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Magellan WAAS issue is solved


trainlove

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Merry Christmas One and All.

I have solved the WAAS issue for Magellan receivers. The solution,

which actaully was figured out by qwert1515, should work for all

Meridian GPSr's, no matter what firmware version you have.

 

I believe the solution will work for all SportTrak's since it appears

that their firmware has a lot in common with the Meridians, at least

in the WAAS arena.

 

I have yet to see if the Explorists are also similar.

 

I know that the Map330 and Map330Pro should also work, I had a copy

of that firmware hanging around for some reason.

 

Details will follow when I'm thoroughly satisfied with repeatability

and documentation issues.

 

But it will require you to modify your own firmware, using nothing

more complicated than WordPad and the Windows Calculator. I don't

feel comfortable supplying 'modified' firmware and Magellan, whoever

owns Magellan today, probably wouldn't like it even though they

consider all these GPSr's as Legacy Unsupported products.

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This is great news, thanks. Should breathe new life into the eBay market for Merdians, SporTraks, and M330s :laughing:

...I have yet to see if the Explorists are also similar...

Most Explorists can be fixed with firmware updates -- even if you have to hunt/scrounge for the files. So for most a hand-patch wouldn't be needed.

 

But for those that don't have firmware updates available, your patch may not be possible if it's based on hand-editing the hex (s-record) files of older Magellan models. Explorist firmware is distributed as binary, for completely different processor chips.

Edited by lee_rimar
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Great news. My Meridian was used during the WAAS satellite change, so it still gets the WAAS signals and processes them. However, this will be good if I ever have to do a reset.

 

My Explorist 500 has the first European firmware, so it also receives WAAS. I understand that there is a second firmware that upgrades later serial numbers of Explorists. Go to the Yahoo user group to determine which to use based on your serial number for the 500 and 600.

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I'm still working on editing and finalizing it...
Looks do-able by hand - and someone may be able to find a way to automate that for various firmware revisions.

 

After you patched one up without telling it the correct longitude for the new sats, how long does it take to initialize and start getting corrections (as compared to a comparable unit that DOES know the correct longitude(s))?

Edited by lee_rimar
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trainlove:

Again, great detective work.

Status report: Here's what my Meridian ver 5.35 was looking for:

Pos   PRN	Long	Sat				Status 
1	 122	-54	 OLD WAAS AOR-W	 Switched OFF 
2	 120	-15	 AOR-E EGNOS		OK 
3	 131	+64	 OLD IOR EGNOS	  Switched OFF
4	 134	+178	OLD WAAS POR	   Switched OFF
5	 129	+140	OLD MTSAT-1R	   Switched OFF (?)
6	 137	+140	MTSAT-2			OK (?)

Magellan appears to have "guessed" right on ARO-E EGNOS. Info is a bit hard to come by on the MTSAT birds (Japanese version of WAAS), but I think the above is correct on the MTSAT birds.

 

Now - to decide what to put where, and try it. I do travel internationally, so I intend to implement a version with the current EGNOS and MTSAT birds, but I think I will be conservative and try a US version first. I'm not too concerned about the GPSr looking for something it can't find. I suspect it takes and uses what it finds first (or finds two?). Also, from what I read today, EGNOS is soon going (or has gone) operational in Europe, including IONO (for use in Europe, of course).

Edited by Klemmer & TeddyBearMama
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Trainlove: You have put together the information very nicely, much better than I could have.

 

There are a few things I want to add, that might make the editing a little bit easier:

 

If you were able to see at least one of the old WAAS satellites then all you have to do is change one (or both) of the old satellites in the firmware to the new ones and when you turn the GPS on the current WAAS almanac will be downloaded (Which contains both of the current WAAS satellites and their locations)

 

The old WAAS satellites were: PRN 122 [HEX 7A], PRN 134 [HEX 86]

 

The new WAAS satellites are: PRN 135 [HEX 87], PRN 138 [HEX 8A]

 

So you can change the 7A to 87 and the 86 to 8A (At the correct location in the firmware) and the GPS will get the correct WAAS almanac.

 

Example: If you were able to see the old 122 satellite and you only change the 122 satellite to the new 135 satellite, and then let the unit download the new almanac, it will pick up the 138 satellite and the locations.

 

If you are on the satellite map when the almanac finishes downloading you will see the WAAS satellites "W" s jump to their correct locations.

 

In the process of figuring this out I wrote many edited firmware files to my GPS and accidentally even wrote a binary version of the firmware instead of the S-Code and the "PWR - GOTO - ESC" combination always allowed me to write a new firmware file to the unit. (Hold the "GOTO - ESC" buttons down and then press PWR)

 

When I update the firmware from the SD card, most of the time I loose the units Basemap, but if I use MagUp (Serial cable) in Expert mode I have not lost the Basemap.

 

There is also a way to update the units normal almanac and I will see if Trainlove wants to put a "How To" together.

Edited by qwert1515
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Tried this with my 2 Meridian units. I still get the "120" and "122" in the hidden menu #3. One thing I notice now but did not remember before is the "120" and "122" come and go, blinking in and out like it's searching for something different (a almanac update perhaps? I sure hope so.).

 

It did look like the firmware uploaded (neither bricked on me using the SD to upload the firmware and I did not loose my basemap in either unit), but I don't see any change and don't see WAAS averaging either.

 

There is one issue I'm not real sure about. The checksums. In the directions it talks about recalculating the checksums, but later it says the checksum does not matter. I did not change the checksums Did I miss something?

 

I tried modding Meridian Gold firmware 5.41 and the structure was identical to the directions.

 

I also tried modding Platinum firmware 5.40 with the fixes. I did find the hex data in question was in a different location in the file for the Platinum, but the structure was the same.

 

Has anybody else gotten this work on a Gold or Platinum? Just curious, but is there some reason not to post a fixed and working copy of the firmware somewhere? 5.41 for Gold is 5.41 for all the gold units, same for Platnium, so one working copy could be cloned by many.

 

And did I miss something?

Edited by Roo & the Bears
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Tried this with my 2 Meridian units. I still get the "120" and "122" in the hidden menu #3. One thing I notice now but did not remember before is the "120" and "122" come and go, blinking in and out like it's searching for something different (a almanac update perhaps? I sure hope so.).

 

 

I found the same thing on a Meridian Gold. I then cleared the memory using MENU - SETUP - CLEAR MEMORY - ALL after which the unit shuts down by itself. I then turned the unit back on and let it acquire a lock and within 10 - 12 minutes it had a WAAS lock and was receiving data from both PRN-135 and PRN-138 (hidden menu #3). Looks like Magellan had us clearing the memory when doing a firmware update for a reason.

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Has anybody else gotten this work on a Gold or Platinum? Just curious, but is there some reason not to post a fixed and working copy of the firmware somewhere? 5.41 for Gold is 5.41 for all the gold units, same for Platnium, so one working copy could be cloned by many.

 

And did I miss something?

 

I have been able to get the fix to work on a Meridian Gree, Gold and Color units. Same data structure - just in slightly different locations in each file.

 

(I know - I should have put this all in one posting :ph34r: )

Edited by Frodo_Underhill
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I wondered if leaving the longitude untouched in my first try contributed to the delay in success (or failure).

 

I went and found the longitude for the two current WAAS sattelites:

 

Galaxy 15 (135) is at 133*W or FF7B hex

Anik F1R (138) is at 107.3*W or FF95 hex

 

So I tried to mod the firmware with these two locations and reflashed. Still shows 120 & 122 in menu 03.

 

I'll let 'em both run a while and see if they update.

Edited by Roo & the Bears
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I was also a little confused by trainlove explaining the checksum type, then saying it didn't matter. I felt like playing with it, so after looking for a simple checksum program, but not finding one I liked, I wrote one in Excel. PM me if you want it.

 

Thanks for the reminder on doing a clear all. I guess if you don't clear, it uses what was in memory, rather than going to the firmware.

 

P.S. I'm OK with modifying firmware data in a unit I own (not code, really); but I'm not comfortable with sending out modified firmware. A bit risky / legally gray area, IMO.

Edited by Klemmer & TeddyBearMama
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I should have refreshed the computer screen. I did not see the reply about clearing the memory.

 

I tried that on the Gold and it WORKED!!!!! I see 138 with "FIX" in menu 03, and it is searching for 135. It found 138 within seconds after I flashed the firmware with the current longitude added to the firmware (I had uploaded it to the SD before I read the clear memory messages). I reset the Platinum and it's still searching, but it does show it is searching for the new WAAS 135 & 135 units, so I'm going to update the longitude and reflash it. Apparently if you input the longitude data it makes a difference.

 

Thanks to all for this fix.

 

I still love my Meridians (now if I could find a source for a display for the Platinum, the backlight is out but otherwise it's a perfect unit). And for some reason the Platnium always "says" it has greater accuracy than the Gold in side by side comparision. Not sure if it's true of just what the unit says however.

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Both units now show "FIX" status on the new WAAS birds. Neither is showing WAAS Averaging yet. I'm assuming it still needs to download the updated almanac so I'm going to let them run a while on the deck.

 

Adding the longitude data made a world of difference in the time it took to find the new WAAS sats after the memory was cleared. With the correct data is was almost instant, went from searching to binary (data?) to FIX. I had also manually entered my GEO location exactly instead of the "by state" on the clear memory re-initialization. I suspect this also contributed to the fast FIX (I had manually entered it before updating the longitude data and it was still searching).

 

I did not edit the checksum data. Just the WAAS id info and longitude. I suspect it would have found the new sats just find with the id info only, the longitude just makes the initial search faster.

 

Now I just have to re-enter the personalized "welcome" screen I had set up in the old firmware (a project for later)

Edited by Roo & the Bears
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You the MAN trainlove! Platinum ver 5.35 alive, BOTH WAAS birds locked up! Woo-Hoo!

 

Woodstramp: The ONE big thing the Meridians (and their close relatives) have going for them is the almost unlimited number of files of 500 each waypoints files you can load up. I typically use it for benchmark hunting, and often have over 20,000 benchmarks I can chose from (in SoCal) - although they are in 500 waypoint chunks. Even on a 256 MB SD card, I'm still only using about half of it, including Topos (fair quality) of CA & AZ. I also have Worlwide Basemaps I can cut & load, when I travel. Very handy. There are newer units that are better at other things (I have several), but the good ol' MeriPlat is still better at a few things. Sorta like a '57 Chevy - a classic. Now we have re-furbed the carb!

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Two more things I want to mention:

 

After uploading the new firmware you can reset the memeory by holding the "Nav - Goto" keys and press the power button to bring up the hidden menu, and then enter 30 (Clear Memory) and press enter.

 

Also I HIGHLY recommend if you have a Meridian basic (The unit I have, other Meridians might have this issue) that you DO NOT upload the firmware from the SD card because every time I have lost the Basemap and it can be hard to resend it. I have only been able to resend after leaving the batteries out of the unit for a little while, and removing the SD card, resetting the memory has not allowed me to send the Basemap with the SD card or over the Serial cable.

Edited by qwert1515
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I did not edit the checksum data. Just the WAAS id info and longitude. I suspect it would have found the new sats just find with the id info only, the longitude just makes the initial search faster.

 

Changing the longitudes should not make a difference because the longitudes are used only to display the location on the satellite screen and to tell the unit that the satellite should be visible at your location.

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Qwert1515:

Interesting on the Longitudes. That will be helpful outside the US, to know if I should even bother. Thanks. Glad I put them all in (including EGNOS & MTSAT).

 

I have upgraded (or "same" graded) my Platinum several (3 or 4?) times, and not had any problem with losing the basemap (of course, I have it backed up, just in case).

Edited by Klemmer & TeddyBearMama
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Back from a weekend trip.

 

I'll answer a few questions here.

 

1. Yes the regular GPS satellite almanac appears too, that's why a cold start from a completely memory clear takes a while, the satellites today are not exactly where they would be if you project their positions forward from the orbital elements of some 4+ years ago. Check that celestrak site for archived almanacs and play with satellite tracking programs for fun. Yes, geeky.

Changing any of this really should not matter at all. All the GPS satellites (but not the NMEA) broadcast their elements, and each broadcast the whole almanac of 32 elements over time.

I have figured out how to turn a NASA 2 line satellite element, or a SEM or YUMA element set into a NMEA set, that's what I thinkwould be needed in the firmware.

A $PMGNCMD,ALMANAC command returns up to 32 elements sets, for satellites that have been received.

Here is one line for satellite 25, one earlier satellite was not yet knows when I did this after a reset.

$PMGNALM,31,24,25,1512,00,6060,7B,1070,FFFFFD46,A10D0A,CD6B1B,D728DD,517F70,000,000*71

Things like this do appear in the firmware.

I'll make my info on this available sometime. But I'm spending my time making my writeup more understandable to everyone, reguardless of their computer skills.

 

2. One should only need to change Longitudes, if say you expect to travel to Europe and want EGNOS over there. We on the East Coast of the USA can see PRN120, and the GPS will look for that since it's above our horizon, even if there are real live birds here. I'm not exactly sure but I think the firmware looks sequentially through that list of 6 satellites for any above the horizon. I had to change PRN120 from Weat -15 (FFF1) to East +15 (0F) so it would not show up at all. If I ever go to Europe it will show up. Others have not had to do this and it seems that if one new satellite is seen then the rest is known, that has not happened for me.

 

3. Magellan sucks in that there can only be 6 WAAS satellites. The FAA system actually allows for something like 30, and right now there are 7 listed at celestrak. I think Garmins are better in this respect, they search all possible WAAS/EGNOS/MSAS satellites, wether they are above your horizon or not, until they find one or more.

 

4. SD card vs serial, I've not clobbered my basemap either way. But I have clobbered the firmware a couple times using the SD method.

 

5. I would post 'modified' firmware versions if there were not too many Magellan Models, and so many versions of firmware, and it were not a copyright issue. But mostly I don't want to go to prison.

If it were as easy as a 'patch' I would provide that, but as many know, the WAAS section of all the firmware at different addresse.

 

6. Some people have reported that their GPS's still look for 120 and 122, even after removing those. A memory reset will clear that up. I've spelled that out in the latest little edit to VERSION 1 of my page. LOL.

Edited by trainlove
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I haven't made any changes yet, so, just checking. In this string, have I selected the right numbers for the birds?

 

S3192D1BD3DC230A230F23142319231E23232328232D233223374C

S3192D1BD3F00000FF7B8700FFF1780000408300FF958A00008CA9

S3192D1BD4048100008C8900000018181818181818181818080830

 

F7=247

78=120

83=131

8A=138

A9=169

89=137

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F7=247

A9=169

Those are WRONG.

 

Please read the writeup a few more times. If you have not read it in a few days, it's been made a little more understandable in the last couple days.

You have chosen a checksum instead of a satellite in one place.

And you have chosen part of a Longitude instead of a satellite in the other place, and gotten that botched too. Pairs of characters, not individual characters, ABCDEFGHIJ is mentally thought of as AB CD EF GH IJ and can't ever be thought of as A BC DE FG HI J

 

I've corrected your highlights

S3 19 2D1BD3DC 230A230F23142319231E23232328232D23322337 4C

S3 19 2D1BD3F0 0000FF7B8700FFF1780000408300FF958A00008C A9

S3 19 2D1BD404 8100008C89000000181818181818181818180808 30

 

87Hex=135

81=129

If these represent the firmware you alread have then you already have WAAS.

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F7=247

A9=169

Those are WRONG.

 

Please read the writeup a few more times. If you have not read it in a few days, it's been made a little more understandable in the last couple days.

You have chosen a checksum instead of a satellite in one place.

And you have chosen part of a Longitude instead of a satellite in the other place, and gotten that botched too. Pairs of characters, not individual characters, ABCDEFGHIJ is mentally thought of as AB CD EF GH IJ and can't ever be thought of as A BC DE FG HI J

 

I've corrected your highlights

S3 19 2D1BD3DC 230A230F23142319231E23232328232D23322337 4C

S3 19 2D1BD3F0 0000FF7B8700FFF1780000408300FF958A00008C A9

S3 19 2D1BD404 8100008C89000000181818181818181818180808 30

 

87Hex=135

81=129

If these represent the firmware you alread have then you already have WAAS.

 

Thanks, that's why I asked. My Merigold was on when the change in satellites took place, which may explain why I already have WAAS (and I already knew that part) This was purely academic and I wanted myself (and others) to be able to see a real example because I didn't think I had selected the correct pairs.

 

Now, here's a question. If I re-initialize the Merigold without updating the firmware, would I lose WAAS?

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A reminder (or maybe new info for some) for those here that didn't follow some discussions on the Meridian Yahoo group:

 

1) Certain Magellan Meridians (Gold / Platinum?), and certain firmware revisions (I don't know which) have a nasty habit of very slowly losing some sort of internal time sync. As has been commented before, Magellan messed up the time on these units badly.

 

2) The result of 1) above can (sometimes?) result in increasingly inaccurate positioning data, with a consistent offset in one direction (sorry don't remember the direction). My Meridian got out to about a consistent 40 feet or so (even with WAAS active).

 

3) The fix for 2) above is to perform a SETUP/CLEAR MEMORY/ALL (leading to new Initialization and new time synchronization).

 

4) If you had active (functioning) WAAS before doing 3) above, because you used it during the satellite "change over period (summer 2007, I believe), you will "lose" the WAAS (if you have factory firmware), because the unit will default to what is hard coded in the firmware.

 

This is what happened to me, and I had my WAAS-less Platinum for a year or so. Typical accuracy was 25 feet or so. Now we have the cure for the loss of WAAS!

 

So - if you have a Meridian with working WAAS, you might have slowly deteriorating accuracy (you can check it at a known good "adjusted" benchmark, or some other way). If your displayed time is way off from reality, that is a clue your accuracy might be going haywire. Now that I have the WAAS code fix, I plan to do a CLEAR ALL if my MeriPlat time is off from reality by more than maybe 10 seconds (or check its accuracy).

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Thanks to all for the work on this. It is a great utility for what remains a very usable GPSr.

 

I have had the Meridian Green for 6 years. It was on during the satellite change in 2007, and kept WAAS reception. Prior to this time, it had the time clock problem. After the WAAS satellites changed, it had a very accurate time showing, usually withing a couple of seconds from true time. I was using the firmware 4.03.

 

After seeing this thread, I decided to try it. I figured it might be needed in the future anyway. The latest firmware for the Meridian Green/Yellow is the 4.06, which I had. The relevant file is MGPS406.HEX.

 

Original lines in MGPS406.HEX ( In Notepad, I did a "CTRL F", and searched for 00FFCA to find the line):

S3192D141CC8231E23232328232D233223370000FFCA7A00FFF1BD

S3192D141CDC78000040830000B28600008C8100008C8900000018

 

These lines after the changes:

S3192D141CC8231E23232328232D233223370000FF7B8700FFF1BD

S3192D141CDC780000408300FF958A00008C8100008C8900000018

 

I used the serial port method and it worked quick and well. Unit gets both WAAS very strongly (my location helps.) The accuracy always is very good at GPS site benchmarks, and would often show 10 or 7 feet EPE. I will test it again soon.

 

Note: Someone at the Yahoo Meridian group posted a complete modified firmware 5.40 file, but it appears they have pulled it.

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Note: Someone at the Yahoo Meridian group posted a complete modified firmware 5.40 file, but it appears they have pulled it.

I would expect Magellan to send out the hounds to any site that actually supplies 'modified' firmware due to copyright issues. They are very active in making sure no site has any BaseMaps. But I consider a BaseMap to be useless without a GPS, so why make it hard for people to get them?

 

As for the timing issue and consistancy in offset in one direction. I never detected that the error was in one specific direction. I got the impression it was always in whatever direection you were walking. I.E. You always overshoot a waypoint, hense the name 'rubberbanding error'.

 

Another indication of the timing being off, besides and http://www.time.gov/ or wwv shortwave, is to use secret menu [01] at the bottom of the screen are 2 lines, the last line alternates every 10 seconds, if it says BADRTCR and a number other than 0 your timing is off, it can sometimes correct itself to a smaller number but BADRTCR itself never goes away unless you do a memory clear all. You should normally see Tt 0 and something.

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My previously WAASless Sportrak Color is alive and well again thanks to the hard work of Trainlove, qwert1515 et al. Thank you so much!

I wasn't able to figure out how back-up my basemap but I just closed my eyes, held my breath and tried the fix. It worked first try. Basemap is intact.

 

Thanks again.

Edited by Navi-Gatr
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As the owner of a Gold and a Plat; I've got a little work to do.

I think I need to update the Gold's firmware anyways, it's my little used backup/kid's unit.

 

So, if I've got this right; all I really need to do is change about 4 characters in the firmware? (skipping the longitudes)

 

ie this part

So you can change the 7A to 87 and the 86 to 8A

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So you can change the 7A to 87 and the 86 to 8A

And perhaps perform a memory clear all operation depending on what firmware you previously had and/or what model number you are doing it on...

Hundreds of satisfied people so far.

Zero, that I know of, who have had an unrecoverable problem.

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I didn't even have to open up a hex file. Over at the Yahoo Meridian group there are fixed files to download. It basically took me all night last night; but I got the WAAS situation fixed. I did have to do the clear all memory, initialize and calibrate the compass on the Plati.

What I thought was a Gold is actually a Yellow - I ended up crashing it about four times and really thought I had bricked it.

I ended up losing the base map and the only one I could find online was the European basemap.

If anyone knows where to find or has the Green/Yellow 2meg basemap -I'd really appreciate it.

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I didn't even have to open up a hex file. Over at the Yahoo Meridian group there are fixed files to download. It basically took me all night last night; but I got the WAAS situation fixed. I did have to do the clear all memory, initialize and calibrate the compass on the Plati.

What I thought was a Gold is actually a Yellow - I ended up crashing it about four times and really thought I had bricked it.

I ended up losing the base map and the only one I could find online was the European basemap.

If anyone knows where to find or has the Green/Yellow 2meg basemap -I'd really appreciate it.

Didn't I say to back up your own basemap? You only have yourself to blame.

Published firmware on that web site might make Magellan Lawyers try to shut down that site. Just like they have shut down many sites that have ever posted basemaps. There are some people who have many basemaps. I have many and might send you one, but I need to know what that filename was on your Green/Yellow which you thought was a Gold (any why do you mention Platinum which is the only unit with a Compass?)

WHAT UNIT DO YOU NEED A BASEMAP FOR? Everyone else who might want to help you needs to know the truth.

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Didn't I say to back up your own basemap? You only have yourself to blame.

 

Yes, I could not back it up. Yes, agreed.

 

Published firmware on that web site might make Magellan Lawyers try to shut down that site. Just like they have shut down many sites that have ever posted basemaps. There are some people who have many basemaps. I have many and might send you one, but I need to know what that filename was on your Green/Yellow which you thought was a Gold (any why do you mention Platinum which is the only unit with a Compass?)

 

I don't know what basemap filename I had. I believe that if Magellan won't support us, then supporting each other is good. I have two Meridians - a Platinum and a Yellow that until two days ago I thought was a Gold.

 

WHAT UNIT DO YOU NEED A BASEMAP FOR? Everyone else who might want to help you needs to know the truth.

 

I thought I clearly stated what unit I needed a basemap for. On my Yellow, when the basemap was lost on a stuck upload and I finally got the unit powered up again; it would not funcition and was stuck on an invalid basemap page. Once I got it working with the EU basemap, my topo detail maps worked fine.

 

 

I was given a tip on where to find a North American basemap that works.

Thanks to everyone for their help - I now have two working WAAS enabled Meridians.

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MY, MY, MY . . . Magellan has posted on their site an official firmware update for giving the

"Legacey" 'XL' . . . WAAS capabilities. "A day late, and a dollar short!" I can only hope that

QWERTY's & trainloves efforts have spurred an effort in the "Great non-communicators"

Mayhaps Mitac is going to really run w/the ball after picking it up, things may get interesting,

but I doubt it, we'll see.

 

ver. 2.11

 

I wonder if it has the "missing menus" that the Euro update provided?

If anyone's BOLD enough to try it, please give a report.

 

Norm

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