1 Please read the release notes carefully and upgrade INAV Configurator available at [Chrome Store](https://chrome.google.com/webstore/detail/inav-configurator/fmaidjmgkdkpafmbnmigkpdnpdhopgel). You can also use [Configurator built as a native MacOS or Windows application](https://github.com/iNavFlight/inav-configurator/releases/tag/1.7.3).
3 INAV is and will remain open-source and free, but you are more than welcome to [support the development](https://inavflight.github.io/supporting-inav/).
5 This release was supported by our awesome sponsors [CarbonBird.com](http://www.CarbonBird.com), [Airbot](http://shop.myairbot.com/) and [ADPM Drones](http://www.adpm.pro/).
9 - OSD blinking doesn't work [#2088]
10 - No I2C available on Matek F405-OSD [#2047]
14 This release is the last release featuring F1-based boards (NAZE, CC3D, AirHero32). They don't have enough memory and CPU power to make use of new code. Support is not removed from source tree, DIY-ers are welcome to build their own setups.
16 Bugs that are related to limited memory and/or CPU power on those boards won't be fixed. Functionality issues will only be fixed if they would be reproducible on more powerful F3/F4/F7 targets.
18 ## CLI parameter renaming / new parameters
20 New parameters have been introduced. Some CLI parameters were renamed to support new features or to better reflect their meaning:
22 | Old name | New name(s) |
23 |------------------------|----------------------------------------------------------------|
24 | `i2c_overclock` | `i2c_speed` |
25 | - | `cpu_underclock` |
26 | - | `smartport_fuel_percent` |
28 ## I2C bus speed selection
30 Some sensors (especially cloned barometer/compass sensors) are reported to work unreliably on default 400kHz speed. New `i2c_speed` setting allows to reduce I2C clock rate to 200kHz and 100kHz to allow these picky sensors to function properly. Overclocking to 800kHz is also possible but not recommended.
32 If on your board compass/baro sensor is not recognized or hangs (usually indicated by rapidly increasing I2C error count) please try setting `i2c_speed` to 200KHZ before reporting a bug.
34 ## Underclocking for F1/F3 targets
36 F1/F3 boards are working on 72MHz clock which may interfere with 433MHz long range RC control systems. A new CLI option (`cpu_underclock`) for F1 and F3-based targets allows user to select between 72MHz (default) and 48MHz CPU clock. Should theoretically reduce interference to 433MHz LRS systems.
38 Other clock speeds are not possible because native USB will only function with 72/48MHz system clock speed.
40 Use caution - lower CPU speed means that you'll probably have to slow down looptime as well to keep CPU usage within sane limits.
44 - [Omnibus F7 - highly experimental](https://store.myairbot.com/flight-controller/omnibus-f7/omnibusf7.html)
45 - [SPRACINGF4EVO](http://seriouslypro.com/spracingf4evo)
49 - Support for MTK GPS automatic configuration
50 - New experimental DIY sonar-to-I2C converter support (https://github.com/iNavFlight/INAV-Rangefinder-I2C-interface)
51 - MatekF405 boards now support common I2C baro/compass sensors. Note that MatekF405 OSD board doesn't have I2C outputs so only MatekF405 AIO board can benefit from the change
52 - Add airspeed indication to OSD
53 - Add analog pitot sensor support for all F3/F4 targets
54 - Support for VL53L0X laser rangefinder (short range)
55 - Add RunCam Split control via RC radio
57 - AIRMODE now available as a feature to have it always enabled (recommended for airplanes)
58 - QMC5883 compass support (pin-to-pin compatible to HMC5883L sensor, used in some Chinese GPS modules)
59 - Multiple Smartport telemetry improvements
60 - Add support for UK mode units in the OSD (Show the speed in mp/h while using metric for other values)
61 - Speed up blackbox downloading. Now downloading full 8Mb dataflash takes mere minutes.
65 - Fix ledstrip on Omnibus target
67 - Fix OSD crosshair blinking
69 - Fix feature bits being reset when exiting CMS
70 - Fix bug with UK units in OSD
71 - Fix horizon drift bug on some boards with OSD
72 - Fix altitude control not working under 5m altitude on airplanes
73 - Fix swapped values for `frsky_unit` in CLI. Dumps from previous versions should be modified to change `IMPERIAL` to `METRIC` and viceversa before restoring them on INAV >= 1.7.3.
74 - Fix auto re-arm after landing issue when using switch-arming and landing with zero throttle in RTH & auto-disarm
75 - Fix BlueJayF4 gyro not detected
79 @martinbudden, @stronnag, @fiam, @DzikuVx, @oleost, @Schalonsus, @adtinnis, @sambas, @teckel12