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Mr.RC-Cam

Inspire OSD System with GPS Telemetry

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The long awaited Inspire OSD system is now available. For those that have been wondering about cost, prices are now posted (slightly discounted for now). The User Guide is available too.

Official Web site is here: Inspire Web Page

If you have questions about the Inspire OSD board then this is a good place to post them. At least for now.

post-3-1147824804_thumb.jpg

Edited by Mr.RC-Cam

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Wow, nice!

I love waypoint routing feature. Can you make it work with your own GPS (to save weight) and only point toward coordinates that were stored when GPS was powered up?

What is the total weight?

What is update frequency of your GPS module?

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Can you make it work with your own GPS (to save weight) and only point toward coordinates that were stored when GPS was powered up?

I've been thinking about that. Frankly, I tried to solve the various demands for the waypoint routing feature by using the Garmin Geko. It has a nice user interface and the weight can be dramatically reduced if the plastic case and batteries are eliminated. And it will allow route following and waypoint homing.

What is the total weight?

The OSD's weight is 3 oz. The micro-GPS is another 0.5 oz. If the OSD's covers were removed, I think the weight would go down to about 2.2 oz + GPS. BTW, the stock Geko 201 GPS is 3.3 oz with batteries. I think that could be cut in half by gutting the case and batteries. Perhaps more if someone was really determined. :)

What is update frequency of your GPS module?

The micro-GPS is 1-Sec update (1Hz). The Geko 201 is 2-Sec update (0.5Hz).

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Thanks.

I presume there is a way to modify the amount of information on the screen. For example if I don't need lat long coordinates, can I remove them? But then I'd like to keep bearing angle on the bottom line of the screen (and not on the third from the bottom as shown in the example), is it possible?

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I presume there is a way to modify the amount of information on the screen. For example if I don't need lat long coordinates, can I remove them?
Sure can. It's a simple procedure to enable or disable any data field.

But then I'd like to keep bearing angle on the bottom line of the screen (and not on the third from the bottom as shown in the example), is it possible?
Relocating the fields is not available in the configuration menus. If you have something special you need then maybe I can help with it after the dust settles. But it would be grand if you can work with the stock field positions.

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But then I'd like to keep bearing angle on the bottom line of the screen (and not on the third from the bottom as shown in the example), is it possible?

I received a couple of strong objections to the existing heading data field location. So, it will be moved to the upper right (below the alt/speed fields). Is this new location better for what you had in mind?

Details to the rc-groups discussion (sparked by a video file posting) is found here: http://www.rcgroups.com/forums/showthread.php?t=521098. There is a screenshot at post #24 that shows the new format.

It's open to discussion: If the location change makes things worse then please let me know.

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I find that the lower to middle section of the screen is very important for visual perception. I'd try to keep it as uncluttered as possible, and have an option of removing all the lines in the lower half of the screen (except may be one at the very bottom) in case somebody wants to fly from camera view not just use it to frame the shot. Upper right for heading angle sounds as a better spot to me.

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Upper right for heading angle sounds as a better spot to me.

Done. That is where it will go.

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Agreed - seeing the ground is more important than the sky :P

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The software change has been made: heading is now near the top of the screen (s/w release V3.3). Keep in mind that any unwanted field can be turned off. And, a R/C channel can be used to remotely turn off the entire OSD overlay when a totally clear view is desired. Screenshot shown below:

post-3-1148507131_thumb.jpg

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If I may make a suggestion, move the GPS coordinates up to the top, and move the timer and glitch counter (I believe that's what the G:0 is) to the bottom. That way all of the navigation information is contained in the top of the screen, and all other misc. information is at the bottom.

BTW, what is the "R:23"?

Brian

Edited by twinturbostang

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G:0 is the glitch count. R:23 is the photo/event Record count.

The Lat/Lon are probably the first fields to be turned off by a user. So, by leaving them on the bottom of the screen, turning them off will free up the ground view. So it would probably be best to leave them there.

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I love waypoint routing feature. Can you make it work with your own GPS (to save weight) and only point toward coordinates that were stored when GPS was powered up?

This should interest you: There is a GPS waypoint engine project going on at the rc-groups site. The author (MX) sometimes visits this site and he is certainly encouraged to start up a new thread on this site too.

As luck would have it, he is using the same GPS module that Inspire uses. For basic return home functionality, it memorizes the home waypoint on boot up. It will be able to store a route too. Best of all, it is open source and he will offer a populated PC board to help out.

Just what the doctor ordered!

Full details: http://www.rcgroups.com/forums/showthread.php?t=515929

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There is a GPS waypoint engine project going on at the rc-groups site.

Thanks, I'll check it out.

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Can I plug a Garmin GPS18 into the EM-406 port? It uses the same connector. Only two pins need to be swapped to match the pinouts of the Inspire.

Edited by docphi

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I don't have any experience with the Garmin GPS18. If the serial interface is TTL non-inverting then that is a good start as far as the Micro GPS's input connector goes. If it has standard RS-232 voltages on it then it may damage that interface, so Inspire's special RS-232 port would need to be used. Beyond that, the NMEA sentences will need to be friendly. Even though the NMEA GPS sentences observe "a standard," sadly they are not all alike.

It would be great to hear it works. So, please let me know if you need any other assistance to help along with the experimentation.

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I think what I should have asked is if the Inspire micro GPS input port is compatible with other micro GPS units besides the EM-406. As always, you have read my mind and provided a very helpful response. I'll let you know how my experiment goes...

"The unit accepts TIA-232-F (RS-232) level inputs and transmits voltage levels that swing from ground to the positive supply voltage, TIA-232-F (RS-232) polarity."

Edited by docphi

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I should have asked is if the Inspire micro GPS input port is compatible with other micro GPS units besides the EM-406.

Electrically, it should be compatible with other GPS "modules." These OEM components offer TTL (3V or 5V) non-inverted logic levels that can be accommodated by the special micro-GPS connector found on the Inspire OSD. However, the typical consumer handheld GPS unit is designed to plug into a PC, so it would use a more traditional RS-232 or USB serial interface. Fortunately, Inspire's RS-232 input is designed to accept handheld GPS systems that utilize a traditional serial interface.

"The unit accepts TIA-232-F (RS-232) level inputs and transmits voltage levels that swing from ground to the positive supply voltage, TIA-232-F (RS-232) polarity."

I think that you will find the TIA-232-F's 5V logic level signal to be inverted (so that it can interface with a PC's RS-232 port). So, I don't think it will work.

Another way to put this is that if the GPS18 works when connected directly to a PC's RS-232 port, then it will not work when connected to Inspire's micro GPS connector. Even if the voltage levels are the same, the logic will be inverted. However, if you wish to use the micro-GPS connector then there are ways to accommodate this (an NPN transistor can be utilized to invert such signals).

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Yup, logic signal is inverted. Works great on the Inspire's RS-232 input. However, as predicted, the signal needs to be inverted on the micro GPS port. Great learning experience! I love this stuff! :D

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Glad to hear you got it working.

Does the GPS18 have a waypoint engine in it (not to be confused with PC based waypoint support)? If it does, do you see correct waypoint information in Inspire's special waypoint data fields?

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It uses $GPGGA, $GPRMB, and $GPRMC. When the EM-406 microGPS module is used, the unneeded sentences are automatically turned off for you.

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Thomas,

Is there a possibility of upgrading the baud rate on the RS-232 port? Perhaps something faster than the 19200 max right now?

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I can create a special Inspire release that includes 28.8K and 38.4K bauds for you to try on your EB-85A GPS module. Do you have the optional Inspire cable that is used for re-flashing?

Please keep in mind that there is the chance it won't work. Those fast serial bit rates leave very little time for the application code to run. In that regard, it would be very helpful if you disabled ALL NMEA sentences except $GPGGA, $GPRMB, and $GPRMC. If you use the servo (AUX) camera control feature, the servo will probably have lots of jitter with the high bauds.

Finally, does the EB-85A work with inspire at 4800 baud? How about 19.2K?

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