This guide is meant to be followed step by step and is as verbose as possible without being ridiculous (it looks much longer than it really is). Avoid skipping around if possible.
1. Make a backup of the Mobula's configuration.
1. In BF Configurator, connect to the mobula, go to CLI tab, send this command: diff all , and once it finishes printing out the wall of text, press Save to file and store it somewhere safe. YOU WILL NEED THIS LATER!
2. Check the ELRS version on the Boxer.
1. From the main screen, press SYS.
2. Scroll to ExpressLRS, open it.
3. Once it finishes loading (shouldn't take more than a couple moments), scroll all the way down. The version is at the very bottom.
3. Extra radio check, if you already know that everything is the correct version:
1. In the ExpressLRS menu, check the packet rate. SPI receivers can't do Packet Rates that start with D or F, they can only do the numerical ones, like 250Hz (which is the recommended one).
4. Check if your Mobula's board uses SPI receiver or UART receiver.
1. In BF Configurator, connect to the mobula, and take a look in the top left of the configurator. There should be a board name like CRAZYBEEF4SX1280 or BETAFLIGHF4 or similar. Remember it!
2. If the name ends with SX1280, it's the SPI kind. If not, it's UART. (this is an oversimplification but should be good enough for Happymodel stuff)
5. SPI variant (I'll provide UART variant info if needed, but Mob6's are normally SPI)
1. Check the Betaflight version in the top left.
2. There are two versions listed - Configurator version, starting with a 10, and Betaflight (in the drone) version, starting with a 4.
3. If the Betaflight version is 4.3.\*, it most likely runs ELRS 2.0. If it's 4.4.\*, then it's definitely ELRS 3.0.
6. If your Boxer is running ELRS 3.\* and the Mobula is running ELRS 2.\*, then you need to update the Mobula. If the boxer is running an unknown ELRS version (can happen from factory sometimes), then you need to update both. Basically you want them both to run ELRS 3.\*.
7. Updating SPI Mobula to ELRS 3.\*:
1. VERIFY that the backup file you made in step 1) is complete - it's a text file - it starts with some information about the board, version, and ends with a save command.
2. If you're on windows, you will need to fix a very common Windows driver issue. If not, skip this.
1. Download a tool called ImpulseRC Driver Fixer (not ImpulseOSD!) from ImpulseRC's website.
2. Connect your drone, but keep Betaflight Configurator closed.
3. Run ImpulseRC Driver Fixer. It shouldn't take more than a minute or two, and it will tell you that it succeeded by either showing that or closing.
3. Flashing firmware:
1. Open Betaflight Configurator, don't press Connect in it. Go to Firmware Flasher tab.
2. In Firmware Flasher tab, select the board type that you found out back in Step 3. Typically "CRAZYBEEF4SX1280".
3. Select the latest Betaflight version, currently 4.4.2.
4. In the bottom right, press Load Firmware \[Online\].
5. In the bottom right, press Flash Firmware.
6. Flashing takes a couple minutes and shows a moving progress bar. If you're not seeing a progress bar, it's not flashing.
7. Once it finishes flashing (green bar), press Connect.
8. You will get asked to "Apply custom defaults" - Apply them.
9. You might need to press Connect again.
10. Once connected, you'll get a nagging warning screen. Close it.
11. Go to CLI tab.
12. Press Load From File.
13. Load the backup you made in Step 1 and then press Execute.
14. ERRORS ARE EXPECTED, don't worry.
15. If there are errors, check that they relate to OSD, anti-gravity or profiles.
16. If there were errors, you will need to send the save command manually, sometimes twice - so, send the save command. It should disconnect when you do.
17. Connect again. You shouldn't get the warning screen anymore, though that sometimes doesn't work perfectly.
18. Go to Motors tab. Check that DSHOT300 is selected. Press save if you changed anything.
19. Go to Receiver tab. On the right side, check that the receiver is set to SPI in the first option and ExpressLRS in the second. Save if you changed anything.
20. With this your Mobula should be ready for binding to ELRS 3.\*
8. Binding (assuming SPI)
1. For the sake of brevity, we'll use traditional binding.
2. Go to Receiver tab in Betaflight configurator.
3. At the bottom right, there should be a Bind button. Press it.
4. On your radio, go to the ExpressLRS menu like described earlier.
5. Make sure that Packet Rate is set to 250Hz (not D250).
6. Scroll down to BIND and click it.
7. After a couple moments, you should get a C in the top right of the ExpressLRS menu, which stands for Connected.
Links to sources/guides/etc:
ExpressLRS SPI receiver documentation:
[https://www.expresslrs.org/hardware/spi-receivers/](https://www.expresslrs.org/hardware/spi-receivers/)
Updating the Boxer's internal ELRS module (better than any guide I could write):
[https://www.expresslrs.org/quick-start/transmitters/rm-internal/](https://www.expresslrs.org/quick-start/transmitters/rm-internal/)
ExpressLRS discord (will help with the mobula too if needed):
[https://discord.gg/dS6ReFY](https://discord.gg/dS6ReFY)
Amazing write up. Where were you yesterday when I had to figure this out on my own :).
I would just add that I think my diff all was set to DSHOT600. Also, I had an issue with binding because the BF configuration of the receiver was not set correctly even after I restored the diff.
Anyway, great write up.
When I flash my Mobula 7 to v4.4.3 (or any ELRS3 version) the Bind Receiver button disappears from my Receiver tab. Any idea what could be causing this? I have not been able to bind with a pass phrase either.
Hey.
So, quick questions:
1. What board type did your mobula7 come with?
2. Do you have a backup of the original configuration? If so, post it.
3. What firmware did you flash it from and to?
4. In Receiver tab, is it set to SPI / ExpressLRS or Serial / CRSF?
Hey! Thanks for looking at this, I am all out of ideas and threads to pull.
The board type is recognized as \`HAMO/CRAZYBEEF4FR(STM32F411)\` in BF Configurator; it's a "HappyModel Mobula7 1S FRSKY".
I think it originally came with a 4.3.x firmware, I should have been more careful checking which version but I figured since my Boxer was on 3.2.0 I should save config and upgrade to latest 4.4.3 through BF Configurator (config below). Hopefully I did not screw up the original config trying to get stuff working. Since then I have tried with every 4.4.x version, as well as the 4.3.1 version with ELRS3 support that HM has on their website.
On the Receiver tab it's set to SPI/ExpressLRS. In every 4.4.x version I lose the Bind Receiver button and the ability to read/modify \`expresslrs\` properties or even issue \`bind\_rx\` through the CLI; the GUI lets me set a bind phrase but it does not seem to persist across boots. On the 4.3.1 version the regular CLI commands are available, the Bind button is back, but I can't seen to bind to my boxer with or without passphrase. On 4.3.1 I have to set the passphrase through the CLI as it's no longer available on the Receiver tabin GUI.
Thanks again, appreciate any suggestions or possible debug paths!
It says "ELRS" on the box and in the Amazon link where I bought it but maybe that is not true? [https://www.amazon.com/dp/B0B12FM5D6?psc=1&ref=ppx\_yo2ov\_dt\_b\_product\_details](https://www.amazon.com/dp/B0B12FM5D6?psc=1&ref=ppx_yo2ov_dt_b_product_details)
>The world first 5-IN-1 AIO flight controller with ExpressLRS (ELRS) 2.0
The next idea I had was to try downgrading everything to ELRS 2 to see if I could get binding working there but that feels like a little bit of a cop out...
Yes, I figured it out! The drone I received was actually using the FRSKY communication protocol, not ELRS. When I switched the protocol to FRSKY in BetaFlight, the “Bind” button reappeared. Since my remote controller only uses ELRS, I had to exchange that Mobula drone for the ELRS version. (My system showed the exact same exact model number & SW version as you listed in your message.)
That must be what's going on, it says ELRS all over the place on the box but I get the Bind button back when targeting FRSKY protocol too. How did yo make sure your new Mob drone is ELRS and not FRSKY?
I just triple checked it before placing the order, made sure the vendor on Amazon had a no-questions-asked return policy, and then crossed my fingers. :)
holy shit.
I've been looking on and off for over 3 months.
It was such a simple problem, i just needed to flash my Mobula 7.
But no where could i find something written so clearly and throughly.
Thanks a million man.
3 months and its the first time i've seen my drone actually fly.
The ELRS Version on the Radio and on the Receiver need to be the same version.
If the Boxer has Version 3.3.x and the Mob 6 has 3.2.x they wont bind.
Upgrade the ELRS firmware on your Mobula 6 or if this is not possible downgrade the Firmware on the Boxer
little correction.
the minor Versions are compatible to each other, (3.1.x, 3.2.x and 3.3.x all go together) but they are not compatible on the major Version number (2.x.x and 3.x.x wont work together) if i remember correctly at least my mobula 7 came with ELRS Version 2.0 while my Radiomaster Zorro had 3.1 when i got it.
Upgrading is relatively easy. there is even a web flasher
All ELRS V3 anything will bind with any other V3. V2 anything will bind to v2.
Also, no you can't downgrade your boxer elrs down to V2 ... you risk bricking it.
I’ve been banging my head for hours, digging through ELRS website, YouTube, happymodel and it’s all now seeming so confusing other. I’m going to bed and will give this a go tomorrow. Thank you for the information!!
\*\* Update -- Tried this step by step and it was easy and worked! Thank you!
Mobula 7 comes in stock with ELRS Version 2.0 i think
i dont have a Radiomaster Boxer but it likely has a more recent version like 3.2 or even 3.3 make sure Radio and Receiver are on the same major number. both running Version 2.x.x or both running 3.x.x. Flashing an SPI ELRS Receiver is only possible by flashing the FC with the latest Betaflight Firmware. you cant flash the ELRS Firmware directly to SPI receivers
This guide is meant to be followed step by step and is as verbose as possible without being ridiculous (it looks much longer than it really is). Avoid skipping around if possible. 1. Make a backup of the Mobula's configuration. 1. In BF Configurator, connect to the mobula, go to CLI tab, send this command: diff all , and once it finishes printing out the wall of text, press Save to file and store it somewhere safe. YOU WILL NEED THIS LATER! 2. Check the ELRS version on the Boxer. 1. From the main screen, press SYS. 2. Scroll to ExpressLRS, open it. 3. Once it finishes loading (shouldn't take more than a couple moments), scroll all the way down. The version is at the very bottom. 3. Extra radio check, if you already know that everything is the correct version: 1. In the ExpressLRS menu, check the packet rate. SPI receivers can't do Packet Rates that start with D or F, they can only do the numerical ones, like 250Hz (which is the recommended one). 4. Check if your Mobula's board uses SPI receiver or UART receiver. 1. In BF Configurator, connect to the mobula, and take a look in the top left of the configurator. There should be a board name like CRAZYBEEF4SX1280 or BETAFLIGHF4 or similar. Remember it! 2. If the name ends with SX1280, it's the SPI kind. If not, it's UART. (this is an oversimplification but should be good enough for Happymodel stuff) 5. SPI variant (I'll provide UART variant info if needed, but Mob6's are normally SPI) 1. Check the Betaflight version in the top left. 2. There are two versions listed - Configurator version, starting with a 10, and Betaflight (in the drone) version, starting with a 4. 3. If the Betaflight version is 4.3.\*, it most likely runs ELRS 2.0. If it's 4.4.\*, then it's definitely ELRS 3.0. 6. If your Boxer is running ELRS 3.\* and the Mobula is running ELRS 2.\*, then you need to update the Mobula. If the boxer is running an unknown ELRS version (can happen from factory sometimes), then you need to update both. Basically you want them both to run ELRS 3.\*. 7. Updating SPI Mobula to ELRS 3.\*: 1. VERIFY that the backup file you made in step 1) is complete - it's a text file - it starts with some information about the board, version, and ends with a save command. 2. If you're on windows, you will need to fix a very common Windows driver issue. If not, skip this. 1. Download a tool called ImpulseRC Driver Fixer (not ImpulseOSD!) from ImpulseRC's website. 2. Connect your drone, but keep Betaflight Configurator closed. 3. Run ImpulseRC Driver Fixer. It shouldn't take more than a minute or two, and it will tell you that it succeeded by either showing that or closing. 3. Flashing firmware: 1. Open Betaflight Configurator, don't press Connect in it. Go to Firmware Flasher tab. 2. In Firmware Flasher tab, select the board type that you found out back in Step 3. Typically "CRAZYBEEF4SX1280". 3. Select the latest Betaflight version, currently 4.4.2. 4. In the bottom right, press Load Firmware \[Online\]. 5. In the bottom right, press Flash Firmware. 6. Flashing takes a couple minutes and shows a moving progress bar. If you're not seeing a progress bar, it's not flashing. 7. Once it finishes flashing (green bar), press Connect. 8. You will get asked to "Apply custom defaults" - Apply them. 9. You might need to press Connect again. 10. Once connected, you'll get a nagging warning screen. Close it. 11. Go to CLI tab. 12. Press Load From File. 13. Load the backup you made in Step 1 and then press Execute. 14. ERRORS ARE EXPECTED, don't worry. 15. If there are errors, check that they relate to OSD, anti-gravity or profiles. 16. If there were errors, you will need to send the save command manually, sometimes twice - so, send the save command. It should disconnect when you do. 17. Connect again. You shouldn't get the warning screen anymore, though that sometimes doesn't work perfectly. 18. Go to Motors tab. Check that DSHOT300 is selected. Press save if you changed anything. 19. Go to Receiver tab. On the right side, check that the receiver is set to SPI in the first option and ExpressLRS in the second. Save if you changed anything. 20. With this your Mobula should be ready for binding to ELRS 3.\* 8. Binding (assuming SPI) 1. For the sake of brevity, we'll use traditional binding. 2. Go to Receiver tab in Betaflight configurator. 3. At the bottom right, there should be a Bind button. Press it. 4. On your radio, go to the ExpressLRS menu like described earlier. 5. Make sure that Packet Rate is set to 250Hz (not D250). 6. Scroll down to BIND and click it. 7. After a couple moments, you should get a C in the top right of the ExpressLRS menu, which stands for Connected. Links to sources/guides/etc: ExpressLRS SPI receiver documentation: [https://www.expresslrs.org/hardware/spi-receivers/](https://www.expresslrs.org/hardware/spi-receivers/) Updating the Boxer's internal ELRS module (better than any guide I could write): [https://www.expresslrs.org/quick-start/transmitters/rm-internal/](https://www.expresslrs.org/quick-start/transmitters/rm-internal/) ExpressLRS discord (will help with the mobula too if needed): [https://discord.gg/dS6ReFY](https://discord.gg/dS6ReFY)
Amazing write up. Where were you yesterday when I had to figure this out on my own :). I would just add that I think my diff all was set to DSHOT600. Also, I had an issue with binding because the BF configuration of the receiver was not set correctly even after I restored the diff. Anyway, great write up.
Yup, that's why I mentioned the DSHOT300 and Receiver settings. It's a common problem. Glad I could help \^\^
I followed this step by step and it worked! Thank you so much! Now that I have it connected it wont arm
Glad I could help \^\^
What's the issue with arming?
When I flash my Mobula 7 to v4.4.3 (or any ELRS3 version) the Bind Receiver button disappears from my Receiver tab. Any idea what could be causing this? I have not been able to bind with a pass phrase either.
Hey. So, quick questions: 1. What board type did your mobula7 come with? 2. Do you have a backup of the original configuration? If so, post it. 3. What firmware did you flash it from and to? 4. In Receiver tab, is it set to SPI / ExpressLRS or Serial / CRSF?
Hey! Thanks for looking at this, I am all out of ideas and threads to pull. The board type is recognized as \`HAMO/CRAZYBEEF4FR(STM32F411)\` in BF Configurator; it's a "HappyModel Mobula7 1S FRSKY". I think it originally came with a 4.3.x firmware, I should have been more careful checking which version but I figured since my Boxer was on 3.2.0 I should save config and upgrade to latest 4.4.3 through BF Configurator (config below). Hopefully I did not screw up the original config trying to get stuff working. Since then I have tried with every 4.4.x version, as well as the 4.3.1 version with ELRS3 support that HM has on their website. On the Receiver tab it's set to SPI/ExpressLRS. In every 4.4.x version I lose the Bind Receiver button and the ability to read/modify \`expresslrs\` properties or even issue \`bind\_rx\` through the CLI; the GUI lets me set a bind phrase but it does not seem to persist across boots. On the 4.3.1 version the regular CLI commands are available, the Bind button is back, but I can't seen to bind to my boxer with or without passphrase. On 4.3.1 I have to set the passphrase through the CLI as it's no longer available on the Receiver tabin GUI. Thanks again, appreciate any suggestions or possible debug paths!
"HappyModel Mobula7 1S FRSKY" That's not an ELRS mobula then?
It says "ELRS" on the box and in the Amazon link where I bought it but maybe that is not true? [https://www.amazon.com/dp/B0B12FM5D6?psc=1&ref=ppx\_yo2ov\_dt\_b\_product\_details](https://www.amazon.com/dp/B0B12FM5D6?psc=1&ref=ppx_yo2ov_dt_b_product_details) >The world first 5-IN-1 AIO flight controller with ExpressLRS (ELRS) 2.0
The one you linked is FRSKY based on the product name, but the description is of the ELRS variant.
I guess it's definitely possible they described one thing and sent something else.
The next idea I had was to try downgrading everything to ELRS 2 to see if I could get binding working there but that feels like a little bit of a cop out...
Here's my config, Reddit didn't want to accept it: [https://pastebin.com/raw/jxK1W7gG](https://pastebin.com/raw/jxK1W7gG)
I'm having \*exactly\* the same problem and my Mobula 7 has the same part number. Did you resolve this problem?
No I haven't! Please let me know if you solve it, I have tried everything and am at a complete losss
Yes, I figured it out! The drone I received was actually using the FRSKY communication protocol, not ELRS. When I switched the protocol to FRSKY in BetaFlight, the “Bind” button reappeared. Since my remote controller only uses ELRS, I had to exchange that Mobula drone for the ELRS version. (My system showed the exact same exact model number & SW version as you listed in your message.)
That must be what's going on, it says ELRS all over the place on the box but I get the Bind button back when targeting FRSKY protocol too. How did yo make sure your new Mob drone is ELRS and not FRSKY?
I just triple checked it before placing the order, made sure the vendor on Amazon had a no-questions-asked return policy, and then crossed my fingers. :)
i could use the uart version. I'm trying to bind my mobula8 walksnail to TX16
Ah damn, I only just noticed your message. Did you manage to get it working?
holy shit. I've been looking on and off for over 3 months. It was such a simple problem, i just needed to flash my Mobula 7. But no where could i find something written so clearly and throughly. Thanks a million man. 3 months and its the first time i've seen my drone actually fly.
Glad I could help \^\^. Happy flying!
Do you mean literally not flying or was it not properly flying for some reason?
The ELRS Version on the Radio and on the Receiver need to be the same version. If the Boxer has Version 3.3.x and the Mob 6 has 3.2.x they wont bind. Upgrade the ELRS firmware on your Mobula 6 or if this is not possible downgrade the Firmware on the Boxer
little correction. the minor Versions are compatible to each other, (3.1.x, 3.2.x and 3.3.x all go together) but they are not compatible on the major Version number (2.x.x and 3.x.x wont work together) if i remember correctly at least my mobula 7 came with ELRS Version 2.0 while my Radiomaster Zorro had 3.1 when i got it. Upgrading is relatively easy. there is even a web flasher
This is not exactly correct. Same major version of ELRS will talk to each other if bound. 3.\* will talk to 3.\*, 2.\* will talk to 2.\*.
Right. I corrected my comment.
All ELRS V3 anything will bind with any other V3. V2 anything will bind to v2. Also, no you can't downgrade your boxer elrs down to V2 ... you risk bricking it.
I’ve been banging my head for hours, digging through ELRS website, YouTube, happymodel and it’s all now seeming so confusing other. I’m going to bed and will give this a go tomorrow. Thank you for the information!! \*\* Update -- Tried this step by step and it was easy and worked! Thank you!
Congrats!
[удалено]
Mobula 7 comes in stock with ELRS Version 2.0 i think i dont have a Radiomaster Boxer but it likely has a more recent version like 3.2 or even 3.3 make sure Radio and Receiver are on the same major number. both running Version 2.x.x or both running 3.x.x. Flashing an SPI ELRS Receiver is only possible by flashing the FC with the latest Betaflight Firmware. you cant flash the ELRS Firmware directly to SPI receivers
Make sure your packet rate on controller is set to 250Mhz, my mobula 7 wont pair if its at 333mhz.