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/RTX/LIB/fetch_libs.sh

@@ -0,0 +1,80 @@
+#!/bin/bash
+
+VERSION=4.82.0
+if [ -z "$JENKINS_FAMILY_ENV" ]; then
+    ARTIFACTORY_URL=https://artifactory.eu02.arm.com:443/artifactory/mcu.promoted
+else
+    ARTIFACTORY_URL=https://eu-west-1.artifactory.aws.arm.com:443/artifactory/mcu.promoted
+fi
+
+if [ -z "$ARTIFACTORY_API_KEY" ]; then
+  echo "Please set your Artifactory in ARTIFACTORY_API_KEY"
+  echo ""
+  echo "1. Browse to $(dirname $(dirname $ARTIFACTORY_URL))/ui/admin/artifactory/user_profile"
+  echo "2. Copy the API Key"
+  echo "3. Add 'export ARTIFACTORY_API_KEY=\"<API Key>\"' to ~/.bashrc"
+  exit 1
+fi
+
+set -o pipefail
+
+function usage {
+  echo "$(basename $0) [-h|--help] [-f|--force]"
+  echo ""
+  echo "Arguments:"
+  echo "  -h|--help   Print this usage message and exit."
+  echo "  -f|--force  Force (re)download."
+  echo ""
+  echo "Environment:"
+  echo " curl"
+  echo " sha256sum"
+  echo ""
+}
+
+POSITIONAL=()
+while [[ $# -gt 0 ]]
+do
+  key="$1"
+
+  case $key in
+    '-h'|'--help')
+      usage
+      exit 1
+    ;;
+    '-f'|'--force')
+      FORCE=1
+    ;;
+    *)    # unknown option
+      POSITIONAL+=("$1") # save it in an array for later
+    ;;
+  esac
+  shift # past argument
+done
+set -- "${POSITIONAL[@]}" # restore positional parameters
+
+pushd $(dirname $0) > /dev/null
+
+ARCHIVE_NAME="RTX-${VERSION}.zip"
+ARCHIVE_URL="${ARTIFACTORY_URL}/CMSIS_5/Libraries/${ARCHIVE_NAME}"
+echo "Fetching ${ARCHIVE_URL}..."
+
+if [[ $FORCE == 1 ]]; then
+    rm ${ARCHIVE_NAME}
+fi
+
+if [[ -f ${ARCHIVE_NAME} ]]; then
+    sha256sum=$(curl -s -I -H "X-JFrog-Art-Api:${ARTIFACTORY_API_KEY}" "${ARCHIVE_URL}" | grep "X-Checksum-Sha256" | cut -d" " -f2)
+    if echo "${sha256sum} *${ARCHIVE_NAME}" | sha256sum -c --status; then
+        echo "Already up-to-date"
+    else
+        rm ${ARCHIVE_NAME}
+    fi
+fi
+
+if [[ ! -f ${ARCHIVE_NAME} ]]; then
+    curl -C - -H "X-JFrog-Art-Api:${ARTIFACTORY_API_KEY}" -O "${ARCHIVE_URL}"
+fi
+
+unzip -u ${ARCHIVE_NAME}
+
+exit 0