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)

external/CMSIS_5/CMSIS/RTOS/Template/CPP/RtosTimer.h

@@ -0,0 +1,49 @@
+/* Copyright (c) 2012 mbed.org */
+#ifndef TIMER_H
+#define TIMER_H 
+
+#include <stdint.h>
+#include "cmsis_os.h"
+
+namespace rtos {
+
+/*! The RtosTimer class allow creating and and controlling of timer functions in the system.
+ A timer function is called when a time period expires whereby both on-shot and
+ periodic timers are possible. A timer can be started, restarted, or stopped.
+
+ Timers are handled in the thread osTimerThread.
+ Callback functions run under control of this thread and may use CMSIS-RTOS API calls. 
+*/
+class RtosTimer {
+public:
+    /*! Create and Start timer.
+      \param   task      name of the timer call back function.
+      \param   type      osTimerOnce for one-shot or osTimerPeriodic for periodic behaviour. (default: osTimerPeriodic)
+      \param   argument  argument to the timer call back function. (default: NULL)
+    */
+    RtosTimer(void (*task)(void const *argument),
+          os_timer_type type=osTimerPeriodic,
+          void *argument=NULL);
+    
+    /*! Stop the timer.
+      \return  status code that indicates the execution status of the function. 
+    */
+    osStatus stop(void);
+    
+    /*! start a timer.
+      \param   millisec  time delay value of the timer.
+      \return  status code that indicates the execution status of the function. 
+    */
+    osStatus start(uint32_t millisec);
+
+private:
+    osTimerId _timer_id;
+    osTimerDef_t _timer;
+#ifdef CMSIS_OS_RTX
+    uint32_t _timer_data[5];
+#endif
+};
+
+}
+
+#endif