CAI 302 date problem

[Bernie[_4_]]

I flew yesterday (26 October) and had two hours, later I used the
Cambridge utility on my PDA to download the flight log from the
Cambridge 302.

First thing I noticed was that the utility said the flight was 111
hours long, and that the date of the flight was 21 October.

I later checked the log file in See You and it thinks it was 21 Oct.
also.

I then noticed that I had not reset the date in my PDA after replacing
the battery a few weeks back, it thought it was 2002.

However I can't see how the date in the secure .igc file could or
should be affected by that.

The only other thing I can think is that when I last flew (17th Oct ),
I flipped the master switch off rather than doing an orderly shutdown
on the 302.

Any ideas?

[Darryl Ramm]

On Oct 26, 4:08*pm, Bernie > wrote:
> I flew yesterday (26 October) and had two hours, later I used the
> Cambridge utility on my *PDA to download the flight log from the
> Cambridge 302.
>
> First thing I noticed was that the utility said the flight was 111
> hours long, and that the date of the flight was 21 October.
>
> I later checked the log file in See You and it thinks it was 21 Oct.
> also.
>
> I then noticed that I had not reset the date in my PDA after replacing
> the battery a few weeks back, it thought it was 2002.
>
> However I can't see how the date in the secure .igc file could or
> should be affected by that.
>
> The only other thing I can think is that when I last flew (17th Oct ),
> I flipped the master switch off rather than doing an orderly shutdown
> on the 302.
>
> Any ideas?

Is the C302 internal battery OK? Does the data in the file look OK
when you look at the flight in SeeYou? Did the Cambridge utility
complain about any security failures? I'm curious and will look at
the file - if you want to attach the file to an email and send to me
(or try posting it on OLC).


Darryl

[Bernie[_4_]]

Thanks Darryl,
I will post the file on the OLC when I get home from work this
afternoon, and email it to you.

The file looks complete in See You. The CAI utility did not complain
about it's integrity.

We also wondered about the internal battery in the 302, but after
checking the manual I
cannot even find any suggestion that one exists. I know that the
earlier Cambridge models
had them. The manual states " Flash memory is used for firmware as
well as flight logs. "

Regards, Bernie.

[Tim Taylor]

On Oct 26, 5:08*pm, Bernie > wrote:
> I flew yesterday (26 October) and had two hours, later I used the
> Cambridge utility on my *PDA to download the flight log from the
> Cambridge 302.
>
> First thing I noticed was that the utility said the flight was 111
> hours long, and that the date of the flight was 21 October.
>
> I later checked the log file in See You and it thinks it was 21 Oct.
> also.
>
> I then noticed that I had not reset the date in my PDA after replacing
> the battery a few weeks back, it thought it was 2002.
>
> However I can't see how the date in the secure .igc file could or
> should be affected by that.
>
> The only other thing I can think is that when I last flew (17th Oct ),
> I flipped the master switch off rather than doing an orderly shutdown
> on the 302.
>
> Any ideas?

First is the name of the file correct? Not the date but the actual
name of the file, should be a 0AQxxxx file name. If that is correct
the 302 is fine and it is the date on the PDA that is the problem.
The PDA will store the file under the current date it thinks it is.
If the file name is different then it is likely a 302 problem.

[Bernie[_4_]]

Thanks Tim.
I will check the file name tonight when I get home. (I'm in Australia,
we are working right now!)

I would have thought that the date in an .igc file would have been
derived from the GPS satellite data.

Certainly, when I copied the file from the PDA to my PC, it was
timestamped 2002, as per the PDA.
If the .igc file also said 2002, I would tend to agree with you. But
just 4 days earlier?

Regards, Bernie.

[JS]

Mr. Baer, from 13,000km away I believe Mr. Taylor has the answer.
Jim

[Darryl Ramm]

On Oct 26, 5:57*pm, JS > wrote:
> Mr. Baer, from 13,000km away I believe Mr. Taylor has the answer.
> Jim

Ah? SeeYou and any other sane software will derive the date/duration
of the file from the IGC file HFDTE record and B record timestamps and
does not care what a file is named. And no software will care about
the filesystem time stamp on a file. What is going on should be
obvious within the IGC file.

If the download utility did not complain about security fail then the
battery backup should be fine.

Darryl

[Bernie[_4_]]

On Oct 27, 12:07*pm, Darryl Ramm > wrote:
> On Oct 26, 5:57*pm, JS > wrote:
>
> > Mr. Baer, from 13,000km away I believe Mr. Taylor has the answer.
> > Jim
>

Hey Jim,
not sure that I agree yet, wishing I had the file here at work to take
a look at now!
Coming to Keepit this year? We're there for the NSW State titles in a
month or so.
BB.

[Darryl Ramm]

On Oct 26, 11:05*pm, JS > wrote:
> Tim's scenario still seems best to me. Look at your PDA's system date
> and time.
> * See if you can beat this: One of my 1993 flight logs out of Tonopah
> had one data point in 1946. At least we could blame that on the space
> aliens in nearby Area 51.
> * (If the weather's anything like at the Club and Sports Nationals
> last November, you're in for a good competition. I won't make it to
> Lake Keepit in November, but rented the Duo in mid- January.)
> Jim
>
> On Oct 26, 6:21*pm, Bernie > wrote:
>
> > Hey Jim,
> > not sure that I agree yet, wishing I had the file here at work to take
> > a look at now!
> > Coming to Keepit this year? We're there for the NSW State titles in a
> > month or so.
> > BB.
>
>

Nope Jim sorry. The issues really are separate from the PDA clock. e.g
the file name encoding just could not be driven by the PDA system
clock, it is driven by data inside the C302. You just cannot design a
system that creates different file names depending on what it is
downloaded to . What flight of the day each IGC file is is determined
from information inside the C302 - it has to be. And a file system
timestamps means nothing to an IGC file.

Bernie - The IGC file as emailed to me failed validation with the
official IGC valicam2.exe utility, but quite possibly that just
handling or email attachment problems. Can you run the valicam2.exe
utility on the files on your PC. If they fail try downloading the IGC
files again. You could also try downloading with ConnectMe and see
what happens then.

---

But I have a suspicion the file is might actually not be corrupted.
And if so, all that is going on is the IGC file simply has a large
jump in time in the B-record. This happens as the GPS acquires a 3D
fix and I am guessing the time up to that point has been driven by the
(confused) battery backed real time clock. Although how exact this is
implemented I am not sure. How long it takes to get the GPS time
depends on how many satellites are in view and is not really the same
as getting a geometry fix, but its likely in the hand full of minutes
for an old receiver like in the C302.

The file shows

Date header
HFDTE211010 == 21st October 2010 (date of first B record entry)

First B record

B1233283402657S15041334EV0005500000000000000128

ie. that is for 12:33:28 UTC (on 21st October 2010 from header
above) . You only have a 2D GPS fix (V letter code in B record).

Then you get a bit further down you get a time jump

B1235393402657S15041334EV0060200000000004000128 (i.e. 12:35:39 UTC)
B0204073404298S15039998EA0061800625000000030000 (i.e. 02:04:07 UTC in
what should be 3 seconds (the log rate) later)

Note the roll from 2D to 3D fix (V to A letter codes) coincident with
the time jump. The B-record jump cannot tell us how many days the date
has jumped, software will assume its jumped to the next 24 hour day.

I can imagine reasons to want the recorder to start even if it does
not have a valid 3D fix. And I could imagine that the assumption is
made that the real time clock is valid, but later if it gets bumped by
the GPS clock it does not matter as this happening in the file will be
obvious. Any IGC folks want to comment?

--

BTW SeeYou seems to ignore these before the time jump fixes and it
scores a sensible flight duration of 02:00:44. I've not messed around
trying to work out how it knows to do this (could be the 3D fix, could
be it detects the time jump and drops all earlier B-records). But it
shows the flight date as 21st October 2010 because that's the date in
the HFDTE header.

--

When was the C302 internal battery last replaced? I believe this
should be done each time you calibrate the device. If the battery is
OK (the C302 shows "Seal OK" and you don't get security fail errors on
download) then the real time clock should have been updated from the
last GPS data. The next time you power on the GPS see if it acquires a
fix faster, if its still very slow something may be wrong (check the
antenna). But if its what I suspect there is a good chance the problem
will just have gone away next time you fly. (Thanks to Tim Newport-
Peace who pointed out the existence of the real time clock in the C302
on r.a.s before.).


Darryl

[Bernie[_4_]]

Thank you for your assistance and analysis Darryl.

I ran the valicam2 utility against the igc file and it checks OK:
Log Data Integrity OK
Signature Data Integrity OK
Security OK

The internal battery has never been replaced, as the unit is just over
two years old (Last calibrated 9/5/08 at the factory)
The C302 showed 'Seal OK' when I turned it on, pretty sure of that,
but will check again next time.

I'll check the antenna connection before powering on next time, and
hope that you are correct and this was a on-off error.

Regards, Bernie

[Bernie[_4_]]

> I'll check the antenna connection before powering on next time, and
> hope that you are correct and this was a on-off error.

I mean a 'one off' error !

[Bernie[_4_]]

> Hi Darryl,
>
> Have a look in the IGC file for the Geodetic datum in use (HFDTM
> record). If this is not 100, WGS84 then the battery in the GPS25 engine
> is suspect (maybe it's suspect anyway). This battery recharges in use,
> but if it goes flat, the RTC stops :=<
>
> This is not the same battery as that which maintains the volatile RAM.
>
> Tim.

Hi Tim,
from the igc file; that field appears to be blank:

HFGIDGLIDERID:VH GAH
HFDTM100GPSDATUM:
HFRFWFIRMWAREVERSION:F2.6

Regards, Bernie.

[Bernie[_4_]]

>
> Hi Tim,
> from the igc file; that field appears to be blank:
>
> HFGIDGLIDERID:VH GAH
> HFDTM100GPSDATUM:
> HFRFWFIRMWAREVERSION:F2.6
>
> Regards, Bernie.

Just checked some much older files (2008, 209) and the field is also
blank, and the logger was working fine then!

[Bernie[_4_]]

On Oct 27, 9:46*pm, Bernie > wrote:
> > Hi Tim,
> > from the igc file; that field appears to be blank:
>
> > HFGIDGLIDERID:VH GAH
> > HFDTM100GPSDATUM:
> > HFRFWFIRMWAREVERSION:F2.6
>
> > Regards, Bernie.
>
> Just checked some much older files (2008, 209) and the field is also
> blank, and the logger was working fine then!

And looked at a file from a completely different 302 in another
aircraft, it also has:
HFDTM100GPSDATUM:

[Bernie[_4_]]

Thanks Darryl (and Tim, and Tim).
We'll see how it goes next flight.
Regards, Bernie.

[Bernie[_4_]]

On Oct 28, 6:54*am, Bernie > wrote:
> Thanks Darryl (and Tim, and Tim).
> We'll see how it goes next flight.
> Regards, Bernie.

Everything was A-OK today....... thanks guys.

[[email protected]]

Dear All
The CLEAR LOG command in See You Moile works very easily so I wonder can SEE You mobile also e used to set the date and time in the Camridge 302 at the start of a days flying? Anyone know what the command is and correct syntax for the date and time?
See You mobile retains the command in a drop down menu so it would e easy to do each day

Thanks for your help
Martin

[[email protected]]

Google on the 302 Data Port User's Guide. I don't see any way to set a date shown in that manual. It does mention another document called the Secure BIOS User's Guide that may include such details but I've never been able to find a copy of that document anywhere.

RS

On Tuesday, May 3, 2016 at 2:46:06 AM UTC-5, wrote:
> Dear All
> The CLEAR LOG command in See You Moile works very easily so I wonder can SEE You mobile also e used to set the date and time in the Camridge 302 at the start of a days flying? Anyone know what the command is and correct syntax for the date and time?
> See You mobile retains the command in a drop down menu so it would e easy to do each day
>
> Thanks for your help
> Martin
>

[Tim Newport-Peace[_3_]]

At 13:07 03 May 2016, wrote:
>Google on the 302 Data Port User's Guide. I don't see any way to set a
>dat=
>e shown in that manual. It does mention another document called the
>Secure=
> BIOS User's Guide that may include such details but I've never been able
>t=
>o find a copy of that document anywhere.
>
>RS
>
>On Tuesday, May 3, 2016 at 2:46:06 AM UTC-5, wrote:
>> Dear All
>> The CLEAR LOG command in See You Moile works very easily so I wonder
can
>=
>SEE You mobile also e used to set the date and time in the Camridge 302
at
>=
>the start of a days flying? Anyone know what the command is and correct
>sy=
>ntax for the date and time?
>> See You mobile retains the command in a drop down menu so it would e
>easy=
> to do each day=20
>>=20
>> Thanks for your help
>> Martin =20
>>
>
>
From what you say, it would seem that your problem lies in the Real Time
Clock on the GPS25 engine and not in Cambridge hardware.

Phil Schlosser at Clearnav should be able the replace the RTC battery and
reset the clock.

The problem is that the RTC forget which epoch (1024 weeks) it is in, the
rest of the Time comes from satellites.

Time to spend a little money.

[Tango Eight]

The fix is a new GPS card, as discussed in other threads.

http://www.clearnav.net/main/cn-service.html

best,

Evan Ludeman for CNi

[David Kinsell[_2_]]

On Tue, 03 May 2016 13:41:11 +0000, Tim Newport-Peace wrote:

> At 13:07 03 May 2016, wrote:
>>Google on the 302 Data Port User's Guide. I don't see any way to set a
>>dat=
>>e shown in that manual. It does mention another document called the
>>Secure=
>> BIOS User's Guide that may include such details but I've never been
>> able
>>t=
>>o find a copy of that document anywhere.
>>
>>RS
>>
>>On Tuesday, May 3, 2016 at 2:46:06 AM UTC-5, wrote:
>>> Dear All The CLEAR LOG command in See You Moile works very easily so I
>>> wonder
> can
>>=
>>SEE You mobile also e used to set the date and time in the Camridge 302
> at
>>=
>>the start of a days flying? Anyone know what the command is and correct
>>sy=
>>ntax for the date and time?
>>> See You mobile retains the command in a drop down menu so it would e
>>easy=
>> to do each day=20
>>>=20
>>> Thanks for your help Martin =20
>>
>>
> From what you say, it would seem that your problem lies in the Real Time
> Clock on the GPS25 engine and not in Cambridge hardware.
>
> Phil Schlosser at Clearnav should be able the replace the RTC battery
> and reset the clock.
>
> The problem is that the RTC forget which epoch (1024 weeks) it is in,
> the rest of the Time comes from satellites.
>
> Time to spend a little money.

You can buy a much more capable logger for a lot less than it costs to
repair the 302's, at least in the U.S.

[Tomasz Sielicki]

On Wednesday, May 4, 2016 at 8:26:46 PM UTC-5, David Kinsell wrote:

>
((SNIP))

> You can buy a much more capable logger for a lot less than it costs to
> repair the 302's, at least in the U.S.

When I looked at page 17 of XCSoar Manual:

Supported external devices and features,

I knew I want to keep my CAI302. Next to LX Vario it's the one that has ALL columns "checked": Declaration, Remote ctrl., Download, Airspeed, Vario, Baro altitude, Wind, G-Sensor. It's so much more than just a logger. I sent both 302+303 to Gary Kammerer at ClearNav and got them back after 9 days.

Tomasz