Serial GPS vs. I²C GPS

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jevermeister
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Serial GPS vs. I²C GPS

Post by jevermeister »

Hi,
about a year ago I tried a Serial GPS (Flyduino) on my Flyduino Mega 2560.
I noticed a massive increase on cycletime if the GPS is connected, this affected the barohold and the beeping routines due to the affected cycle times.
I want to sue the GPS for FPV flights so I can see coordinates in OSD and use Position Hold for assited flight while doing som photos without caring for keeping position. I use a lot of features and I know the controller is pretty limited but 32 bit does not support enough features for me to make the step of spending a lot of money for a new system and I like the multiwii infrastructure a lot and will miss it, since I was here from the beginning. Perhaps GPS is a thing we cannot make with Multiwii 8Bit?

My questions:
1. Has this issue been adressed until now and I can use Serial GPS now
2. Would it be wiser to switch to I²C GPS (I can easily mod my GPS wit a small arduino) (I heard I²C GPS is a dead end, is that true?)



Thanks for your infos

Nils

scrat
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Re: Serial GPS vs. I²C GPS

Post by scrat »

Gps in mwii 2.2 is working great. Forget I2c gps.

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jevermeister
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AW: Serial GPS vs. I²C GPS

Post by jevermeister »

Has ghere be a change regarding work load between 2.1 and 2.2? Maybe I used 2.0 .

scrat
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Re: Serial GPS vs. I²C GPS

Post by scrat »

Use version 2.2.

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jevermeister
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AW: Serial GPS vs. I²C GPS

Post by jevermeister »

I already use 2.2 since day one and I am pretty happy with it. I wanted to sa that I pwst used GPS on 2.0 or 2.1 so there may be improvements I missed out. :-)

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jevermeister
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AW: Serial GPS vs. I²C GPS

Post by jevermeister »

Hey, tested it in the field yesterday.Looks very promising GPS hold and home are working and beepi g is not affected. Now I need to check the baro hold together with gps hold and check the cycletime in the lab.

Cheers
Nils

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jevermeister
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Re: Serial GPS vs. I²C GPS

Post by jevermeister »

Hi,
had a nice calm day yesterday, so I tested RTH and PH.
I configued the Aux switches to set PH with Baro and Mag mode and the copter stood nailed to the sky for 5 minutes only drifting in a radius of 2m, I had time for a chat with a pedestrian and getting a soda out of the car without touching my tx. Perfect!!
Even Baro mode worked like a charme. Return Home worked perfect as usual.
I noticed a freeze of my OSD so I ahd to reset power to get it working again, maybe it was a glitch but I had the problem of freezing OSD with GPS in the past. Maybe it will be fixed with minim OSD.

Nils

ps.: cycletime testing is still due.

scrat
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Re: Serial GPS vs. I²C GPS

Post by scrat »

:)

i3dm
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Re: Serial GPS vs. I²C GPS

Post by i3dm »

jevermeister wrote:Hi,
had a nice calm day yesterday, so I tested RTH and PH.
I configued the Aux switches to set PH with Baro and Mag mode and the copter stood nailed to the sky for 5 minutes only drifting in a radius of 2m, I had time for a chat with a pedestrian and getting a soda out of the car without touching my tx. Perfect!!
Even Baro mode worked like a charme. Return Home worked perfect as usual.
I noticed a freeze of my OSD so I ahd to reset power to get it working again, maybe it was a glitch but I had the problem of freezing OSD with GPS in the past. Maybe it will be fixed with minim OSD.

Nils

ps.: cycletime testing is still due.


was that with serial GPS?
can you detail your setup?

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jevermeister
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Re: Serial GPS vs. I²C GPS

Post by jevermeister »

It was with the serial gps yes.
I heard there is conflicting with the Serial outputs if there is a sat present when pwoering everything up. This is mentioned in the RCGroups Thread too.

I have a Flyduino 2560 QuadX MultiWii 2.2 with Bluetooth on Com1, GPS on Com2 and a mobidrone OSD on Serial 3.

Need anything else?

Nils

Noctaro
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Re: Serial GPS vs. I²C GPS

Post by Noctaro »

Hey,
i had a similar problem some days ago. I took off and made my rounds, everything worked fine. Suddenly my OSD GPS data seemed to freeze. KV OSD was still working, but distance to home would not change anymore, and the direction arrow also negated to work. 8 sats present. Virtual horizont and baro data was working fine.
So you are talking about a problem with gps fix at power on? Could a reset after power on take care of it?

Could not reproduce it for now...
FFIMUv2 using MTK GPS at 57600baud in NMEA mode. INIT MTK set to active, but no firmware mod.

Greetz Noc

btw. what happens if i just remove the bat from gps module, so it should have to research sats each power on. Increases takofftime, but should work if the problem is related to this, right?

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jevermeister
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Re: Serial GPS vs. I²C GPS

Post by jevermeister »

Hi,
I adressed this issue before, but I think I posted in another thread that the osd freezes...


http://www.multiwii.com/forum/viewtopic.php?f=8&t=2866



Nils

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