Devo 12s 3in1 / 4in1 RF module neat installation.

the thread is getting large, and while there are a couple of subjects being broached just now they all pertain to the 3in1/4in1 modules.

thanks for the info, yeah once I have more time to look into it properly I'll certainly post in the s-fhss thread or post a bug, i just wanted to test the x100 with the original tx first to ensure it's not an issue with the quad itself. tonight was just a quick test of the module's cc2500 after cmPang asked if I had tried binding to any frsky d series rx's due to him needing to use the frequency adjustment for the first time with any of the *in1 modules.

as it seems the hardware issues have mostly been ironed out by the manufacturer perhaps a new thread for discussion on these boards is in order?

hh, noted and thx

Hello friends,

just got the following informations from seller about this module:
www.ebay.de/itm/111959743183?euid=bfc936...2&cp=1&sojTags=bu=bu

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Hello,
The range is:
C2500: V8FR receiver with Frsky protocol,about 240m.
A7105: WLToys V911 helicopter with Flysky 8 ch receiver,based on Flysky protocol,about 240m.
CYFR6936: Spektrum MCPX helicopter with DSM2 protocol,Walkera SUPERCP helicopter with DEVO protocol,about 200m,
NRF24L01: WLToys V977 helicopter with KN protocol,use Walkera DEVO transmitter,about 200m (If equipped with MCU baseplate,only 50m). Hisky HCP100S helicopter with Hisky protocol,about 70m.

For antenna both 2 db, 5db are suitable , usually we use 2db-3db
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Please, let me recommend to use an extra DC DC 3.3 voltage regulator (my match was approx. 670 mA - using PA activated in tx.ini / hardware.ini).
Hope it helps somebody.

Regards.

Very bad range. My FS-i6 / TGY-i6 transmitter with iA6B has a range of around 2km according to most tests. I have been flying LoS only, and with works fine at 1000 meters.

note that the provided results are ranges on the ground. in general, air range at least five to ten fold..

i have zero range issue after one month's heavy flying

Why is that, should not the parameters be the same for the same module and different FrSky Receivers? On the Original FrSky modules and the Taranis there is no way and no need to do that. Guess they have matched crystals or are pretuned. But stil that should be always to the same freq. so the tuning should be the same for all FrSky models in my devo as well or?

I installed a 3in1 a month ago as per the instructions on banggood. I have read that there may be issues with the voltage regulators working out of spec supplying the 3in1 so I have ordered an AMS1117-3.3 to install on the main module pins 6 and 7 as suggested by slipstream in the link below. I am waiting for the regulator to arrive but have started having binding issues with my H8 Mini (Bayang NF24L01). The quad flashing so it is receiving the binding instruction but then it does not bind. I have two H8 minis and one is worse than the other. I have installed the latest nightly build but that doesn't help. My XK K110 binds with no problems but that is using CC2500. Sorry if this is posted in the correct thread but I suspect it is an 3in1 issue.

www.deviationtx.com/forum/6-general-disc...evo-power-regulators

Please ignore my post I just downloaded a different model file and it binds perfectly now. not sure what went wrong with my old model file. Obviously not a 3in1 issue.

is there any news?

HappyHarry wrote: I just tried my devo version 4in1 with both my rx-f801 and rx-f802 frsky protocol rx's and both bound no problem without requiring any freq fine/course changes at all, but I'm having some issues with my xk x100 and the s-fhss protocol that I'm going to have to look into when I have more time, but basically I can get it to bind from freq-fine +22 up to freq-fine +97, but once I swap the quads battery, power cycle or press re-init on the tx it wont re-bind again unless I go into the options and move freq-fine up or down 1 digit, very strange :/

In order to work with Frsky original TX and different CC2500 modules(devo multiprotocol) on F801/F802 frsky compatibles receivers code I introduced an autotuning routine on base channel at bind.So they will not be affected by channel offset.In fact it may work better. Even Frsky original TX and RX are not so perfect tuned each other.There is still a slight offset.probably not for all but was observed when testing.

that would certainly explain why I had no issues, I'll need to try and bind to some of my x series rx's and see how that goes.

nice work on the rx's by the way, I'm very impressed with their performance

I got bad luck, my new devo version 4in1 won't bind with Orange SF700S, I tried Freq-fine from +127 - -127
but it works ok with frsky X4RSB (FrskyX protocol) no Freq-fine tuning needed and Skyartec protocol also works fine.

have you also tried freq-course?

HappyHarry wrote: have you also tried freq-course?

Yes, I did , but can not find a combination could bind.
I tried Orange SF700S and XK K100 3D quad.

Midelic, I'd like to know do you need feedback from RX for this kind of tuning to work? And also, could you point me to specific piece of code doing the tuning.

No feedback from RX The rx is tuned to TX base frequency(on F801/F02) software.On original is done by carefully hardware parts selection.The TX at bind broadcasts channel 0 on base frequency.
The base frequency is set at start with 3 registers.
cc2500_writeReg(CC2500_0D_FREQ2, 0x5C); // reg 0x0D
cc2500_writeReg(CC2500_0E_FREQ1, 0x76); // reg 0x0E
cc2500_writeReg(CC2500_0F_FREQ0, 0x27); // reg 0x0F

on Frslky 0x5C7627 corresponding to
Base frequency = 2404 MHz.This is the start frequency channel 0 that all the other hopping channels are calculated from

If the frequency is not 2404 Mhz and is higher or lower(because the crystal or caps used have high tolerance) with +/210 Khz there is one register to tweak

cc2500_writeReg(CC2500_0C_FSCTRL0,(uint8_t)offset);//second complement in register
offset has values from -127 to +127
In deviation and mullti offset is the " fine" variable.

On rx side I set the rx on channel zero
cc2500_writeReg(CC2500_0A_CHANNR, 0);

and sweep all offset range(from -127 to +127) and listen for while(each offset every 50-100ms)
if receiving data or not receiving anythng jump to the next offset .
From the entire offset range I select the ones with best LQI(link quality indicator)

You can be very precise like that and get the exact middle(means the frequnecy which has the higher energy usually is close to the middle of the channel bandwitdth) of the channel zero.
some code you\ll find here
www.rcgroups.com/forums/showpost.php?p=21898893&postcount=95
also some more explanation;
www.rcgroups.com/forums/showpost.php?p=21879022&postcount=64

dc59 wrote:

HappyHarry wrote: have you also tried freq-course?

Yes, I did , but can not find a combination could bind.
I tried Orange SF700S and XK K100 3D quad.

this may be similar to the issue I had with the xk x100 binding, see this post here for a ult7e build by victzh that fixed it for me >> www.deviationtx.com/forum/builds/5569-xk...o-10?start=140#50756

HappyHarry wrote: this may be similar to the issue I had with the xk x100 binding, see this post here for a ult7e build by victzh that fixed it for me >> www.deviationtx.com/forum/builds/5569-xk...o-10?start=140#50756

There is something different, you can get the quad to bind from freq-fine +22 up to freq-fine +97, but I can not bind with any freq-fine value.

Thanks, midelic. Unfortunately it will not help us to use this method on the TX side. Maybe it makes sense to repeat packets on varying frequencies for a while to prime the RX. Theoretically, as S-FHSS packets contain frequency code the smart RX can make an adjustment.

Yes on TX side will not help much For this reason was introduced "fine " and coarse variables.Give values to tx offset/ to match the base frequency of RX.In fact when given different values to offset is doing that ,....repeating packets at bind on different frequencies around the base frequency,The offset is doing just the name implied is offsetting the base frequency with a fixed amount.How ever is not very precise method is very rough.If you cannot evaluate the LQI you can still hit the channel but possible on the channel edge where the energy transmitted is not very high which may lead to reduced range or missing hopping channels from time to time.
When I adjust the fine frequency on my TX I used together with RSSI at fixed distance to find the sweet spot.

I have an idea I will test when I get back home,I can calculate tle LQI on telemetry frames and see the values on TX side.. In base of that we can adjust the offset values(fine variable) to match the best LQI We can use telemetry frames LQI like fed back for quality reception.This way we can get accurate enough the channel middle.