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Re: Taranis QX7 bluetooth
Posted: Sun Sep 16, 2018 1:05 pm
by jhsa
I have a few P Channel Mosfets which are logic level. Will try them when I have some time.. The problem is most of what I have are.SMD
Thanks
João
Re: Taranis QX7 bluetooth
Posted: Sun Sep 16, 2018 9:46 pm
by MikeB
This is a version using a MOSFET to switch the power:
- BTpower1.png (4.25 KiB) Viewed 25611 times
I had this built (without the capacitor) on a piece of stripboard using surface mount devices so I tried it.
The capacitor could be a lower value than 1uF, I think 0.2uF would be OK. As shown, the circuit holds the power on for over 200mS after the TxD signal goes low, 40mS would be fine.
I'm running from 3.3V and using a 120 ohm resistor as the load, so around 27mS, which is, I think about the current needed by a HC-05.
Mike
Re: Taranis QX7 bluetooth
Posted: Mon Sep 17, 2018 6:33 am
by jhsa
Thanks Mike, I see you omitted the resistor going from the base of the BJT to ground on your first schematic. Won't that prevent the transistor to turn OFF? Or is it enough when you pull the processor pin low?
Also is the pin floating at any occasion, for example, at power ON? That could activate the power to the Bluetooth, right? Or am I completely wrong here.
I am asking because I had trouble when buding my safe power switch for the 9x radios. The radio didn't want to turn OFF without the resistor between the base.of the transistor and ground. he circuit is very.similar to yours. My circuit prevent the radio and RF module from turning OFF if any part of the power switch fails. You might remember that it happened to my 9XR-PRO.
João
Re: Taranis QX7 bluetooth
Posted: Mon Sep 17, 2018 6:45 am
by Kilrah
A FET is controlled by voltage, so leaving the pin floating is bad since any stray signal can turn it on. A BJT is controlled by current, so won't turn on unless something actively pushes current through it.
Re: Taranis QX7 bluetooth
Posted: Mon Sep 17, 2018 8:18 am
by MikeB
In addition, the TxD signal, in operation, is driven both high and low so the resistor in the signal path doubles up as pulling the base low.
In the second circuit, I had it already built so the resistor to ground was already present.
Mike
Re: Taranis QX7 bluetooth
Posted: Mon Sep 17, 2018 12:30 pm
by jhsa
Kilrah wrote: ↑Mon Sep 17, 2018 6:45 am
A BJT is controlled by current, so won't turn on unless something actively pushes current through it.
Well, as I said above, I have seen the opposite. The circuit wouldn't turn off if I didn't connect a resistor between base and ground.
Looking at the circuit Mike posted (without the resistor), that is why I also said that it might not be necessary as the processor pulls it low. But then I thought that the pin might be floating at power ON for example..
João
Re: Taranis QX7 bluetooth
Posted: Mon Sep 17, 2018 3:17 pm
by jhsa
Mike, Through hole N channel Mosfets are more readily available than P channel. this would allow people to build the circuit on a bit of stripboard. Could something like in the picture be used? I tested the circuit in a circuit testing software and it seems to work.
Although the BS170 datsheet states that its maximum current is 500mA, I am not sure it would be enough for the BT module?? Must try it
João
EDIT: Hmmm, the BS170 Vgs might not be low enough at 200mA.. It would be good if powering the module with 5V, I think. Need to test this
EDIT_1: I have just checked the HC-05 datasheet, and apparently only takes around 35mA. I think that makes the famous BS170 suitable for the job.
According to the datasheet, the graphic shows that for a current of about 150mA the Vgs has to be around 3.3V for the Mosfet to be fully ON. Please check attached picture. That should be ok for the HC-05??
Re: Taranis QX7 bluetooth
Posted: Tue Sep 18, 2018 11:30 pm
by MikeB
You are switching the ground rather than the power. With the positive supply still connected, I think it likely that driving the TxD signal low will cause the protection diodes on the TxD input to conduct and try to power the BT module.
I think we need to switch the power not the ground.
Even though I used surface mount devices, I have the second circuit built on stripboard. I'll see if I can post a picture of it tomorrow.
I have some firmware changes in place for the SKY, AR9X, 9XR-PRO, 9Xtreme and QX7 that drive the TxD signal low if the BT module function is set to OFF. There is a new function "Telem", if you want to enable the BT module for sending telemetry out rather than any of the other functions. While this new option appears immediately after "OFF", the internal codes used for the BT function are unchanged. Currently, you will need to also set the "BT Telemetry" option to "ON", although I think that will become unnecessary.
While not obvious, the BT function setting is a model setting not a general setting, so the BT module enable may change as you change models.
These changes will be in the next test version (R222c2), and I may get that posted tomorrow. I'd like to test the above power switch circuit with the firmware changes before I post them.
Mike
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 6:10 am
by jhsa
Thanks Mike, I have been quite busy lately, but I have a radio with skyboard open on my computer desk, so I think I could test on that one.. Did you find a through hole low Vgs P channel Mosfet? Or did I misunderstand your post as usual?
I do have a few logic level P channel Mosfets, but they are all SMD power Mosfets. I can live with it, but I was thinking about the people that can only handle through hole components, as they don't need a real PCB, and are easy to solder.
João
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 11:58 am
by MikeB
This is my stripboard (without the capacitor), but it is all surface mount.
- BTpower.JPG (24.89 KiB) Viewed 25619 times
I've just tested this on an AR9X board and a HC-06. It all worked fine, setting the BT Function to off, turned the power to the module off, setting the BT Function to something else and it powered on and functioned correctly. I ran BT trainer between this and my SKY board radio that has a HC-05 in it.
I changed the 1uF capacitor to a 0.2uF capacitor (two 0.1uF in parallel) and with the BT trainer running at 115200 baud, the capacitor only discharged by 0.2V at most.
Mike
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 12:52 pm
by jhsa
Thanks Mike, what MOSFET is that one? Can't really understand the markings
João
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 3:49 pm
by MikeB
I just updated the resistor and capacitor values on the circuit I posted above. The two transistors are as shown on that circuit, BC817 for Q3 and SI2301 for the MOSFET.
Mike
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 4:21 pm
by jhsa
Thanks Mike..
I think I found a suitable Mosfet in my components box
AO3401, which was used on the first Ar9x board (I think), and then replaced with the AO3407A. Both are identical, but the 07A has a higher maximum Vgs, 20V against 12V from the AO3401. The 3401 has a lower Gate threshold voltage, so perhaps more suitable for our application. Please see the attached picture. I believe it is low enough for the 3.3V supply. What do you think?
Thanks
João
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 4:49 pm
by MikeB
That looks OK.
I've just posted a new test version of ersky9x that sets the TxD signal low if the BT Function is set to off.
Mike
Re: Taranis QX7 bluetooth
Posted: Wed Sep 19, 2018 11:23 pm
by jhsa
Thanks Mike.. Will try to test it on Friday. Too busy with work tomorrow.. Not complaining though
João
Re: Taranis QX7 bluetooth
Posted: Mon Oct 15, 2018 1:56 pm
by abdulfpv
MikeB wrote: ↑Sat Jan 20, 2018 10:21 pm
I think this is working, although it needs a bit more testing. I'll post updated firmware on the test versions thread in a few minutes.
This is where to wire the HC-05 to the QX7 main board:
Qx7BT.jpg
You will need to modify the HC-05 as shown here:
http://openrcforums.com/forum/viewtopic.php?f=7&t=7640, in order for the control signal to work.
There will probably need to be a few minor changes, you may find that you need to use the MENU button (centre on the left) instead of the encoder button, in the Bluetooth menu. I need to go through that menu and check it fully.
I've checked trainer over BT, screen dump to eepskye and raw telemetry relay over BT, still to test using eepskye sending controls to the radio over BT (I think that works on other radios).
Mike
I've posted updated firmware on the test versions thread, but it is in the
FIFTH post as when I tried to edit the first post, all but one of the attachments disappeared!
Hello. My friend. I have question.
If i solder Bluetooth hc05 on that board my qx7.
So i can send my telemetry to Droid planner with phone?
Please help
Re: Taranis QX7 bluetooth
Posted: Mon Oct 15, 2018 10:05 pm
by MikeB
If you have ersky9x firmware installed, then the raw telemetry data may be sent out over bluetooth. I have no idea if "Droid planner" can handle the raw data.
Mike
Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 12:34 am
by abdulfpv
If i use frsky dash board can i read with that bluetooth.
So my part like This
Omnibus f4 send telemetry with receiver r9mini
In my qx7 use module r9m and read telemetry via remote in open Tx.
I want bride my telemetry to. The bluetooth
So. I can read in my phone use dashboard frsky app.
Or can i use usb from remote to my phone
Thanks
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Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 6:29 am
by jhsa
I think the old Frsky dashboard app for android can only do D8 telemetry. So it will only work with a DJT or DHT modules.
João
Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 7:02 am
by Kilrah
Correct.
Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 7:29 am
by abdulfpv
If r9m module in tx rx i solder that module blue tooth
Can i conect with ez gui
Or anything app on android. So i can see altitude gps etc with my phone android.
Can you give me info.
Thanks [emoji106]
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Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 7:44 am
by Kilrah
I do not believe any android app supports the smart port protocol at this point.
Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 7:46 am
by abdulfpv
So what must i do to convert tx rx in my module so i can read telemetry via Android
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Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 9:32 am
by jhsa
You would have to write an app for android that supports it
João
Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 12:20 pm
by abdulfpv
http://www.efly.co.il/forums/showthread.php?t=63751
You must see that
Tx rx from modul change to. Serial port and send bluetooth to Android app
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Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 1:42 pm
by Kilrah
As was explained to you this dates back ftom 2013 and is for the old D*T modules and the D8 system. Does not work with the new X stuff and there is no equivalent for the new gear at this point.
Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 1:45 pm
by abdulfpv
If i use r9m convert rs232 then output serial tx rx to bluetooth hc-05
So Droid planner and etc app can read telemetry from that serial
How about that [emoji120]
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Re: Taranis QX7 bluetooth
Posted: Tue Oct 16, 2018 3:05 pm
by Kilrah
Different protocol. Won't work.
Re: Taranis QX7 bluetooth
Posted: Wed Oct 17, 2018 12:35 am
by abdulfpv
https://youtu.be/zOksCqtIL4s
This is smart protocol
Take from taranis telemetry in the back radio then conect to bluetooth hc-05 or hc06 and send to the phone with droid planner
But in that video dont explain how to Do That
You say different protocol but smart port can read.
Please you see the video maybe you can give me tutorial
Thanks
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Re: Taranis QX7 bluetooth
Posted: Wed Oct 17, 2018 6:10 am
by Kilrah
Someone apparently made a smart port to mavlink converter with an arduino. But there is no documentation and the link he gave for it doesn't exist anymore, so I guess you'll either have to find someone else who did the same or do it yourself.