Posts: 20 Threads: 5 Likes Received: 0 in 0 posts Likes Given: 0 Joined: Jun 2018 Reputation: 0 24-Mar-2019, 09:32 PM (This post was last modified: 24-Mar-2019, 10:39 PM by savinovalex.) Ok, I made a mistake regarding X8R receiver. I thought I can test quad as-is and fastened X8R weakly. It got under a prop and was damaged.  At least, I should remove this huge plastic cover someday, isn't it? Ok, I've attached antennas back (they are easy to be glued later), straightened pins, resoldered SBUS pins to make sure and current state is: 1. Receiver's LED is green, and I have telemetry on X9D from the receiver 2. "No valid receiver signal" Betaflight says 3. I've tested continuity of each 3 wire between F4 board pins and X8R SBUS pins - ok 4. There is NO ANY mark of props have touched inners of the receiver, I've looked very thoroughly and there is no visual damage at all 5. There are 1.4-1.6 volts between black and yellow SBUS pins on flight controller board, so looks like some signal is presented? Please help me investigate issue since I don't have any spare parts. Flight controller has been damaged or X8R receiver? I didn't see any strange things in Betaflight configurator, f.e. accelerometer works fine. Maybe I missed something? How do I know if I can switch quickly controls to FrSky smart port? How can I make sure it's problem of X8R for sure? Thank you in advance. ![[-]](https://intofpv.com/images/collapse.png) • Posts: 12,098 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 Sounds like you were using PWM. Bend the pins back and reconnect everything. You can check the receiver tab in BFC to see if you are getting any signal. If you do not get any signal, then you can test the receiver. Use an oscilloscope to see if you getting any PWM signal. You can also wire an LED to ground and signal. It should light up brighter when you increase the PWM.
If you confirm that receiver works, then maybe something is wrong with your FC.
Let start there. • Posts: 20 Threads: 5 Likes Received: 0 in 0 posts Likes Given: 0 Joined: Jun 2018 Reputation: 0 Voodoo614, I'm using SBUS so it's a serial method of data transfer, right? Switching to PWM looks like not very fast movement. Can we test SBUS or switch to Smart Port (if it sends controlling signals) quickly? • Posts: 12,098 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 SBUS is hard to test. I believe it is too fast for most oscilloscope. S. Port is for telemetry. It will not give you controls.
F. Port would be an option, but X8R doesn't have F. Port firmware, so you are out of luck.
Let me think about it for a bit. • Posts: 21,416 Threads: 595 Likes Received: 9,039 in 6,690 posts Likes Given: 1,428 Joined: Jun 2018 Reputation: 796 You can test SBUS output using an ISDT BG-8S battery tester. I've got one but I've never used it to test a receiver output with. However, there are plenty of videos on YouTube showing how to use that feature.
I guess it depends if you already have an ISDT BG-8S, or if you're prepared to invest in one to try and test your X8R to find out if it's that or the FC at fault. • Posts: 12,098 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 I can really think of how to rule out problem without spare parts. • Posts: 21,416 Threads: 595 Likes Received: 9,039 in 6,690 posts Likes Given: 1,428 Joined: Jun 2018 Reputation: 796 (24-Mar-2019, 11:02 PM)SnowLeopardFPV Wrote: You can test SBUS output using an ISDT BG-8S battery tester. I've got one but I've never used it to test a receiver output with. However, there are plenty of videos on YouTube showing how to use that feature.
I guess it depends if you already have an ISDT BG-8S, or if you're prepared to invest in one to try and test your X8R to find out if it's that or the FC at fault. Here you go. Lee has a really good demonstration on how to test a receiver using the ISDT BG-8S. Just fast forward to 3:48 in the video below to see it in action... • Posts: 20 Threads: 5 Likes Received: 0 in 0 posts Likes Given: 0 Joined: Jun 2018 Reputation: 0 Guys, I don't have ISDT BG-8S, but looks like this https://oscarliang.com/diy-sbus-usb-converter/ is the fastest way. There are STM32F103C8T6 in my town's shops. What do you think? • Posts: 21,416 Threads: 595 Likes Received: 9,039 in 6,690 posts Likes Given: 1,428 Joined: Jun 2018 Reputation: 796 (25-Mar-2019, 06:17 AM)savinovalex Wrote: Guys, I don't have ISDT BG-8S, but looks like this https://oscarliang.com/diy-sbus-usb-converter/ is the fastest way. There are STM32F103C8T6 in my town's shops. What do you think? Yes, I guess that's an option. I read through the article and thought to myself that it seemed a lot of work just to test the SBUS outputs, but then I read the first comment by Ched999uk right at the bottom of the article which I've quoted below:- Ched999uk Wrote:There is a much easier way to do this for FRsky and FlySky rx. Basically just connect the rx to an FTDI set to 5V for power and the rx signal pin to the rx pin on FTDI. then use a piece of free software called VJoy!
vjoystick.sourceforge.net/site/index.php/download-a-install/download
and the plugin
github.com/Cleric-K/vJoySerialFeeder/releases
Then run the software and set to SBus or iBus and add axis and buttons as necessary, calibrate and away you go.
You just run the VJoy software then start your sim.
So no soldering to do and no extra STM32F1 Development Board or resistors and soldering… So it looks like if you get yourself an FTDI adapter you can just use that along with the vjoystick software mentioned. You should then still be able to test the channel outputs in Windows using the same method in Oscar's article under the "Check If It Works" heading although the joystick device will likely have a different name than "Maple". Take note that the first link appears to be broken so just go the vjoystick the home page instead: https://sourceforge.net/projects/vjoystick • Posts: 20 Threads: 5 Likes Received: 0 in 0 posts Likes Given: 0 Joined: Jun 2018 Reputation: 0 SnowLeopardFPV, wow, I was inattentive. Thank you very much for finding this comment! I'll test receiver in nearest time. Don't know I wish it to be broken or not, lol. • Posts: 20 Threads: 5 Likes Received: 0 in 0 posts Likes Given: 0 Joined: Jun 2018 Reputation: 0 29-Mar-2019, 08:44 PM (This post was last modified: 29-Mar-2019, 10:20 PM by savinovalex.) Guys, looks like X8R is dead. I was able to get signal from smart port with Device Monitoring Studio. On baud rate 56000 it keeps saying "7%" line-by-line. I also flashed receiver firmware. Interesting sign is: there is ~0.80 volts on Smart Port signal pin, and USB-TTL converter lighting with blue LED. When the transmitter is off the SBUS signal PIN has the same 0.8 volts and USB-TTL lights blue. No messages came, but I think it's correct. When transmitter is ON - telemetry OK - there are 1.5-3.5 volts on signal PIN, USB-TTL blue is off and still not signal. Looks like there is some parasite connection inside receiver between radio receiver circuit and SBUS circuit. Strange, still don't see anything been damaged.
Which FrSKY receiver for X9D+ I should buy instead? Maybe go to the CROSSFIRE from the start?
UDP. Have read Oscar's article, I'm going with R9M. • Posts: 3,288 Threads: 129 Likes Received: 2,740 in 1,644 posts Likes Given: 2,969 Joined: Apr 2017 Reputation: 65 There are a few of us that use the R9M. I have had mixed luck with mine, though it was on an old firmware. It is since updated and have not had a chance to test it. I have had it out to a few kilometers without issue and at the same time, I have had it failsafe inside of 500 meters, though this was at 10mw.
Anyway, if you choose to go with the R9 system, we are here to help with any issues we have experienced so far! SoCal Kaity :D
OMG, no one told me it would be this much fun! Addicted :) • Posts: 20 Threads: 5 Likes Received: 0 in 0 posts Likes Given: 0 Joined: Jun 2018 Reputation: 0 (30-Mar-2019, 01:17 AM)kaitylynn Wrote: There are a few of us that use the R9M. I have had mixed luck with mine, though it was on an old firmware. It is since updated and have not had a chance to test it. I have had it out to a few kilometers without issue and at the same time, I have had it failsafe inside of 500 meters, though this was at 10mw.
Anyway, if you choose to go with the R9 system, we are here to help with any issues we have experienced so far! Hi! Sooo I need some assistance now. I've bought R9M + R9M Slim and I'm installing it now: 1. I've connected it to the flight controller with kind of long circuit (didn't want to damage a wire) and it becomes like a 40 cm aluminum wire and the receiver hasn't enough power for telemetry! So it requires 100mA@5V, and want I'm thinking about is maybe I should power it up from PDB directly? Or there is no such constraint? I'll test short wires from FC later, now just thinking how to do it in the "right" way. 2. Should I fear power engine wires? How much interference is for 900 MHz signals? • Posts: 3,288 Threads: 129 Likes Received: 2,740 in 1,644 posts Likes Given: 2,969 Joined: Apr 2017 Reputation: 65 (02-Apr-2019, 09:03 AM)savinovalex Wrote: Hi! Sooo I need some assistance now. I've bought R9M + R9M Slim and I'm installing it now:
1. I've connected it to the flight controller with kind of long circuit (didn't want to damage a wire) and it becomes like a 40 cm aluminum wire and the receiver hasn't enough power for telemetry! So it requires 100mA@5V, and want I'm thinking about is maybe I should power it up from PDB directly? Or there is no such constraint? I'll test short wires from FC later, now just thinking how to do it in the "right" way.
2. Should I fear power engine wires? How much interference is for 900 MHz signals? Provided the power supplied is between 3.5 and 10 volts DC, you can power it from the PDB. I have the Slim+ installed on my 7" and the power is pulled from the dedicated 5vdc that is for the camera. Those pads were available as I power the camera through the VTX. No issues at all. I would trim the wires down so that there is less a chance that they will migrate into the props. SoCal Kaity :D
OMG, no one told me it would be this much fun! Addicted :) Posts: 21,416 Threads: 595 Likes Received: 9,039 in 6,690 posts Likes Given: 1,428 Joined: Jun 2018 Reputation: 796 (02-Apr-2019, 01:24 PM)kaitylynn Wrote: I would trim the wires down so that there is less a chance that they will migrate into the props. Yes, and not just that but the shorter the wires the less electrical noise there will be on them. |
