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Old Feb 20, 2013, 01:18 AM
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Quote:
Originally Posted by Dennis Frie View Post
It sounds like the OSD is powered from somewhere else. When you turn it off, you say the video kinda fade? Would you mind measuring the voltage between Vcc and a ground-pad (with "faded" video)? It sounds to me like the OSD is powered anyway, but not with the required 5 volt. If a small signal/voltage is available, it might be enough to run Atmega328 but not MAX7456. That will cause Atmega328 to boot without MAX7456 running. That will give the missing overlay. If you continue to have problems just let me know, it should only be a question about a little delay to make sure MAX7456 have started properly before commands are send from Atmega328.
Vcc to Ground is 0.390 V

Connections to OSD are Gnd/Pwr/Signal from the receiver to the "PPM" connections and Vin and Vout from the camera to the VTx. I unplug the power(BEC) from the receiver and get the faded image.
I get the missing overlay with everything powered up. If I power the camera/Vtx first and then receiver/OSD it seems a better chance to get the overlay, but not always.
Would it be better to power the OSD directly with 5V from the BEC rather than through the receiver PPM plug in. My camera/Vtx are 12V. The only connection from the VTx/camera are the Vin/Vout lines.
Bill
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Old Feb 20, 2013, 02:02 AM
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Quote:
Originally Posted by Electraglide View Post
I'd Rather be safe than sorry, therefore do you have a link/tread regarding your current sensor.
I know that I never going to need 100A on my Easy Glider but on my large 4m "Epsilon XL" I just might top at 100A.

I still havent heard anything from Mehlin/Flytron yet.
Best regards
Poul
I posted it a few pages back in this thread, I should be getting some made in the next few weeks.

Not only do many of the current sensors you see for sale all use exactly the same current sense resistors, they are all underated for anything above 60amps. As a resistor, they are only rated to 2W of dissipation each. As a current shunt, 30A for the materials regardless of dissipation.

Ohmic (http://www.ohmite.com/cat/res_lvk.pdf) and Stackpole (http://www.seielect.com/catalog/SEI-CSS_CSSH.PDF) are the main current shunts which are used in the current sensors on the market. Measure your resistors size and prepare to be scared
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Old Feb 20, 2013, 04:01 AM
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It wouldn't be that difficult to add shunt resistors (adding resistors would lower voltage drop and heat dissipation) to our exisiting sensor boards and modify gain to get correct readings. Or change the OSD SW instead of HW set gain?

I guess we don't need very precise current readings, for me 5% or 10% would do just fine.

And does anybody know a low-volume or sample supplier of these resistors?
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Old Feb 20, 2013, 04:56 AM
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Denmark, Capital Region of Denmark, Naerum
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Quote:
Originally Posted by dziedrius View Post
Hm, you mean GPS configuration on start up may be optional, or does it depend on GPS module type? If it does depend on GPS module type, wondering if this would allow to leave tx pin free:
http://hobbyking.com/hobbyking/store...?strSearch=gps

On the other hand, how complicated would be to adjust pcb for additional serial communication port?
MTK-commands are send every-time the OSD boots, to ensure 5Hz update rate. But if you have a GPS configured already, you can use the serial-tx for something else.

There is only 1 UART available on Atmega328. Adding another would require software-serial or separate hardware. The Atmega328 is really quite limited and was only picked to be easy available to everyone.

Quote:
Originally Posted by SupraGo View Post
Vcc to Ground is 0.390 V

Connections to OSD are Gnd/Pwr/Signal from the receiver to the "PPM" connections and Vin and Vout from the camera to the VTx. I unplug the power(BEC) from the receiver and get the faded image.
I get the missing overlay with everything powered up. If I power the camera/Vtx first and then receiver/OSD it seems a better chance to get the overlay, but not always.
Would it be better to power the OSD directly with 5V from the BEC rather than through the receiver PPM plug in. My camera/Vtx are 12V. The only connection from the VTx/camera are the Vin/Vout lines.
Bill
No it should be fine to power the OSD through that connector, as long as you don't have 5-volt camera and video-tx connected.

My best guess is, that MAX7456 just barely gets ready before the first commands are sent from the microcontroller. By any chance I can ask you to try the following change in the code?

Find "MAX7456_OSD.ino"

On line 52-53 you should find this:
// Small delay to ensure MAX7456 is ready.
delay(100);

Try to change the delay to something like 2000. That will give 2 second delay, before the OSD starts. That should ensure, that the supply have been stabilized, MAX7456 is ready etc. 2 seconds should be way more than needed, but just to see if that's your problem.
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Old Feb 20, 2013, 05:03 AM
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Quote:
Originally Posted by mike_o View Post
It wouldn't be that difficult to add shunt resistors (adding resistors would lower voltage drop and heat dissipation) to our exisiting sensor boards and modify gain to get correct readings. Or change the OSD SW instead of HW set gain?

I guess we don't need very precise current readings, for me 5% or 10% would do just fine.

And does anybody know a low-volume or sample supplier of these resistors?
I can buy them here:
http://dk.farnell.com/ohmite/lvk25r0...002/dp/1462323

But in that case (if you need to modify the existing sensors) it's almost as easy to buy the few components needed, design a PCB and make it yourself
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Old Feb 20, 2013, 07:33 AM
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Quote:
Originally Posted by Dennis Frie View Post
Thanks!

Quote:
Originally Posted by Dennis Frie View Post
...But in that case (if you need to modify the existing sensors) it's almost as easy to buy the few components needed, design a PCB and make it yourself
I think "almost" is the operative word here. I haven't done any PCB design the last 20 years, so it would probably take me a month just to get familiar with modern SW tools

Soldering a few, simple SMD components out and in seems more manageable to me
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Old Feb 21, 2013, 01:21 AM
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Dennis,

I'm still alive! Just busy doing family things

I did get some time and updated the pcb with the new software - the numbers looked better - thank you for your help - thought I broke it

~However, I am having trouble with PPM, RSSI and Link for some reason ~ maybe I never did get it right even in the NANO version.

Do you have the EzUHF Rx or are you only working with the 4ch?

When I set the ImmersionRC beta software to the settings you posted page 33 report 484, I can not seem to get PPM with the default OSD settings?
If I set the rx to give PPM on channel 6, I can get PPM and work the menu etc. However, the RSSI and LINK numbers look weird. And it still says it is getting PPM from channel 8 ? Make sense?

Any ideas ?

Still flying Nano version on the quad ~ Hey, is the "sink rate" in feet for us USA folk, or is it in meters - my copter was coming down pretty fast the other day but the OSD sink rate looked slow

Pulled out an old "gentle Lady" glider- put a motor and gopro on it ~ was working on HD video quality, editing, and slow motion etc ~ Thinking about putting a Vtx and OSD pcb version, to get some slow FPV practice, before I put it in the screaming Zephyr !!!

Should be able to see it in 1080HD full screen !

2-16-13 Gentle Lady with GoPro (3 min 37 sec)


Now you know what winter looks like in Arizona USA

Thanks again for your help,

Rick
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Old Feb 21, 2013, 07:17 AM
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Shunt resistors

Hi guys,

I purchased a few 0.002 ohm resistors to improve the power tolerance of my 25A Flytron current sensor. I'll only use a few, so let me know, if you need one of the extras. Free against shipping cost preferably within Europe.
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Old Feb 21, 2013, 09:57 AM
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Mike,

Just for fun, next time y ou do an upgrade get double the resistance and put two resistors stacked on top of each other. This wont give you double the rating as the bottom chip will have less surface area exposed for cooling but it should give you about 70% more headroom on current
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Old Feb 21, 2013, 03:57 PM
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Quote:
Originally Posted by RickEis View Post
Dennis,

I'm still alive! Just busy doing family things

I did get some time and updated the pcb with the new software - the numbers looked better - thank you for your help - thought I broke it

~However, I am having trouble with PPM, RSSI and Link for some reason ~ maybe I never did get it right even in the NANO version.

Do you have the EzUHF Rx or are you only working with the 4ch?

When I set the ImmersionRC beta software to the settings you posted page 33 report 484, I can not seem to get PPM with the default OSD settings?
If I set the rx to give PPM on channel 6, I can get PPM and work the menu etc. However, the RSSI and LINK numbers look weird. And it still says it is getting PPM from channel 8 ? Make sense?

Any ideas ?

Still flying Nano version on the quad ~ Hey, is the "sink rate" in feet for us USA folk, or is it in meters - my copter was coming down pretty fast the other day but the OSD sink rate looked slow

Pulled out an old "gentle Lady" glider- put a motor and gopro on it ~ was working on HD video quality, editing, and slow motion etc ~ Thinking about putting a Vtx and OSD pcb version, to get some slow FPV practice, before I put it in the screaming Zephyr !!!

Should be able to see it in 1080HD full screen !

http://youtu.be/v3XKjOGBQnQ

Now you know what winter looks like in Arizona USA

Thanks again for your help,

Rick
Hi Rick
No worries, I've been quite busy as well

Year, it can happen that the characters on MAX7456 gets "messed up" when you have uploaded the software a lot of times with ISP - but you can just use character_uploader and you are good to go again.

I only have a few 4-channel EzUHF receivers and can't check with a 8-channel version. You are on your own here, but it should work just fine, if you can set it up properly in the EzUHF software. Sorry, I¨m not much help here as I cant check anything myself

Sink-rate in meters? That sounds about right
Forgot about it and never got it updated. Have a few minor details that I'll update soon, will add it to the list.

Looks good with your "gentle lady". Your landscape is quite a bit different from what we have in Denmark
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Old Feb 21, 2013, 04:01 PM
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To-do next time I update the software, anything I have missed? Feel pretty sure there was a few things more mentioned...
  • Possible to hide sink-rate and bar in config
  • Add possibility to show units instead of VLT, LOS etc
  • Update sink-rate to show feets when selected
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Old Feb 21, 2013, 04:51 PM
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Just to let you all know that I got an answer from Melih/Flytron

"Hi Poul,

Yes it is 100A current sensor.
A current sensor is a piece of wire with calibrated resistance. In this case, the resistance is 1/2000 Ohm (2x0.001 ohm). You cant burn anything with it.
Also your DIN connectors looking right connected.
If you sure about your ESC connection, I know only one reason for that. Maybe a wiring diagram problem can do that. Your current sensor output is Bat+, Current Level(0-5V) and Ground. If you connect it to wrong place, or sometimes poor grounding causes killer combination.
Do you have a wiring diagram of whole system to inspection? or a photo?"

So i guess that all the different answers I've gotten only makes me more confused, I'll seek guidens through Dennis next time we'll meet

Best regards Poul.
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Old Feb 22, 2013, 07:57 PM
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I've updated the software and changed quite a bit with the characters, to make it easier to use different layouts and modify or replace the used characters, icons etc.

All characters can just be modified on the GUI from Ascended and uploaded with the character_uploader software.

The characters are not made very beautiful, but I've just focused on the code.

Any good suggestions before I release the software?

At the moment these layouts can be selected. Off course everything can be moved around, turned on/off etc. as well - so plenty of things to change

Layout 0 (standard)


Layout 1 (Icons)


Layout 2 (units)


I will include a mix as well, but that's a job for another day
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Old Feb 22, 2013, 09:57 PM
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i like them
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Old Feb 23, 2013, 12:17 AM
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Dennis,

For some reason I thought you were going to slow down with this OSD... on the contrary, you keep on running …... tweaking things making it even better.

I think it is awesome that folks are bringing their ideas and work to you.

Its even cooler that you are able and willing to incorporate many of them.

A few questions:

You say, “Off course everything can be moved around, turned on/off etc. as well”
I have not really been focused on it ~~~
maybe you could describe for us simple folk in a read me or in the config.h file a “how to” move things around –

You say “everything” can be turned off. I' have seen many things with the “0” and “1” but are you saying “everything” can be turned off like this?

Can you make it do:

On /off for # of satelites
On/off ability for the “summary”
ability for both Pressure elevation and the gps elevation “on” at the same time
on/off for entire osd during flight
Is the artificial horizon up and running ?
can you do a few options to start the timer some how.. helpful with a quad

Not sure what some of these do ? Maybe a little more explanation for simple folks like me in the config file

- #define OSD_CONTROL_CHANNEL 5
- // Indicate channel-change from PPM
- // Show RSSI/2. battery or analog sensor

- // (can be leaved at 1, it will automatic be disabled if PPm is not detected at start-up)
- #define USE_PPM 1 ~~~~~ maybe just leave this out to simplify things – especially if it makes no difference

-Would be helpful to describe a simple method of calibrating the current sensor in the config or read me file- I still don't think I have it right
- and maybe something in the read me or config file to work with character uploader etc

Again, amazing job Dennis -

Rick
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