diff --git a/ports/stm32/README.md b/ports/stm32/README.md
index f2fdb4dd3..6b5f096d7 100644
--- a/ports/stm32/README.md
+++ b/ports/stm32/README.md
@@ -2,11 +2,13 @@ MicroPython port to STM32 MCUs
 ==============================
 
 This directory contains the port of MicroPython to ST's line of STM32
-microcontrollers.  Supported MCU series are: STM32F0, STM32F4, STM32F7 and
-STM32L4.  Parts of the code here utilise the STM32Cube HAL library.
+microcontrollers.  Supported MCU series are: STM32F0, STM32F4, STM32F7,
+STM32H7, STM32L0, STM32L4 and STM32WB.  Parts of the code here utilise the
+STM32Cube HAL library.
 
 The officially supported boards are the line of pyboards: PYBv1.0 and PYBv1.1
-(both with STM32F405), and PYBLITEv1.0 (with STM32F411).  See
+(both with STM32F405), PYBLITEv1.0 (with STM32F411) and PYBD-SFx (with
+STM32F7xx MCUs).  See
 [micropython.org/pyboard](http://www.micropython.org/pyboard/) for further
 details.
 
@@ -40,18 +42,31 @@ see [here](https://launchpad.net/gcc-arm-embedded) for the main GCC ARM
 Embedded page.  The compiler can be changed using the `CROSS_COMPILE` variable
 when invoking `make`.
 
-First the submodules must be obtained using:
+Next, the board to build must be selected.  The default board is PYBV10 but any
+of the names of the subdirectories in the `boards/` directory is a valid board.
+The board name must be passed as the argument to `BOARD=` when invoking `make`.
 
-    $ make submodules
+All boards require certain submodules to be obtained before they can be built.
+The correct set of submodules can be initialised using (with `PYBV11` as an
+example of the selected board):
 
-Then to build for a given board, run:
+    $ make BOARD=PYBV11 submodules
+
+Then to build the board's firmware run:
 
     $ make BOARD=PYBV11
 
-The default board is PYBV10 but any of the names of the subdirectories in the
-`boards/` directory can be passed as the argument to `BOARD=`.  The above command
-should produce binary images in the `build-PYBV11/` subdirectory (or the
-equivalent directory for the board specified).
+The above command should produce binary images in the `build-PYBV11/`
+subdirectory (or the equivalent directory for the board specified).
+
+Note that some boards require the mboot bootloader to be built and deployed
+before flashing the main firmware.  For such boards an information message
+about this will be printed at the end of the main firmware build.  Mboot
+can be built via:
+
+    $ make -C mboot BOARD=STM32F769DISC
+
+For more information about mboot see mboot/README.md.
 
 
 ### Flashing the Firmware using DFU mode
@@ -140,6 +155,11 @@ Accessing the board
 -------------------
 
 Once built and deployed, access the MicroPython REPL (the Python prompt) via USB
-serial or UART, depending on the board.  For the pyboard you can try:
+serial or UART, depending on the board.  There are many ways to do this, one of
+which is via `mpremote` (install it using `pip install mpremote`):
+
+    $ mpremote
+
+Other options are `picocom` and `screen`, for example:
 
     $ picocom /dev/ttyACM0