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All
As some of you know, I have what I call a "GPS Simulator" which is an ATmega88 I programmed to send a NMEA string with the $GPRMC sentence, and it also has a realtime clock which updates correctly in the $GPRMC, and produces a 1pps signal output. Using this I can model different settings, baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and which didn't, there seemed to be a consensus opinion that GPS modules having very short (microseconds) pulse widths on the 1pps signal, do not work properly in v2.02a. So I have set my simulator with a very short pulse width, less than 1us. Using this setting I can see the seconds jump sometimes in 2 second jumps. So I am able to reproduce the same problem some GPS modules show.?
Next I printed out my code and stared at it all week on the train to and from work. ?I came up with a strategy for fixing it. This evening I tried the strategy. It works! In my simulator at least! Everything is ticking away here nicely with 1 minute frame, message "E" in FSK/CW with speed 006, GPS on, and < 1us pulse width. Heartbeat is beating nicely and 125MHz calibration has occurred, as have time setting and Maidenhead locator.
I will now send a v2.03 chip (as it will be called) to Eddie G3ZJO (proud Trimble owner) and Andy G0FTD (UP502 GPS) and Tony G0BZB (EM406). If you three can try it and it works on all three then I think this will be excellent progress indeed, maybe finally the Ultimate2 GPS issues will be over and we'll have widespread compatibility with most GPS modules.?
Fingers crossed...
73 Hans G0UPL ?
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Sounds very good to me.
Will this still be happy with the Adafruit unit and the 100mS pulse width?
73 Keith.
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All
As some of you know, I have what I call a "GPS Simulator" which is an ATmega88 I programmed to send a NMEA string with the $GPRMC sentence, and it also has a realtime clock which updates correctly in the $GPRMC, and produces a 1pps signal output. Using this I can model different settings, baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and which didn't, there seemed to be a consensus opinion that GPS modules having very short (microseconds) pulse widths on the 1pps signal, do not work properly in v2.02a. So I have set my simulator with a very short pulse width, less than 1us. Using this setting I can see the seconds jump sometimes in 2 second jumps. So I am able to reproduce the same problem some GPS modules show.?
Next I printed out my code and stared at it all week on the train to and from work. ?I came up with a strategy for fixing it. This evening I tried the strategy. It works! In my simulator at least! Everything is ticking away here nicely with 1 minute frame, message "E" in FSK/CW with speed 006, GPS on, and < 1us pulse width. Heartbeat is beating nicely and 125MHz calibration has occurred, as have time setting and Maidenhead locator.
I will now send a v2.03 chip (as it will be called) to Eddie G3ZJO (proud Trimble owner) and Andy G0FTD (UP502 GPS) and Tony G0BZB (EM406). If you three can try it and it works on all three then I think this will be excellent progress indeed, maybe finally the Ultimate2 GPS issues will be over and we'll have widespread compatibility with most GPS modules.?
Fingers crossed...
73 Hans G0UPL ?
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On 27/06/2013 23:13, Hans Summers wrote: If you three can try it and it works on all three then I think this will be excellent progress indeed, maybe finally the Ultimate2 GPS issues will be over and we'll have widespread compatibility with most GPS modules. Yey, that will be fun.I shall mug every passing Postman for the next few days.:-) Indeed that would be excellent progress, I do hope that widespread compatibility is achieved. 73 Eddie G3ZJO
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That's great news Hans.
I solved the problem with my Up501 gps by adding ferrite beads on every lead connected to the gps. It would seem that gps modules do not like being close to rf fields. It may be worth mentioning this on the site in case some still experience problems with modules that are U2 compatible.
73's
de Andy
------------------------------
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On Thu, Jun 27, 2013 3:13 PM PDT Hans Summers wrote: All
As some of you know, I have what I call a "GPS Simulator" which is an
ATmega88 I programmed to send a NMEA string with the $GPRMC sentence, and
it also has a realtime clock which updates correctly in the $GPRMC, and
produces a 1pps signal output. Using this I can model different settings,
baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and which didn't, there
seemed to be a consensus opinion that GPS modules having very short
(microseconds) pulse widths on the 1pps signal, do not work properly in
v2.02a. So I have set my simulator with a very short pulse width, less than
1us. Using this setting I can see the seconds jump sometimes in 2 second
jumps. So I am able to reproduce the same problem some GPS modules show.
Next I printed out my code and stared at it all week on the train to and
from work. I came up with a strategy for fixing it. This evening I tried
the strategy. It works! In my simulator at least! Everything is ticking
away here nicely with 1 minute frame, message "E" in FSK/CW with speed 006,
GPS on, and < 1us pulse width. Heartbeat is beating nicely and 125MHz
calibration has occurred, as have time setting and Maidenhead locator.
I will now send a v2.03 chip (as it will be called) to Eddie G3ZJO (proud
Trimble owner) and Andy G0FTD (UP502 GPS) and Tony G0BZB (EM406). If you
three can try it and it works on all three then I think this will be
excellent progress indeed, maybe finally the Ultimate2 GPS issues will be
over and we'll have widespread compatibility with most GPS modules.
Fingers crossed...
73 Hans G0UPL
|
I can see it now... Ultimate 3 including a real time clock like this one... Tell the new U3 your 10 character grid and watch it keep the transmitter on time...
Paul KE7HR
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--- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
All
As some of you know, I have what I call a "GPS Simulator" which is an
ATmega88 I programmed to send a NMEA string with the $GPRMC sentence, and
it also has a realtime clock which updates correctly in the $GPRMC, and
produces a 1pps signal output. Using this I can model different settings,
baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and which didn't, there
seemed to be a consensus opinion that GPS modules having very short
(microseconds) pulse widths on the 1pps signal, do not work properly in
v2.02a. So I have set my simulator with a very short pulse width, less than
1us. Using this setting I can see the seconds jump sometimes in 2 second
jumps. So I am able to reproduce the same problem some GPS modules show.
Next I printed out my code and stared at it all week on the train to and
from work. I came up with a strategy for fixing it. This evening I tried
the strategy. It works! In my simulator at least! Everything is ticking
away here nicely with 1 minute frame, message "E" in FSK/CW with speed 006,
GPS on, and < 1us pulse width. Heartbeat is beating nicely and 125MHz
calibration has occurred, as have time setting and Maidenhead locator.
I will now send a v2.03 chip (as it will be called) to Eddie G3ZJO (proud
Trimble owner) and Andy G0FTD (UP502 GPS) and Tony G0BZB (EM406). If you
three can try it and it works on all three then I think this will be
excellent progress indeed, maybe finally the Ultimate2 GPS issues will be
over and we'll have widespread compatibility with most GPS modules.
Fingers crossed...
73 Hans G0UPL
|
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Show quoted text
On 27 June 2013 23:13, Hans Summers <hans.summers@...> wrote:
?
All
As some of you know, I have what I call a "GPS Simulator" which is an ATmega88 I programmed to send a NMEA string with the $GPRMC sentence, and it also has a realtime clock which updates correctly in the $GPRMC, and produces a 1pps signal output. Using this I can model different settings, baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and which didn't, there seemed to be a consensus opinion that GPS modules having very short (microseconds) pulse widths on the 1pps signal, do not work properly in v2.02a. So I have set my simulator with a very short pulse width, less than 1us. Using this setting I can see the seconds jump sometimes in 2 second jumps. So I am able to reproduce the same problem some GPS modules show.?
Next I printed out my code and stared at it all week on the train to and from work. ?I came up with a strategy for fixing it. This evening I tried the strategy. It works! In my simulator at least! Everything is ticking away here nicely with 1 minute frame, message "E" in FSK/CW with speed 006, GPS on, and < 1us pulse width. Heartbeat is beating nicely and 125MHz calibration has occurred, as have time setting and Maidenhead locator.
I will now send a v2.03 chip (as it will be called) to Eddie G3ZJO (proud Trimble owner) and Andy G0FTD (UP502 GPS) and Tony G0BZB (EM406). If you three can try it and it works on all three then I think this will be excellent progress indeed, maybe finally the Ultimate2 GPS issues will be over and we'll have widespread compatibility with most GPS modules.?
Fingers crossed...
73 Hans G0UPL ?
|
Well done Hans....
Will be nice to get my Trimble unit working again...
Great stuff
Philip G4JVF
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--- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
All
As some of you know, I have what I call a "GPS Simulator" which is an
ATmega88 I programmed to send a NMEA string with the $GPRMC sentence, and
it also has a realtime clock which updates correctly in the $GPRMC, and
produces a 1pps signal output. Using this I can model different settings,
baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and which didn't, there
seemed to be a consensus opinion that GPS modules having very short
(microseconds) pulse widths on the 1pps signal, do not work properly in
v2.02a. So I have set my simulator with a very short pulse width, less than
1us. Using this setting I can see the seconds jump sometimes in 2 second
jumps. So I am able to reproduce the same problem some GPS modules show.
Next I printed out my code and stared at it all week on the train to and
from work. I came up with a strategy for fixing it. This evening I tried
the strategy. It works! In my simulator at least! Everything is ticking
away here nicely with 1 minute frame, message "E" in FSK/CW with speed 006,
GPS on, and < 1us pulse width. Heartbeat is beating nicely and 125MHz
calibration has occurred, as have time setting and Maidenhead locator.
I will now send a v2.03 chip (as it will be called) to Eddie G3ZJO (proud
Trimble owner) and Andy G0FTD (UP502 GPS) and Tony G0BZB (EM406). If you
three can try it and it works on all three then I think this will be
excellent progress indeed, maybe finally the Ultimate2 GPS issues will be
over and we'll have widespread compatibility with most GPS modules.
Fingers crossed...
73 Hans G0UPL
|
Good morning Hans (and all),
I am still working towards getting my U2 kit built and on the air
and I have been taking note of the discussions around GPS and new
versions of firmware.
At the moment I am hesitant to order new chips as I am waiting to
see where things fall. However, I have to ask, is the hex file
available of the new versions for those of use capable of
programming a new cpu to be able to do so?
cheers, Graham ve3gtc
On 13-06-27 10:13 PM, Hans Summers wrote:
toggle quoted message
Show quoted text
All
As some of you know, I have what I call a "GPS
Simulator" which is an ATmega88 I programmed to send a NMEA
string with the $GPRMC sentence, and it also has a realtime
clock which updates correctly in the $GPRMC, and produces a
1pps signal output. Using this I can model different settings,
baud rates, and 1pps pulse widths.
From the comments on which GPS modules worked and
which didn't, there seemed to be a consensus opinion that GPS
modules having very short (microseconds) pulse widths on the
1pps signal, do not work properly in v2.02a. So I have set my
simulator with a very short pulse width, less than 1us. Using
this setting I can see the seconds jump sometimes in 2 second
jumps. So I am able to reproduce the same problem some GPS
modules show.?
Next I printed out my code and stared at it all
week on the train to and from work. ?I came up with a strategy
for fixing it. This evening I tried the strategy. It works! In
my simulator at least! Everything is ticking away here nicely
with 1 minute frame, message "E" in FSK/CW with speed 006, GPS
on, and < 1us pulse width. Heartbeat is beating nicely and
125MHz calibration has occurred, as have time setting and
Maidenhead locator.
I will now send a v2.03 chip (as it will be
called) to Eddie G3ZJO (proud Trimble owner) and Andy G0FTD
(UP502 GPS) and Tony G0BZB (EM406). If you three can try it
and it works on all three then I think this will be excellent
progress indeed, maybe finally the Ultimate2 GPS issues will
be over and we'll have widespread compatibility with most GPS
modules.?
Fingers crossed...
73 Hans G0UPL
?
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