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May 21, 2015, 03:21 PM
Registered User
HI flipflap. i have tried to get data through usart, but i dont have on RX module..

APM usart 1 is configured to use speed 19200.
FW version 1.06
link is ok( i got ppm signal)

ive launched a mission planner make a common ground between RX, TX modules and APM. next i used a UART-to-usb converter.


so when i touch TX pin on APM itself- i get data( mission planner get updates);
when i touch RX pin on ULRS TX module - i also get data.

but when i touch TX pin on RX module - there is no data. Have you any ideas why?


thanks in advance!
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May 21, 2015, 03:30 PM
Registered User
Thread OP
Yes, the communication between APM and ULRS (plane side) is at 19200 bauds.

But communication between ULRS (ground side) and computer is at 115200 bauds.

So when you touch the pins of either the APM or ULRS on plane side, you get data (at 19200 bauds). But when you touch the pins on the ground side, you don't get anything (because you should listen at 115200 bauds)
May 22, 2015, 02:00 AM
Registered User
Thanks a lot for reply! So for now i have the following problem. My er9x transmitter have 38400 baud. And ulrs 115200. is it will be safe if i redefine baud rate on ulrs to 38400 or it will be better to change it on transmitter to 115200 which will give me almost 3% of error according to datasheet?
May 22, 2015, 03:12 AM
Registered User
Thread OP
I recommend not to change the baudrate on ULRS side, as there are many implications if this is changed. For example the exact timing required to send or receive data is important, as well as the baudrate value relative to the RF rate etc.

3% error on data rate from er9x should not be an issue.
May 22, 2015, 03:44 AM
Registered User
Quote:
Originally Posted by flipflap
I recommend not to change the baudrate on ULRS side, as there are many implications if this is changed. For example the exact timing required to send or receive data is important, as well as the baudrate value relative to the RF rate etc.

3% error on data rate from er9x should not be an issue.

Thank you! its a pleasure to communicate with you!
May 22, 2015, 09:53 AM
Just call me Justin.
Quote:
Originally Posted by thefear
Thanks a lot for reply! So for now i have the following problem. My er9x transmitter have 38400 baud. And ulrs 115200. is it will be safe if i redefine baud rate on ulrs to 38400 or it will be better to change it on transmitter to 115200 which will give me almost 3% of error according to datasheet?
I tryed to change the rate in the source code. Didn't work so well. I use 115200 on my opentx and it works fine.
May 22, 2015, 12:21 PM
Registered User
Quote:
Originally Posted by jt41time
I tryed to change the rate in the source code. Didn't work so well. I use 115200 on my opentx and it works fine.

ive changed rate in my er9x-ardupilot to 115200 but there is still no data on screen. and now i try to understand where is the problem.


could you give me your .hex to flash my turnigy 9x?
Last edited by thefear; May 22, 2015 at 12:33 PM.
May 22, 2015, 02:01 PM
Constantly Confused
nanorapture's Avatar

100mw tx and 100mw rx work?


Thanks for the great software Ben! You are so patient with all the same questions coming every day!

After reading most of the first pages, i am still confused.

Could I use old Orange 100mw tx and 100mw rx i have laying around from a couple of years back to try to flash this new firmware to try it out? Or does the Tx at least have to be the newer 1w version?

I just want to try it out to see if it works at all. Not trying to get any range.

Thanks Flipflop!
May 22, 2015, 04:20 PM
Registered User
Thread OP
It's initially made for 1W TX + 1W "TX", but it's also possible to use it with a 100mW RX. This was done especially for quads which are sensitive to weight or have not enough room for the 1W TX.

But I prefer avoiding the 100mW "TX", use a 1W TX, which is actually more like a 400mW TX, and don't worry for the range.
May 23, 2015, 01:03 AM
Registered User
Corie's Avatar
Hi Ben, I just soldered and flashed a pair of uLRS 2 weeks ago but I seem to be developing early onset alzheimers - I can't remember now how to safely power the module with 5.5v to get closer to 1W of RF power. Do I simply connect 5.5v to the J1 VCC soldering pad to do this safely? I intend to power my module with a 5.5v sbec from my ground station. Will it require airflow / heat sink?

Also, I'm in the process of putting in a dedicated module in my ground station. I'll run wires down to put into my taranis. Must I connect all 5 of these pins? Or can I connect only the PPM and ground?

What voltage does the taranis normally output to the module? According to the picture, its 6V - is this correct?

Thanks so much.
Last edited by Corie; May 23, 2015 at 01:16 AM.
May 23, 2015, 03:50 AM
Registered User
Thread OP
So, to have higher power, only the RFM module must be powered at 5.5V, not the atmega or other parts. The PCB track that goes to the VCC pin of the RFM module must be cut, and then simply apply 5.5V on the VCC pin of the module.

See attached diagram to identify the VCC pin.

Notice it needs 5.5V to 6V for full power, 5V is already an improvement but is not full power.

No heatsink or airflow is required.

You can connect only the PPM and ground.

I'm not certain about the voltage Taranis provides, it would be preferable to measure to be sure.
Last edited by flipflap; May 23, 2015 at 05:30 AM.
May 23, 2015, 10:40 AM
Registered User
Corie's Avatar
Thanks.

I've been powering it directly from the Pixhawk telem port which I believe is 5v through the soldering pad at J1. Did I damage my module / should I revise it?
May 23, 2015, 11:13 AM
Registered User
Thread OP
Normally if it's a 1W module it should be fine. if the atmega was powered at 5v it sent 5V on the IO pins of RFM, which is bad, but usually not lethal.
May 23, 2015, 06:11 PM
Registered User
Corie's Avatar
Hi Ben,

thanks for the replies. I desoldered the VCC trace and replaced it with a 5V line as per your diagram.

My taranis outputs:
0V on the 6V pin.
7.2V on bat pin (my transmitter battery voltage)
0V on the Ant
3.7V on the PPM pin

I know you had stated that all I need to connect now is the PPM pin and the ground pin from my taranis to the J1 port of my module. How is the rest of the module (other than the 1W transmitter chip) getting it's power supply? Is it being powered through the 3.7V on the PPM pin?

Thanks

Steven
May 23, 2015, 09:09 PM
Wisconsin
Quote:
Originally Posted by Corie
Hi Ben,

thanks for the replies. I desoldered the VCC trace and replaced it with a 5V line as per your diagram.

My taranis outputs:
0V on the 6V pin.
7.2V on bat pin (my transmitter battery voltage)
0V on the Ant
3.7V on the PPM pin

I know you had stated that all I need to connect now is the PPM pin and the ground pin from my taranis to the J1 port of my module. How is the rest of the module (other than the 1W transmitter chip) getting it's power supply? Is it being powered through the 3.7V on the PPM pin?

Thanks

Steven
Just a reminder that the Taranis does not "power up" the module unless it is chosen in the model profile. i.e. the transmitter is set to "external".

Cheers
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