How to Upgrade to Betaflight 4.5? (Step-by-Step)

Betaflight 4.5 is right around the corner, currently still in release candidate testing but bringing some exciting new features that will improve performance and usability.

In this in-depth, step-by-step walkthrough, we’ll cover my full process for upgrading one of my quads from Betaflight 4.4 to the 4.5 release candidate in preparation for testing out the new functionality.

If you want to upgrade to 4.5 yourself when it drops to follow along with my upcoming testing videos, or just get access to the new features, this guide should equip you with everything you need to know. We’ll go through:

• Backing up your current configuration
• Downloading and installing Configurator
• Flashing the 4.5 firmware
• Reviewing build configuration options
• Transferring elements of your old configs
• Checking motors, rates and other settings
• Initial bench testing

So strap in and come along for an under-the-hood look at this crucial FPV quad upgrade process!

Back Up Your Configuration

The first thing you absolutely MUST do is back up your current config. Upgrading between major firmware versions is an unpredictable process, and things can easily go sideways. If that happens, you need a way to rollback to your perfectly tuned 4.4 quadcopter.

Here’s the process I use to create and safely store config backups every time before a firmware flash:

1. Connect to your quad’s flight controller in Configurator as usual
2. Go to the CLI tab
3. Type “diff all” and hit enter – this will dump your whole configuration to the CLI screen
4. Copy everything from “# diff all” to the end of the dump
5. Paste it into a text file and save as something like “4.4_backup_Chimera7Pro.txt”

I also like to open up the file and double check that the config actually saved properly. It’s rare, but I’ve had cases where the dump was empty due to an issue communicating with the FC.

The critical thing is that backup allows you to fully restore your quad to its previous state if things go sideways with the upgrade. So don’t skip it!

Install New Configurator

To upgrade to 4.5, you MUST be running the latest 10.10 release of Betaflight Configurator. This release contains updates on the software side to support communicating with 4.5 flight controllers.

As of writing this, Configurator 10.10 Release Candidate 2 is the newest available. To upgrade:

1. Open Configurator and go to the “Update & Install” tab
2. Check the box for “Show Development Releases” at the very bottom
3. 10.10 RC2 should appear in the updates list if you don’t already have it installed
4. Click “Install Update” and wait for the process to complete

Again by the time you actually upgrade to 4.5, there will likely be a full, non-release candidate 10.10 available. But ALWAYS make sure you’re on the latest Configurator before flashing new firmware!

Flash Betaflight 4.5 Firmware

Now on to the actual firmware upgrade! I’ll be stepping through the process to go from 4.4 to the 4.5 release candidate on my iFlight Chimera 7 Pro quadcopter.

Here is the full process:

1. Connect your radio receiver and battery so the quad is fully powered up
2. Plug into Configurator 10.10 on your PC
3. Go to the “Firmware Flasher” tab
4. Click “Choose File” and browse to the local 4.5 firmware file you downloaded
5. Enable “Full Chip Erase” to completely wipe the flight controller
6. Enable “Manual Baud Rate” and set to 256000 if it isn’t already
7. Click “Flash Firmware” and wait for the process to complete
8. You’ll get a prompt to “Reset Into DFU” – click yes and wait for the FC reset to complete
9. Finally click “Read Setup” and the “Flash Firmware” button will reappear after establishing communication with the board
10. The firmware flash is now complete!

One thing to watch out for is a potential communications issue after the flash where Configurator won’t reconnect properly to the FC. If this happens, just unplug and reconnect the USB cable a few times until you see device activity and can hit “Connect”.

Review Build Options

Betaflight 4.5 brings a new “cloud compile” functionality that allows for more customized firmware builds with unused features removed to reduce FC resource usage. When you flash a pre-built firmware file, you’ll get a pop-up like this:

Most users will be fine accepting the default options. But if you rely on any disabled features like SBus receiver connectivity, make sure to check here and enable those. I use Crossfire so left that default disabled with no issue.

The key things to consider are:

• Radio protocol (enable what you use)
• Motor protocol (e.g. DShot)
• Receiver connectivity like FPort
• Transponder support
• Additional peripheral support as needed

Get familiar with what these options mean if flashing pre-built firmware files. And when in doubt, build your own custom image with all features enabled instead!

Transferring Old Configs

After the flash, DO NOT just load your old config backup directly. Too many low level changes happen between major firmware versions for that to work properly.

Instead, we’ll go through the backup CLI dump line-by-line to selectively transfer safe settings like ports, OSD layout, rates, etc over to 4.5 manually.

Here’s my general rule of thumb on what can stay the same through an upgrade:

Generally Safe Options

• Ports & Serial Configs
• Feature Enables & Disables
• LED Settings
• OSD Configurations
• Modes & Channel Maps
• Rates & Expos

Requires More Caution

• PID Values
• Filter Settings
• Timer Configurations
• Motor Protocol Values

I tend to avoid copying things that alter lower level functionality, unless I fully recognize the value and know it’s compatible with the updated firmware. When in doubt, leave it out!

Let’s walk through this manual migration process now…

1. Open your backup config file and connect to your quad in Configurator after the firmware flash
2. Go to the CLI tab
3. Scroll through the backup config dump line-by-line to identify values that are safe to transfer
4. Copy those lines directly into the CLI terminal to recreate parts of your config

Here are some of the key options I elected to bring over for this 4.5 upgrade:

Port configs: Enables SmartAudio on UART2 for my video transmitter control among other ports

set serialrx_provider = CRSF
set serialrx_inverted = OFF
set serialrx_halfduplex = OFF
set aspsps_uart = NONE
set blackbox_device = SPIFLASH
set dshot_bidir = ON
set motor_pwm_protocol = DSHOT600
set motor_pwm_rate = 480
set vtx_band = 5
set vtx_channel = 6 
set vtx_power = 1
set vtx_low_power_disarm = OFF
set vtx_freq = 5740
set vtx_pit_mode_freq = 0
set vtx_halfduplex = OFF
set vtx_spi_bus = 20
set pinio_box = 40,41,255,255
set spektrum_spi_bus = 9
set pinio_config = 129,1,1,1
set led_inversion = 0
set dashware_mode = 0
set camera_control_key = 0
set adc_device = 2
set ibata_scale = 179
set ibata_offset = -37
set beeper_inversion = ON
set beeper_od = OFF
set beeper_frequency = 0
set beeper_dshot_beacon_tone = 2
set beeper_dshot_beacon_frequency = 2 
set usc_uart10_mode = 2
set usc_telem_uart10_inverted = OFF
set usc_telemetry_uart10_halfduplex = ON
set smartaudio_uart2_mode = 1
set smartaudio_uart2_inverted = OFF
set smartaudio_uart2_halfduplex = ON

Feature Enables: Turns on LED strips, GPS usage, and telemetry inversion for SmartPort

set led_strip = ON
set gps_provider = UBLOX
set gps_sbas_mode = AUTO
set gps_auto_config = ON
set gps_set_home_point_once = OFF
set telemetry_inversion = ON

Modes: Sets up my preferred aux switch channel mappings

set aux1 = 39
set aux2 = 43
set aux3 = 41
set aux4 = 42

Rates & Expo: Matches my pre-upgrade rate profile 1

set roll_rate = 108
set pitch_rate = 108
set yaw_rate = 108
set tpa_rate = 60
set tpa_breakpoint = 1250

And so on for additional OSD, LED, battery/voltage configurations I wanted to preserve.

The key things I avoided copying over were my old PIDs, gyro/D term filters, motor PWM parameters, and feedforward transitional settings. The defaults there provide a good starting point for tuning on 4.5 directly.

I did copy my rates over though as that is generally safe to bring between firmware versions!

Initial Setup Checks

After transferring over those old config elements, we need to initialize some additional 4.5 settings as well as run through general sanity checks before the maiden 4.5 flight.

Here are the steps I took along with some useful tips:

Calibrate Accelerometer

Any time you flash new firmware, get in the habit of calibrating your accelerometer values. After my partial config transfer, I placed the quad flat on the desk and went to the CLI tab:

calibrate accelerometer

Follow the on-screen instructions to rotate the quad through different orientations until complete. This ensures proper orientation for things like self-level modes.

Enable Bi-Directional DShot

Betaflight 4.5 continues improving support for bi-directional DShot communication from ESCs. That means telemetry data sent back for logging without needing external wires.

To enable, I went to the Configuration > Motors tab:

1. Flashed ESCs to latest firmware
2. Clicked “Enable Bi-Directional DShot” under “Bidirectional DShot Settings”

This automatically tweaks filter settings known to help bi-directional DShot performance too. Much simpler than the old CLI method!

Check Motor Direction

Any firmware flash has a small chance of flipping motor rotation direction. Before any test flight, it’s worth quickly running:

spin_motors

And verifying that each motor spins the direction you expect it to. Pay attention to the order as well in case that got rotated.

If any motors are backwards, flip the “Motor Direction is Reversed” switch next that motor in the Configuration > Motors tab.

Tune New Rate Profile

To play it safe on early flights, I created a custom rate profile 2 in addition to bringing my old profile 1 rates over. This way I could fly more conservative rates on the first packs before loading my full acro rates.

Easy to tweak the new rate profile 2 values in the Configuration > Rates tab for a simpler test flight. Just select “Profile 2” at the top first.

More Checks & Preflight

Past that initial configuring and checking, treat a 4.5 quad like you would any other pre-flight:

• Verify channels/switches in Receiver tab
• Confirm OSD looks correct
• Check GPS coordinates/sat count if equipped
• Do full rx range test
• Follow full pre-flight checklist

Then get out there and fly on a known-good battery while carefully evaluating any firmware changes!

Maiden Flight Impressions

I was running the Chimera 7 on 4.4 with RPM filtering disabled for a good while before this upgrade. The quad flew great like that, but the noisy motors and EMF interference with HD feeds were apparent.

Flashing everything over to 4.5 with RPM filtering enabled out of the box made a clear improvement in those areas with this build. And that’s running the same PIDs, rates, and overall tune as my well worn-in 4.4 setups.

I also took things easy on the maiden 4.5 packs given the upgraded firmware. Stuck to simple flows and maneuvers tracking response and feel. Turned off any rescue modes or new fancy features for now while focusing purely on general performance.

Overall, solid improvement even over an already well tuned rig thanks to:

• Smoother video feed with less interference
• Lower motor noise across throttle ranges
• No obvious performance hits out of the box (may change as testing progresses)

I ran a handful of packs like that to both settle in the new firmware and confirm that the essential flight characteristics didn’t suffer.

With everything looking good so far, it’s time to start playing with Betaflight 4.5’s new goodies! More testing to come there with in-depth looks at:

• RPM Filtering
• ESC Telemetry Setup
• GPS Rescue Changes
• 8K/4K PID Loop
• Feedforward Updates
• Configuration Overhaul

Conclusion

Betaflight 4.5 represents an incremental-but-meaningful step forward in flight performance, quality of life, and general usability improvements. Some key new features will also expand possibilities in areas like long range and cinematic builds.

Upgrading existing quads is straightforward IF you follow the right procedure:

1. Back up your config
2. Flash Configurator & Firmware
3. Transfer safe settings only
4. Sanity check motors, rates and other functionality
5. Test fly on old PIDs first

With this guide walking through my full upgrade and testing process, you should feel confident tackling a move to 4.5 yourself as well. Just take things slow and methodically on that initial 4.5 flight.

I can already tell the benefits are well worth it after just a bit of stick time. And I’m eager to push further experimenting with the new tools available and better base tune provided by this latest Betaflight release.

So get those backups created, Configurator updated, and join me for some 4.5 testing! Plenty more to explore with this new firmware and I’ll be breaking it all down right here on the blog.

Happy flying everyone!