Hi everybody. As said elsewhere, I'm new to DIYdrones and I hope I type my inputs at right places.I'm currently in final stages of building my personal FPV/UAV platform (2m trainer Kadet Senior, outrunner driven).If I am quite convinced by adding ArduPilot + FMA coPilot + 5Hz GPS for navigation, I still wonder what OSD would be most useful for my budget. When a looked at specs of the Inspire OSD, two questions came to my mind:1) is there a way for both boards to share a single 5Hz GPS chip or is the ArduPilot able to communicate its position to the OSD (latter would be my preferred solution)2) since the Inspire OSD is able to exploit waypoint routing from a Garmin Geko handheld GPS, would there be a chance for this OSD to read and display the current waypoint target from ArduPilot during navigation.If anybody has experience with one or both boards, I would be glad to know. Thanks.
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A week ago or so, I inquired if serial Out of ArduPilot is at TTL level (or regular RS-232 level).
Since nobody answered, I suspect it is a too basic question to ask and I suspect the answer is TTL.
Unfortunately, I cannot check it out on the board itself, since it is still traveling! But in the meantime, I could prepare eventual RS232-TTL conversion if needed (though I hope not).
Thanks if someone could confirm what I suspect.
I have a question concerning the serial OUT of ArduPilot. Is it a "real" serial level or a TTL signal.
I ask because to feed the Inspire OSD serial in I need RS-232 level. So if ArduPilot serial OUT is TTL, I need to convert signal level (DIY converter with MAX232 IC from Maxim and 4 x 100nF (0.1uF) capacitors as described here.
I noticed this when I tried to connect RS-232 serial of Inspire OSD to my FTDI TTL breakout... (FTDI survived).
If anybody has any information about ArduPilot serial OUT levels, I'll be glad to get them. Thanks.
I asked people at DPCAV, distributing the Inspire OSD, if they know of anybody who might have implemented both ArduPilot and Inspire OSD. Unfortunately, the answer is negative. But on the other hand, Mr Thomas Black of DPCAV gave me infos regarding the communication protocol used by the Inspire OSD in its relation to Garmin handheld GPS which can be coupled: "The Inspire OSD uses the Garmin $GPRMB sentence for determining the waypoint data to display. So, I suppose you could create a solution if you adapted the ArduPilot code to provide the $GPRMB, $GPGGA, and $GPRMC NMEA data to emulate the Garmin handheld GPS."
He transmitted following details to $GPRMB (waypoint sentence):
$GPRMB,A,0.66,L,003,004,4917.24,N,12309.57,W,001.3,052.5,000.5,V*20
where:
RMB Recommended minimum navigation information
A Data status A = OK, V = Void (warning)
0.66,L Cross-track error (nautical miles, 9.99 max),
steer Left to correct (or R = right)
003 Origin waypoint ID
004 Destination waypoint ID
4917.24,N Destination waypoint latitude 49 deg. 17.24 min. N
12309.57,W Destination waypoint longitude 123 deg. 09.57 min. W
001.3 Range to destination, nautical miles (999.9 max)
052.5 True bearing to destination
000.5 Velocity towards destination, knots
V Arrival alarm A = arrived, V = not arrived
*20 checksum
For ArduPilot to work with Inspire OSD, a change in ArduPilot is thus necessary to emulate such Garmin sentences.
Replies
Since nobody answered, I suspect it is a too basic question to ask and I suspect the answer is TTL.
Unfortunately, I cannot check it out on the board itself, since it is still traveling! But in the meantime, I could prepare eventual RS232-TTL conversion if needed (though I hope not).
Thanks if someone could confirm what I suspect.
I ask because to feed the Inspire OSD serial in I need RS-232 level. So if ArduPilot serial OUT is TTL, I need to convert signal level (DIY converter with MAX232 IC from Maxim and 4 x 100nF (0.1uF) capacitors as described here.
I noticed this when I tried to connect RS-232 serial of Inspire OSD to my FTDI TTL breakout... (FTDI survived).
If anybody has any information about ArduPilot serial OUT levels, I'll be glad to get them. Thanks.
He transmitted following details to $GPRMB (waypoint sentence):
$GPRMB,A,0.66,L,003,004,4917.24,N,12309.57,W,001.3,052.5,000.5,V*20
where:
RMB Recommended minimum navigation information
A Data status A = OK, V = Void (warning)
0.66,L Cross-track error (nautical miles, 9.99 max),
steer Left to correct (or R = right)
003 Origin waypoint ID
004 Destination waypoint ID
4917.24,N Destination waypoint latitude 49 deg. 17.24 min. N
12309.57,W Destination waypoint longitude 123 deg. 09.57 min. W
001.3 Range to destination, nautical miles (999.9 max)
052.5 True bearing to destination
000.5 Velocity towards destination, knots
V Arrival alarm A = arrived, V = not arrived
*20 checksum
For ArduPilot to work with Inspire OSD, a change in ArduPilot is thus necessary to emulate such Garmin sentences.
2) Probably not. The serial port is being used to communicate with the GPS.