What are the "right" drivers? The adapter came with nothing but =
> >> Desktop software.
> >
> > There are quite a few drivers for various chipsets Serial to USB
> > connectors around. Just try them. You may find them listed under the
> > 'software' button or 'support' button of resellers. I have a few
> > drivers available for those interested.
> Can you give me some suggestions? I could just hit all the Mac OS X=20
> sites for serial to USB adapters, but I'm guessing there are half a=20
> dozen drivers or more available, some of which might conflict, so I'd=20
> probably have to install each one, test it, and then uninstall and=20
> repeat with the next driver. Or, if you have some interesting driver=20
> that isn't generally available, drop an email directly to me.
> ASP reports my adapter as follows:
> "USB Serial Adaptor"
> "Product ID 128 ($80)"
> "Serial Num 00337462"
> "Vendor Palm Computing, Inc."
> "Power (mA) 500"
> I'm not sure that's very helpful to anyone (it doesn't exactly specify =

> the chipset or anything like that) but it might be.
> I'm borrowing the GPS device (Garmin eTrex Vista) on thursday =
> (PST) and will give it a try. I'll let you know how it works. I'm just =

> borrowing it to give it a try, I am probably going to get a Garmin=20
> eTrex Legend GPS, the model just below the Vista (less memory, no=20
> electronic compass or barometric altimeter) with the same data=20
> interface, same design, etc.
> >
> >> P.S. Does anybody know why it sometimes takes up to a few days for =
> >> emails I send to this list to get sent out to everyone in the list? =
> >> this case, my original message was sent on the 26th at 2:25 AM but
> >> didn't get sent on the mailing list until the 28th at 12:25 am.
> >
> > Well, today you seem up to speed.
> This is quite odd. I'm on other lists (not at freelists) and I've =
> seen this happen and I've never seen any significant (>5 min) delay in =

> email getting to a person's inbox.
> Galen

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