UA1ZBE Custom Firmware v1.0

Features:
- VFO mode with direct frequency input
- POCSAG decoder (512/1200 baud) with BCH(31,21) correction
- Full-screen Spectrum analyzer
- FM Radio receiver
- RSSI signal indicator overlay
- Custom boot splash (UA1ZBE / POCSAG pager / build date)

Architecture:
- app/mode.c — mode dispatcher (VFO/POCSAG/Spectrum/FM)
- app/boot_splash.c — 2-second boot splash
- app/pocsag/ — POCSAG decoder + BCH correction
- app/display_rssi.c — RSSI indicator
- main.c — entry point with custom init
- syscalls.c — bare-metal _sbrk stub

Build: arm-none-eabi-gcc -Os -flto -Wall -Werror -Wextra
Size: 57.9KB Flash / 3.6KB RAM

Controls:
- 0-9: Direct frequency input (VFO)
- SK2: POCSAG mode
- SK1: Spectrum analyzer
- 0: FM Radio
- EXIT: Return to VFO
- F/*: Toggle 512/1200 baud (in POCSAG)

win_make.bat

@@ -0,0 +1,62 @@
+
+@echo off
+
+
+
+
+:: Compile directly in windows without the need of a linux virtual machine:
+:: 
+:: 1. Download and install "gcc-arm-none-eabi-10.3-2021.10-win32.exe" from https://developer.arm.com/downloads/-/gnu-rm
+:: 2. Download and install "gnu_make-3.81.exe" from https://gnuwin32.sourceforge.net/packages/make.htm
+::
+:: 3. You may (or may not) need to manualy add a path to you OS environment PATH, ie ..
+::    C:\Program Files (x86)\GNU Arm Embedded Toolchain\10 2021.10\bin
+::
+:: 4. You may (or may not) need to reboot windows after installing the above
+:: 
+:: You can then run this bat from the directory you saved the firmware source code too.
+
+
+
+:: You may need to edit/change these three paths to suit your setup
+::
+:: Temporarily add the compiler and make program directories to the system PATH ..
+::
+@set PATH="C:\Program Files (x86)\GNU Arm Embedded Toolchain\10 2021.10\bin";%PATH%
+@set PATH="C:\Program Files (x86)\GNU Arm Embedded Toolchain\10 2021.10\arm-none-eabi\bin";%PATH%
+@set PATH="C:\Program Files (x86)\GnuWin32\bin\";%PATH%
+
+:: Do the compile
+::
+make clean
+make
+
+
+:: If you have python installed, you can create a 'packed' .bin from the compiled firmware.bin file.
+:: The Quansheng windows upload-to-radio program requires a 'packed' .bin file.
+::
+:: if you don't have python installed, then you can still upload the standard unpacked firmware.bin
+:: file another way ...
+::
+:: I wrote a GUI version of k5prog to do this easily in windows ..
+::    https://github.com/OneOfEleven/k5prog-win
+
+
+
+:: One of these two lines simply install the required python module if you want to create the packed
+:: firmware bin file, either only needs running once, ever.
+::
+::python  -m pip install --upgrade pip crcmod
+::python3 -m pip install --upgrade pip crcmod
+
+
+
+:: show the compiled .bin file size
+::
+::arm-none-eabi-size firmware
+
+
+
+
+pause
+@echo on