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Old Aug 14, 2012, 04:50 AM
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Originally Posted by OlliW View Post
hahaha... I totally forgot about that

I have remodelled my DIY boc for another purpose, so I can't double check what I did, but, yes, you're right, the firmware should be working. However, my response to your question about the fuses was then INCORRECT, since also the fuses are different for m8 and m88(pa)... sorry for that. For the DIY box with ATmega8 I have this comment in my source file:

DIY: atmgea8
- SUT1:0= 11, CKSEL3:0= 1111, BODEN=0, BODLVL=1, Bootloader @ PD1/TXD with key, Fuses BOOTSZ1:0= 10, BOOTRST= 0
- low fuse: 0xBF, high fuse: 0xDC

I don't know whether you are using a bootloader. I guess not (since I seem not to have posted it for the DIY box), in that case the bootfuses should not be set. So, low fuse: 0xBF, high fuse: 0xD9. I don't know though whether the different fuses would affect the connectability between progbox and GA250. Maybe Hyvok can jump in and tell what he used.

If the fuses are not the issue and hardware wise everything else is double checked then you have to tell/show us a bit more about your box... I mean , the evil could sit everywhere. You're sure your ATmega8 is running at 8MHz from a crystal/ceramic? Could you describe how you tried to connect to the GA250? A (good) photo of your setup (showing the details)? I notice that in contrast to Hyvok scheme I did not use the 100Ohm resistor in the Rx/Tx line (R2 in Hyvok's scheme), not sure what this does.

I am connvinced that it is just a "little" thing which prevents correct operation, it might be just hard to find it... so, don't give up...

Olli
Yes, i got correct fuses from Hyvok, actually i flashed the uC succesfully and the box itself is working, i get the text output on lcd. The crystal IS 8MHz and the fuses look ok too.. connection to gyro is very simple, don't think i could mess something up. But i will try without 100Ohm resistor. I tried to hook up my oscilloscope to gyro and box, and i see that the gyro is giving short pulse on signal wire when power up, but the box is only listening? Is that correct?
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Old Aug 14, 2012, 06:25 AM
OlliW
Joined Sep 2009
1,429 Posts
the electrical connection is very simple, that's true... what I meant was is that the communication is not always possible at all times, i.e., it is only possible after power up (and a further trick). So, you disconnect the servo from the GA250's servo plug, you connect the progbox to the servo plug, and then power up the heli by connecting the lipo to the BESC... could you report what the leds on the GA250 are doing after power up? And what the box display is showing? (I am trying to figure out if you have some timing issues, the progbox should have "started up" before the GA250's blue led blinking finishes)

You can confirm that your fuses are SUT1:0= 11, CKSEL3:0= 1111? I had issues before with different (shorter) startup times.

The box should also respond very briefly. The communication protocoll is such that the GA250 sends one byte, then the box responds with one byte, and then the GA250 should send a couple (few ten) bytes, and this "frame" should repeat every about 15ms or so.

If all electrical connections and the hardware are correct, my guess would have been that somehow the progbox listen/talks at a different baudrate or runs at a too slow frequency.... these two reasons, a minor mistake in the progbox hardware or an incorrect clock frequency of the atmega are the two main issues I can see. The fact that the lcd and keys are working is not really telling that also the UART and/or MCU is working at the correct speed since the lcd/keys are not time critical, so from the lcds/keys one can't conclude that the box itself is really working correctly.

I am actually a bit puzzled that you have issues, and even more so since you seem to be experienced. The progbox is supposed to be a simple to build unit (usually the usb adapter is giving the head aches). Not sure what's going on here, I feel a bit of little help...
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Old Aug 14, 2012, 07:01 AM
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Quote:
Originally Posted by OlliW View Post
the electrical connection is very simple, that's true... what I meant was is that the communication is not always possible at all times, i.e., it is only possible after power up (and a further trick). So, you disconnect the servo from the GA250's servo plug, you connect the progbox to the servo plug, and then power up the heli by connecting the lipo to the BESC... could you report what the leds on the GA250 are doing after power up? And what the box display is showing? (I am trying to figure out if you have some timing issues, the progbox should have "started up" before the GA250's blue led blinking finishes)

You can confirm that your fuses are SUT1:0= 11, CKSEL3:0= 1111? I had issues before with different (shorter) startup times.

The box should also respond very briefly. The communication protocoll is such that the GA250 sends one byte, then the box responds with one byte, and then the GA250 should send a couple (few ten) bytes, and this "frame" should repeat every about 15ms or so.

If all electrical connections and the hardware are correct, my guess would have been that somehow the progbox listen/talks at a different baudrate or runs at a too slow frequency.... these two reasons, a minor mistake in the progbox hardware or an incorrect clock frequency of the atmega are the two main issues I can see. The fact that the lcd and keys are working is not really telling that also the UART and/or MCU is working at the correct speed since the lcd/keys are not time critical, so from the lcds/keys one can't conclude that the box itself is really working correctly.

I am actually a bit puzzled that you have issues, and even more so since you seem to be experienced. The progbox is supposed to be a simple to build unit (usually the usb adapter is giving the head aches). Not sure what's going on here, I feel a bit of little help...
Will double check the fuses, when i'm home, maybe i really messed up with them... And what trick you mention? I connect the gyro to box, power everything up, the gyro briefly flashes blue led and then starts flashing red, the box first display welcome message and then tells 'Device not connected' and stays this way.
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Old Aug 14, 2012, 07:32 AM
OlliW
Joined Sep 2009
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Quote:
the gyro briefly flashes blue led and then starts flashing red, the box first display welcome message
the welcome message on the box should last shorter than the gyro is flashing the blue led. I.e., the box should have finished with start up. welcoming etc, BEFORE the blue flashing ends and the gyro goes ahead with red flashing.
Quote:
And what trick you mention?
I found it inconvennient to always having to disconnect/connect the lipo, so it's possible to connect to the progbox by pluging it into the servo plug and hold the rudder stick for 10 secs to the left (the heli has to stand still)... this will make the gyro firmware to kind of restart and hence pass again the "try-to-connect-to-the-progbox-and-blink-blue-led" phase...
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Old Aug 14, 2012, 10:07 AM
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Quote:
Originally Posted by OlliW View Post
the welcome message on the box should last shorter than the gyro is flashing the blue led. I.e., the box should have finished with start up. welcoming etc, BEFORE the blue flashing ends and the gyro goes ahead with red flashing.
I found it inconvennient to always having to disconnect/connect the lipo, so it's possible to connect to the progbox by pluging it into the servo plug and hold the rudder stick for 10 secs to the left (the heli has to stand still)... this will make the gyro firmware to kind of restart and hence pass again the "try-to-connect-to-the-progbox-and-blink-blue-led" phase...
Now, i feel like stupid idiot
I used the red connector bootloader and i was sure i have to use red connector to connect prog box too. Tried the servo connector and all is working now, thanks
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Old Aug 14, 2012, 10:48 AM
OlliW
Joined Sep 2009
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No problem, I am glad your issue could be resolved that easily!
Have fun with flying. It would be nice if eventually you could report back your experiences
Cheers, Olli
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Old Aug 22, 2012, 01:44 PM
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Czech Republic, Olomouc
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Hi Olli,
could you please describe how RUDD RATE exactly works?
I use iit on fixed plane and have 3pcs GA250 with RR 1.0 1.5 and 2.0 on rudder elevator and aillerons.
I wonder if RR multiplies inputs and trims to some limits or multiplies and use it in PID equation directly (with no limits trims)?
For example in TX I use 100% EPA x RR 2.0 = 200% Will I got 200% of gyro rate?
Thanks
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Old Sep 04, 2012, 08:22 AM
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Please ignore this post.
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Last edited by Steve Joblin; Sep 04, 2012 at 01:59 PM.
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Old Sep 04, 2012, 03:10 PM
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Originally Posted by OlliW View Post
No problem, I am glad your issue could be resolved that easily!
Have fun with flying. It would be nice if eventually you could report back your experiences
Cheers, Olli
Well, at last i got my heli together and weather was not terrible, so i had a chance to try gyro. I did not change any settings from default, so i got heavy back bouncing when turning counterclockwise but sharp nice stops clockwise. But wind was so strong, that i decided not to tweak the settings and wait for better weather. But at least it works and holds tail in strong crosswind
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Old Sep 09, 2012, 09:54 AM
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Hi OlliWe

Great Work

Is it possible to convert code for DIY program box for BLheliBox (Atmega328)

Thanks Nick
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Old Sep 10, 2012, 08:17 AM
OlliW
Joined Sep 2009
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@ablack:
it just multiplies to the incoming rudd signal...

if the incoming rudd signal is e.g. 1639 us, it is centered by subtracting the signal for rudd midd (let's assume it to be 1507 us) and then multiplied by Rudd Rate (let's assume 1.1), so the rudd signal used by the gyro is then

1.1 * ( 1639 us - 1507 us ) = 145 us

@andrejsstumpf:
COOL
keep us posted how it goes further

@nikosd:
not sure I understand your question

if you are asking if it's possible to use the hardware, which you are using as progamming box for the modded GA250 (e.g. the Robe box or one of the various DIY boxes presented in the above) to operate as BLHeliBox, then the answer is: maybe. If it uses an ATmega8 or ATmgea88 then its no, if the mcu is ATmega168 or ATMega328p, then yes but with some (minor) hardware modifications

if you are asking if it's possible to use the hardware, which you are using as BLHeliBox, to operate as programming box for the modded GA250, then the answer is: most likely. If its a Arduino Uno + LCD shield, it can be directly used as GA250 programming box (I have the code somewhere, but think I have never posted it anywhere)


Cheers, Olli
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Old Sep 11, 2012, 12:31 AM
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Good Morning OlliW

The second option

{ If its a Arduino Uno + LCD shield, it can be directly used as GA250 programming box }

Please if you have a code send us a link to download.

Have a good day Nikosd
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Old Sep 13, 2012, 01:02 AM
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Quote:
Originally Posted by OlliW View Post
@andrejsstumpf:
COOL
keep us posted how it goes further
Well, yesterday i had a chance to fly heli and tune the gyro. What can i say? It works really great At least from my unprofessional point of view. And sure i can recommend this mod to all heli flyers.
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Old Oct 17, 2012, 09:32 AM
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Hi olliw,
I just programmed my hk450 gyro. However, each time that connect the battery, for a few instants, the servo reaches its end position, going to force the command on the tail beyond the limits. I'm afraid that in the long run can lead to the failure of the servo.
The servo is a MKS480, firmware is 0.16
I made a video to show my problem.

Assan GA250 gyro with olliw firmware 0.16 startup issue (0 min 15 sec)


Thank you for this fantastic project
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Old Oct 17, 2012, 10:15 AM
OlliW
Joined Sep 2009
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Hey Sparkie,

there is nothing obvious which comes to my mind here... unfortunately... so, we need a bit patience and have to do a bit of research (but I am sure we get this sorted out, so far it always got sorted out :-))

Maybe at first some little checks.

- The MKS480 can handle only 5.0V at most (it is IMHO also a bit "small" for a 450, but that's another cup of tea). I assume that you have checked that your BESC is not delivering more than 5.0V, and that the servo is working properly when e.g. attached directly to the reciever?

- According to the sepcs I found on the web the servo can handle 1520us at 333Hz. This should be perfect. Nevertheless, just as a quick double check, what would happen if you would set the gyro output to 70 Hz?

- You are sure you have connected the gyro correctly to the reciever? And that the reciever is set up properly (in particular failsafe settings can be a pain)

- You are sure that burning the bootloader and flashing the firmware was really successful? (maybe you could post a screenshot of the output tab of AVRootloader)

I know, most likely all this is perfectly OK, but things happen, you know, and I am just trying to sort out things... Ok, let's assume now a problem with the gyro. Unfortunately, as said, at the moment I can't be of much help, I'd like to ask for some more info:

- The GA250 has two Leds, a blue and a red one. What are the leds doing after you power up the gyro/heli? Try to look carefully and to report carefully what they are doing, the leds behavior can be a tremendously useful diagnosis tool. Repeat also with the gain switch at the transmitter set to heading hold and to rate mode. (in one of the first posts you find a description of what the leds are supposed to do, as well as in the pdf manual).

- Could you also post a screen shot of AvrConfig with the settings of your GA250? This too can be a most helpful info

- What transmitter and reciever are you using?

Cheers,
Olli
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