From 5627222f4aa6bb1233721d246756bb5c3efb962b Mon Sep 17 00:00:00 2001
From: Jeremy Janella <jeremyjanell@gmail.com>
Date: Sat, 15 Aug 2026 18:25:35 -0400
Subject: [PATCH] docs: updated readme

---
 README.md | 102 +++++++++++++++++++-----------------------------------
 1 file changed, 35 insertions(+), 67 deletions(-)

diff --git a/README.md b/README.md
index a9b736f..6bf3f64 100644
--- a/README.md
+++ b/README.md
@@ -112,28 +112,17 @@ int main() {
 }
 ```
 
+Also, create an overlay for the firmware being executed in place. This is so the code jumps to addresses in the right block. Create `zephyr/samples/basic/blinkyslow/boards/nucleo_g431rb.overlay`
 
-
-## Build the blinkys
-
-The west build `-DSB_CONFIG_BOOTLOADER_MCUBOOT=y` flag enables MCUboot on the blinkys.
-
-```sh
-west build -p always -b nucleo_g431rb zephyr/samples/basic/blinky -d build/blinky --sysbuild -- -DSB_CONFIG_BOOTLOADER_MCUBOOT=y #-CONFIG_MCUBOOT_SERIAL_DIRECT_IMAGE_UPLOAD=y
-
-west build -p always -b nucleo_g431rb zephyr/samples/basic/blinkyslow -d build/blinkyslow --sysbuild -- -DSB_CONFIG_BOOTLOADER_MCUBOOT=y
+```
+/ {
+	chosen {
+		zephyr,code-partition = &slot1_partition;
+	};
+};
 ```
 
 
-## Flash the blinkys
-```sh
-pyocd flash -t stm32g431rbtx build
-/blinky/mcuboot/zephyr/zephyr.bin
-
-pyocd flash -t stm32g431rbtx --base-address 0x0000C000 build/blinky/blinky/zephyr/zephyr.bin
-```
-
-(blinkyslow is a clone of blinky with a different frequency)
 
 
 ## Set up crypto
@@ -143,28 +132,6 @@ python bootloader/mcuboot/scripts/imgtool.py keygen -k private.pem -t rsa-2048
 openssl rsa -in private.pem -pubout > public.pem
 ```
 
-## Sign the blinkys
-```sh
-python bootloader/mcuboot/scripts/imgtool.py sign \
-    --key private.pem \
-    --header-size 0x200 \
-    --pad-header \
-    --align 8 \
-    --version 1.2 \
-    --slot-size 0x8000 \
-    build/blinky/zephyr/zephyr.bin \
-    blinky-signed.bin
-
-python bootloader/mcuboot/scripts/imgtool.py sign \
-    --key private.pem \
-    --header-size 0x200 \
-    --pad-header \
-    --align 8 \
-    --version 1.2 \
-    --slot-size 0x8000 \
-    build/blinkyslow/zephyr/zephyr.bin \
-    blinkyslow-signed.bin
-```
 
 
 
@@ -178,6 +145,32 @@ west build -p always -b nucleo_g431rb -d build_fast zephyr/samples/basic/blinky
 west build -p always -b nucleo_g431rb -d build_slow zephyr/samples/basic/blinkyslow
 ```
 
+
+## Sign the firmware
+```sh
+python bootloader/mcuboot/scripts/imgtool.py sign \
+    --key private.pem \
+    --header-size 0x200 \
+    --pad-header \
+    --align 8 \
+	--pad \
+    --version 1.2 \
+    --slot-size 0xA000 \
+    build_fast/zephyr/zephyr.bin \
+    blinky-signed.bin
+
+python bootloader/mcuboot/scripts/imgtool.py sign \
+    --key private.pem \
+    --header-size 0x200 \
+    --pad-header \
+    --align 8 \
+	--pad \
+    --version 1.2 \
+    --slot-size 0xA000 \
+    build_slow/zephyr/zephyr.bin \
+    blinkyslow-signed.bin
+```
+
 ## Flash the firmware
 
 `su root` allows flashing to usb devices, run  `nix develop` again if using it.
@@ -185,34 +178,9 @@ west build -p always -b nucleo_g431rb -d build_slow zephyr/samples/basic/blinkys
 `flash0@0x08000000` in `zephyr/dts/arm/st/g4/stm32g4.dtsi`
 ```sh
 pyocd flash -t stm32g431rbtx build_mcuboot/zephyr/zephyr.hex
-
-pyocd flash -t stm32g431rbtx --base-address 0x0800C000 build_fast/zephyr/zephyr.bin
-
-pyocd flash -t stm32g431rbtx --base-address 0x08014000 build_slow/zephyr/zephyr.bin
+pyocd flash -t stm32g431rbtx --base-address 0x0800C000 blinky-signed.bin
+pyocd flash -t stm32g431rbtx --base-address 0x08016000 blinkyslow-signed.bin
 ```
 
 
 
-
-
-<!-- # Add the key file path to the KConfig https://docs.zephyrproject.org/latest/build/kconfig/setting.html
-echo "
-
-# Set the key file
-CONFIG_BOOT_SIGNATURE_KEY_FILE=public.pem" >> "./zephyr/boards/st/nucleo_g431rb/nucleo_g431rb_defconfig" -->
-
-
-
-<!-- west build -p always -b nucleo_g431rb bootloader/mcuboot/boot/zephyr -d build/mcuboot -- -DEXTRA_CONF_FILE=mcuboot-nucleo-g431rb.conf
-west flash -d build/mcuboot --runner pyocd # (as root, with nix develop)
-
-cd zephyr
-# Package 1
-west build -p always -b nucleo_g431rb samples/basic/blinky -d build/app -- -DCONFIG_BOOTLOADER_MCUBOOT=y -DCONFIG_MCUBOOT_GENERATE_UNSIGNED_IMAGE=y
-west flash -d build/app --runner pyocd  # (as root, with nix develop)
-
-# Package 2
-west build -p always -b nucleo_g431rb samples/basic/blinkyslow -d build/blinkyslow -- -DCONFIG_BOOTLOADER_MCUBOOT=y -DCONFIG_MCUBOOT_GENERATE_UNSIGNED_IMAGE=y
-pyocd flash --target stm32g431rbtx --base-address 0x08014800  build/blinkyslow/zephyr/zephyr.signed.hex
-``` -->
-