diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/README.md b/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/README.md
deleted file mode 100644
index ea30f5b4ba..0000000000
--- a/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/README.md
+++ /dev/null
@@ -1,13 +0,0 @@
-# CubeBlack-solo variant of the CubeBlack Flight Controller
-
-The `CubeBlack-solo` build is identical to the CubeBlack build, but includes a large set of default parameters required by the Solo.
-
-- For use in ArduCopter 3.7 and higher. Not compatible with any previous versions of ArduCopter or with other vehicle types.
-- For data on the Hex CubeBlack flight controller, see the [Hex CubeBlack hwdef readme](https://github.com/ArduPilot/ardupilot/blob/master/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack/README.md)
-- For the parameter list used by this build, see [Tools/Fram_params/Solo_Copter-3.7_BlackCube.param](https://github.com/ArduPilot/ardupilot/blob/master/Tools/Frame_params/Solo_Copter-3.7_BlackCube.param)
-
-### Using this build in waf
-
-- `./waf configure --board CubeBlack-solo`
-- `./waf copter`
-- The completed firmware binary will be located in `/ardupilot/build/CubeBlack-solo/bin/arducopter.apj`
diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/README.md b/libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/README.md
new file mode 100644
index 0000000000..d46b2d500b
--- /dev/null
+++ b/libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/README.md
@@ -0,0 +1,11 @@
+# CubeSolo variant of the FMUv3
+
+The `CubeSolo` build is based on FMUv3, but includes a large set of default parameters required by the Solo.  Among many other things, this does include the slew rate limiting for protecting the Solo's ESCs.
+
+For the parameter list used by this build, see [Tools/Fram_params/Solo_Copter-3.7_BlackCube.param](https://github.com/ArduPilot/ardupilot/blob/master/Tools/Frame_params/Solo_Copter-3.7_BlackCube.param)
+
+### Using this build in waf
+
+- `./waf configure --board CubeSolo`
+- `./waf copter`
+- The completed firmware binary will be located in `/ardupilot/build/CubeSolo/bin/arducopter.apj`
diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/hwdef-bl.dat b/libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/hwdef-bl.dat
similarity index 100%
rename from libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/hwdef-bl.dat
rename to libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/hwdef-bl.dat
diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/hwdef.dat
similarity index 75%
rename from libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/hwdef.dat
rename to libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/hwdef.dat
index 6ad24fc01a..4a6ed7ca63 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/CubeBlack-solo/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/CubeSolo/hwdef.dat
@@ -3,7 +3,12 @@
 # this is based on the CubeBlack hwdef, with Solo's required parameter defaults
 # do not use this hwdef with any configuration other than a 3DR Solo with a stock or black cube running Copter 3.7.
 
-include ../CubeBlack/hwdef.dat
+include ../fmuv3/hwdef.dat
+
+env OPTIMIZE -O3
+
+SPIDEV icm20948_ext   SPI4 DEVID1  MPU_EXT_CS   MODE3  4*MHZ  8*MHZ
+SPIDEV icm20602_ext   SPI4 DEVID3  GYRO_EXT_CS  MODE3  4*MHZ  8*MHZ
 
 # pull Solo's default parameters from /Tools/Frame_params
 # these are parameters the Solo requires for proper operation that are differnet from the 3.7 standard defaults.