USB-to-serial adapter (for GPS) and latest Prolific drivers

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John Navas

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Jan 8, 2007, 8:00:06 PM1/8/07
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NOTE: This is posted as a public service, _not_ spam -- I have no
connection to any of the companies below (except as a customer).


My two GPS units (Garmin and Magellan) have serial interfaces, and my
ThinkPad T41 notebook computer doesn't have a serial port, so I needed a
good USB-to-serial adapter.

My 1st try, a cheap generic adapter based on a "Huge Pine" chip,
purchased on eBay, was a complete failure -- Windows XP couldn't even
identify the hardware properly. In addition, the cable is relatively
long (over 3'), and the serial connector has attachment _screws_ rather
than (normally needed) attachment _nuts_. While I may have been unlucky
enough to get a defective unit, my research suggests that these "Huge
Pine" products are flaky, so I recommend avoiding them.

My 2nd try, a generic adapter based on the Prolific PL-2303 chip, was
successful -- it plays very well with Windows XP and with my GPS units.
(Prolific-based adapters are used by a number of major OEMs.) It's a
nice short (1') cable, and the serial connector has attachment nuts.
Prolific-based adapters are readily available on eBay, but I purchased
mine from local (San Francisco) vendor TekGems <http://tekgems.com/> for
$10 -- see <http://tekgems.com/Products/SBT-USC1M.htm>.

Although the adapter as supplied by TekGems comes with drivers on a mini
CD, later drivers for Windows (2.0.2.1, XP Logo Certified), Mac, and Red
Hat Linux, can be downloaded directly from Prolific. If you have
difficulty with the Prolific Taiwanese website in English (as I did),
use Google _cache_ from the Google search
<http://www.google.com/search?q=site%3Aprolific.com.tw+%22PL-2303+Software+and+Drivers%22>.
For Windows, run the Setup program _before_ attaching the adapter cable
and driver installation will be smooth and painless.

--
Best regards,
John Navas

G.T.

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Jan 9, 2007, 1:11:25 AM1/9/07
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And to add to this the Prolifics work great with OpenBSD. The driver is
included in the generic kernel.

Greg

--
"All my time I spent in heaven
Revelries of dance and wine
Waking to the sound of laughter
Up I'd rise and kiss the sky" - The Mekons

M.I.5¾

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Jan 9, 2007, 2:41:20 AM1/9/07
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"John Navas" <spamf...@navasgroup.com> wrote in message
news:3fn5q29t16mi5ai2k...@4ax.com...

USB to RS-232 adaptors seem to vary in their degree of compatibilty. I have
had no trouble with a no name cheapie off the internet (no idea about
anything else about it), others have had adaptors that work with some
peripherals but not others.


mi...@sushi.com

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Jan 9, 2007, 4:15:38 AM1/9/07
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Yes, I use the Prolific chip set on win2kpro and x64. However, I paid
$15 or so for a device from Airlink 101, and I had to wait for a sale.
;-) It's the same somewhat goofy teal color as the one on your
website. Not only does it run my GPS, it runs my scanners as well.
http://www.airlink101.com/products/ac-usbs.html

do...@87.usenet.us.com

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Jan 9, 2007, 3:37:44 PM1/9/07
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In sci.geo.satellite-nav John Navas <spamf...@navasgroup.com> wrote:
> My two GPS units (Garmin and Magellan) have serial interfaces, and my
> ThinkPad T41 notebook computer doesn't have a serial port, so I needed a
> good USB-to-serial adapter.

The pfranc adapter has been well received in this newsgroup.
http://www.pfranc.com/usb/usb.shtml
He mentions 'it should have "nuts not screws"' on the page.
It is $30, manufactured by MCT.

--
---
Clarence A Dold - Hidden Valley Lake, CA, USA GPS: 38.8,-122.5

Adrian Jansen

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Jan 9, 2007, 4:55:54 PM1/9/07
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We have less problems with USB-Serial devices using FTDI chips than
those based on the Prolific ones.
Especially when sending short messages back and forth between PC and
device, sometimes the Prolific ones need special setups buried way down
in the Windoze serial comms control system.

http://www.dontronics-shop.com/product.php?productid=16493&cat=265&page=1
is the device I prefer, based on 20-30 supplied to customers.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Design Engineer J & K Micro Systems
Microcomputer solutions for industrial control
Note reply address is invalid, convert address above to machine form.

John Navas

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Jan 9, 2007, 6:17:00 PM1/9/07
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On Wed, 10 Jan 2007 07:55:54 +1000, Adrian Jansen <adr...@qq.vv.net>
wrote in <12q83rv...@corp.supernews.com>:

>John Navas wrote:

>> My 2nd try, a generic adapter based on the Prolific PL-2303 chip, was
>> successful -- it plays very well with Windows XP and with my GPS units.

>> (Prolific-based adapters are used by a number of major OEMs.) ...

>> Although the adapter as supplied by TekGems comes with drivers on a mini
>> CD, later drivers for Windows (2.0.2.1, XP Logo Certified), Mac, and Red

>> Hat Linux, can be downloaded directly from Prolific. ...

>We have less problems with USB-Serial devices using FTDI chips than
>those based on the Prolific ones.
>Especially when sending short messages back and forth between PC and
>device, sometimes the Prolific ones need special setups buried way down
>in the Windoze serial comms control system.

Were you using older Prolific driver versions? I've now run a fair
number of torture tests against my Prolific PL-2303 with the Windows XP
driver 2.0.2.1, and all were passed successfully. If you're got
something legitimate that you think will cause it to fail, I'd be happy
to try it. (My posting email address is valid.)

Bruce

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Jan 10, 2007, 8:15:47 AM1/10/07
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"John Navas" <spamf...@navasgroup.com> wrote in message
news:3fn5q29t16mi5ai2k...@4ax.com...

There are also PCMCIA serial adapters. More pricey than the USB adapters
but they may be more likely to work with multiple device types.


Dave Martindale

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Jan 10, 2007, 1:55:34 PM1/10/07
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"Bruce" <bru...@cox.net> writes:

>There are also PCMCIA serial adapters. More pricey than the USB adapters
>but they may be more likely to work with multiple device types.

Unfortunately, they have their own obsolescence problem: new laptops
tend to come with Express Card slots and don't support PCMCIA any more.

Dave

Jack Erbes

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Jan 10, 2007, 2:23:59 PM1/10/07
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Dave Martindale wrote:

Oh no! Another much beloved I/O bites the dust!

That means I'll eventually lose the use of my two PCMCIA RS-232 cards
and my PCMCIA RS-422 card. Not that I've used them recently...

Oh yeah, and my PCMCIA Token Ring adapters too!

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

Adrian Jansen

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Jan 10, 2007, 4:13:38 PM1/10/07
to

I cant give you specific driver versions, most of the problems were
reported from remote customers, and may not even have been with XP. We
deal with people who use anything from '98 up. All I can say is that
when we suggested they buy adapters using FTDI chips, most of the
problems ceased.
The Prolific units I tested personally could be got to work, by
adjusting the timeouts and buffer sizes in the comms setup, but I am not
certain some customers followed our recommendations.
However we may have had a special case, since we were sending short
binary packets in both directions. Typical GPS use, where its just one
data stream in one direction is not likely to cause much problem.

Bruce

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Jan 10, 2007, 7:26:53 PM1/10/07
to

"Jack Erbes" <jack...@adelphia.net> wrote in message
news:JsGdnZYhMd3NoDjY...@adelphia.com...

I'm thinkin you can safely toss those token ring adapers :)

Thanks Dave for the heads up on the Express Card stuff. I suppose that in a
few years there will be people asking for PCMCIA to Express Card adapters!


M.I.5¾

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Jan 11, 2007, 3:52:29 AM1/11/07
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"Jack Erbes" <jack...@adelphia.net> wrote in message
news:JsGdnZYhMd3NoDjY...@adelphia.com...
> Dave Martindale wrote:
>
>> "Bruce" <bru...@cox.net> writes:
>>
>>
>>>There are also PCMCIA serial adapters. More pricey than the USB adapters
>>>but they may be more likely to work with multiple device types.
>>
>>
>> Unfortunately, they have their own obsolescence problem: new laptops
>> tend to come with Express Card slots and don't support PCMCIA any more.
>>
>> Dave
>
> Oh no! Another much beloved I/O bites the dust!
>
> That means I'll eventually lose the use of my two PCMCIA RS-232 cards and
> my PCMCIA RS-422 card. Not that I've used them recently...
>
> Oh yeah, and my PCMCIA Token Ring adapters too!
>

Does anyone know where I can get spare tokens?


Dave Martindale

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Jan 11, 2007, 4:02:51 PM1/11/07
to
"M.I.5¾" <no....@no.where.NO_SPAM.co.uk> writes:

>> Oh yeah, and my PCMCIA Token Ring adapters too!

>Does anyone know where I can get spare tokens?

eBay!

Seriously, there must be lots of spare tokens just floating around the
ether these days. Try just setting up a token ring and see if it
attracts any of them.

Dave

Jack Erbes

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Jan 12, 2007, 8:38:18 AM1/12/07
to
Dave Martindale wrote:

I'm sure there are some dinosaur geeks still willing to argue the
superiority of Token Ring networking and with their homes or workplaces
still running a TR network at 4-16mbs.

As it happens, I have a couple of 3Com 3C389 PCMCIA TR adapters still in
their sealed boxes. Another 50 years or so and those will probably be
worth something to a museum of networking or something. :>)

BillW50

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Jan 12, 2007, 4:35:48 PM1/12/07
to
"Adrian Jansen" <adr...@qq.vv.net> wrote in message
news:12qaloo...@corp.supernews.com

> I cant give you specific driver versions, most of the problems were
> reported from remote customers, and may not even have been with XP. We
> deal with people who use anything from '98 up. All I can say is that
> when we suggested they buy adapters using FTDI chips, most of the
> problems ceased.
>
> The Prolific units I tested personally could be got to work, by
> adjusting the timeouts and buffer sizes in the comms setup, but I am
> not certain some customers followed our recommendations.
> However we may have had a special case, since we were sending short
> binary packets in both directions. Typical GPS use, where its just
> one data stream in one direction is not likely to cause much problem.

I don't know who MCT is, but that is the author of my drivers for my Art
USB Bay unit. Seems to work well with most things. Dirt Cheap for a port
replicator. Many can be found for 10 bucks or less.

--
Bill

Don McKenzie

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Jan 13, 2007, 6:41:44 AM1/13/07
to
Adrian Jansen wrote:

> We have less problems with USB-Serial devices using FTDI chips than
> those based on the Prolific ones.
> Especially when sending short messages back and forth between PC and
> device, sometimes the Prolific ones need special setups buried way down
> in the Windoze serial comms control system.
>
> http://www.dontronics-shop.com/product.php?productid=16493&cat=265&page=1
> is the device I prefer, based on 20-30 supplied to customers.

Hi Adrian,

Thanks for the mention. Got myself a pda/gps for Christmas, found it
works fine from the window seat of a commercial jet at 35K feet, however
the Points Of Interest, or anything else for that matter, between Alice
Springs and Darwin are few and far between. :-)

So I logged onto this group for the first time just now, to learn a
little more about GPS, as a newbie.

And saw your mention of my products. Would just like to enlarge, we have
a world wide money back guarantee on these USB-RS232 units. Simply
return it in a re-sellable condition for a full refund.

User feed back about GPS at:
http://www.dontronics-shop.com/product.php?productid=16139


Don...

--
Don McKenzie
E-Mail Contact Page: http://www.dontronics.com/e-mail.html

Crystal clear, super bright OLED LCD (128x128) for your microcontroller.
Simple serial RX/TX interface. Many memory sizes.
http://www.dontronics-shop.com/product.php?productid=16460

Ian Singer

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Jan 13, 2007, 9:28:15 AM1/13/07
to
Don McKenzie wrote:


> Thanks for the mention. Got myself a pda/gps for Christmas, found it
> works fine from the window seat of a commercial jet at 35K feet, however
> the Points Of Interest, or anything else for that matter, between Alice
> Springs and Darwin are few and far between. :-)

Airline crews told me in the US its illegal to use on board. Also I know
for a fact that it will not work itside the cockpit of a 747 as the
heater wires block the signal.

Ian Singer

--


=========================================================================
See my homepage at http://www.iansinger.com
hosted on http://www.1and1.com/?k_id=10623894
All genealogy is stored in TMG from http://www.whollygenes.com
Charts and searching using TNG from http://www.tngsitebuilding.com
I am near Toronto Canada, can I tell where you are from your reply?
=========================================================================

Dale DePriest

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Jan 13, 2007, 11:10:54 AM1/13/07
to

Ian Singer wrote:
> Don McKenzie wrote:
>
>
>> Thanks for the mention. Got myself a pda/gps for Christmas, found it
>> works fine from the window seat of a commercial jet at 35K feet,
>> however the Points Of Interest, or anything else for that matter,
>> between Alice Springs and Darwin are few and far between. :-)
>
> Airline crews told me in the US its illegal to use on board. Also I know
> for a fact that it will not work itside the cockpit of a 747 as the
> heater wires block the signal.
>
> Ian Singer
>

It is certainly not illegal in the sense that there is a law against
their use. Some airlines have rules that prohibit the use of a GPS in
flight but there are also many airlines that permit it above 10000 feet.

http://gpsinformation.net/airgps/gpsrfi.htm


--
_ _ Dale DePriest
/`) _ // http://users.cwnet.com/dalede
o/_/ (_(_X_(` For GPS and GPS/PDAs

Barry Watzman

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Jan 13, 2007, 2:46:27 PM1/13/07
to
I doubt if a GPS receiver in an airliner will work at all; you would
need line-of-sight from the GPS antenna to at least three satellites
through a window, and that seems unlikely. But Ian is correct, there is
not a law against it. However individual airlines are fee to make up
their own rules about use of electronics onboard their aircraft, and
those policies then have the force of law on board those particular flights.

Doug

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Jan 13, 2007, 3:00:35 PM1/13/07
to
Sorry, you are wrong. Used a Garmin GPS V on a trip to France a few years
ago, in a window seat it worked quite well. It was very nice to see Chatres
from above, it was the first stop on our trip, we got there later that
evening.
Doug.

"Barry Watzman" <Watzma...@neo.rr.com> wrote in message
news:45a93717$0$9572$4c36...@roadrunner.com...

Don McKenzie

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Jan 13, 2007, 3:50:12 PM1/13/07
to
Doug wrote:

Not only did it work next to a window, when I appeared to have it locked
on, it also worked tucked into the pocket of the seat in front of me, in
such a position, that I could see it at all times without the need to
touch it.

Darwin to Alice Springs is 1306KM (810 Miles), and apart from the
airports, the only mapping (TomTom) that I could see was the Stuart HWY
and many "Desert Track(s)". As I said earlier, there isn't much out
there. A few un-named dry lakes showed up along the way.

Aircraft for this short hop was a small Boeing 717, and the unit I used
is a PDA/GPS HP RX-5765. Electronic devices can be used on domestic
Qantas flights during the flight, but not during take off and landing.

"Show GPS Status" which indicates sat. position and strength, was alive
90% of the flight time.

Speed indication on the GPS was around 860 to 870kph during the flight.

I then flew from Alice Springs to Adelaide, stopped, then flew from
Adelaide to Melbourne. These two legs were in 737's, however I wasn't
able to duplicate my previous success.

Found when I got home, I couldn't get a good GPS signal at all. Not
until I plugged it into power, so the lack of signal in the 737's may
have been a low battery problem.

Next flight, I will start off at the populated end of things, and with a
full battery.

Be interested in others results during flights.
Perhaps an external antenna with a window suction cup may be an idea. :-)

What would Qantas say? :-)

Ahhhh!!!! The sky is the limit.

Adrian Jansen

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Jan 13, 2007, 6:34:00 PM1/13/07
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Don McKenzie wrote:

Yes, I often use a Garmin Etrex on flights in commercial aircraft, 737,
767 etc. Works fine initially up against a window. Once you get a
lock, the front seat pocket usually works ok. I usually get smiles from
the cabin crew - "Dont you trust the pilot ?"

peter

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Jan 13, 2007, 7:18:59 PM1/13/07
to
Don McKenzie wrote:
> > "Barry Watzman" <Watzma...@neo.rr.com> wrote in message
> > news:45a93717$0$9572$4c36...@roadrunner.com...
> >
> >>I doubt if a GPS receiver in an airliner will work at all; you would
> >>need line-of-sight from the GPS antenna to at least three satellites
> >>through a window, and that seems unlikely. But Ian is correct, there is
> >>not a law against it. However individual airlines are fee to make up
> >>their own rules about use of electronics onboard their aircraft, and
> >>those policies then have the force of law on board those particular

> Be interested in others results during flights.


> Perhaps an external antenna with a window suction cup may be an idea. :-)

I've never had any trouble getting a signal lock with my eMap when
sitting in a window seat. I usually hold the unit right by the window
until it gets a lock and can then frequently leave it sitting on the
edge of the seat tray.
On a recent flight I could only get a middle seat but I had my external
antenna along. I was a bit hesitant about asking the passenger in the
window seat for permission to place the antenna there, but he seemed
friendly enough so I decided to risk it. Turns out he was a pilot and
therefore very familiar with GPS and immediately agreed to let me run
the antenna cable from the window and looped around the seat tray
supports to keep it out of the way. That provided excellent
full-strength signals on at least 5 - 6 satellites throughout the
flight (top speed was 703 mph when we hit a good tailwind just before
descending into Minneapolis).


>
> What would Qantas say? :-)

Qantas used to be one of the GPS-friendly airlines, but recently they
included a note on their website indicating that use during flight was
not allowed. I sent them an email urging them to reconsider the policy
and they said they'd look into it but I never heard back after that.

Ness net

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Jan 13, 2007, 7:26:18 PM1/13/07
to
You are absolutely wrong....

I personally have used a GPS in flight many times.
(granted a window seat really helps)

As have many others here...


"Barry Watzman" <Watzma...@neo.rr.com> wrote in message news:45a93717$0$9572$4c36...@roadrunner.com...

JNavas

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Jan 14, 2007, 5:09:02 PM1/14/07
to
Adrian Jansen wrote:
> John Navas wrote:

> > Were you using older Prolific driver versions? I've now run a fair
> > number of torture tests against my Prolific PL-2303 with the Windows XP
> > driver 2.0.2.1, and all were passed successfully. If you're got
> > something legitimate that you think will cause it to fail, I'd be happy
> > to try it. (My posting email address is valid.)

> I cant give you specific driver versions, most of the problems were
> reported from remote customers, and may not even have been with XP. We
> deal with people who use anything from '98 up. All I can say is that
> when we suggested they buy adapters using FTDI chips, most of the
> problems ceased.
> The Prolific units I tested personally could be got to work, by
> adjusting the timeouts and buffer sizes in the comms setup, but I am not
> certain some customers followed our recommendations.
> However we may have had a special case, since we were sending short
> binary packets in both directions. Typical GPS use, where its just one
> data stream in one direction is not likely to cause much problem.

My "torture tests" were considerably more rigorous than that, and
exhibited no problems. Again, I'd be happy to run additional tests if
you think you've got something legitimate that you think will cause it
to fail.

Best regards,
John Navas

Adrian Jansen

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Jan 15, 2007, 4:41:52 PM1/15/07
to
I cant easily extract a test sequence out of what I used, it relies on a
PC at one end and a dedicated instrument at the other. The PC side is
easy enough, but reproducing what the instrument sends and expects, at
the same timing, would be quite difficult. But basically if you sent
message frames of around 20-40 bytes at 38400 baud ( including nulls )
backwards and forwards between two PCs, with a USB adapter in the chain,
at about 10 frames per second, and never lost a byte, then I would
regard that as a pretty good test.

John Navas

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Jan 18, 2007, 12:13:57 AM1/18/07
to
On Tue, 16 Jan 2007 07:41:52 +1000, Adrian Jansen <adr...@qq.vv.net>
wrote in <12qnt9q...@corp.supernews.com>:

>JNavas wrote:

>> My "torture tests" were considerably more rigorous than that, and
>> exhibited no problems. Again, I'd be happy to run additional tests if
>> you think you've got something legitimate that you think will cause it
>> to fail.

>I cant easily extract a test sequence out of what I used, it relies on a

>PC at one end and a dedicated instrument at the other. The PC side is
>easy enough, but reproducing what the instrument sends and expects, at
>the same timing, would be quite difficult. But basically if you sent
>message frames of around 20-40 bytes at 38400 baud ( including nulls )
>backwards and forwards between two PCs, with a USB adapter in the chain,
>at about 10 frames per second, and never lost a byte, then I would
>regard that as a pretty good test.

One of my tests was FTP transfer using a serial V.90 POTS modem with a
port speed of 115 Kbps over a 48K dial-up connection. That's
bi-directional transfer with short packets in one direction and long
packets in the other direction. No evidence of any serial errors. That
would seem to fit the bill pretty well -- no?

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