feat: MEMS microphone software handling for TX15 and TX16SMK3 (#7328)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

radio/src/cli.cpp

@@ -50,8 +50,10 @@
 #include <malloc.h>
 #include <new>
 #include <stdarg.h>
+#include <string.h>
 
 #include "lua/lua_states.h"
+#include "pdm_wav_recorder.h"
 
 #define CLI_COMMAND_MAX_ARGS           8
 #define CLI_COMMAND_MAX_LEN            256
@@ -262,6 +264,69 @@ int cliPlay(const char ** argv)
   return 0;
 }
 
+#if defined(PDM_CLOCK)
+// Record from the PDM microphone to a 16-bit mono WAV file. The actual
+// capture + resampling + WAV I/O lives in PdmWavRecorder so the same
+// pipeline is reused by the GUI recorder tool.
+int cliRecord(const char ** argv)
+{
+  if (!argv[1] || !argv[1][0]) {
+    cliSerialPrint("%s: missing filename", argv[0]);
+    return 0;
+  }
+
+  int seconds = 5;
+  if (argv[2] && argv[2][0]) {
+    if (toInt(argv, 2, &seconds) == 0 || seconds <= 0 || seconds > 600) {
+      cliSerialPrint("%s: Invalid duration \"%s\"", argv[0], argv[2]);
+      return 0;
+    }
+  }
+
+  char pathBuf[64];
+  const char* path = argv[1];
+  const size_t nameLen = strlen(argv[1]);
+  const bool hasExt =
+      nameLen >= 4 && strcasecmp(argv[1] + nameLen - 4, ".wav") == 0;
+  if (!hasExt) {
+    if (nameLen + 5 > sizeof(pathBuf)) {
+      cliSerialPrint("%s: path too long", argv[0]);
+      return 0;
+    }
+    memcpy(pathBuf, argv[1], nameLen);
+    memcpy(pathBuf + nameLen, ".wav", 5);
+    path = pathBuf;
+  }
+
+  const uint32_t totalSamples = PdmWavRecorder::DST_RATE * (uint32_t)seconds;
+  // Capture only runs while needed — bring the hardware up for this command.
+  pdmStart();
+  PdmWavRecorder rec;
+  FRESULT res = rec.start(path, (uint32_t)seconds);
+  if (res != FR_OK) {
+    pdmStop();
+    cliSerialPrint("%s: cannot open \"%s\" (err %u)", argv[0], path,
+                   (unsigned)res);
+    return 0;
+  }
+
+  cliSerialPrint("Recording %d s (%u samples @ %u Hz) to %s",
+                 seconds, (unsigned)totalSamples,
+                 (unsigned)PdmWavRecorder::DST_RATE, path);
+
+  while (rec.isRecording() && rec.getSamplesWritten() < totalSamples) {
+    sleep_ms(50);
+  }
+
+  rec.stop();
+  pdmStop();
+  cliSerialPrint("Recorded %u samples (%u bytes)",
+                 (unsigned)rec.getSamplesWritten(),
+                 (unsigned)rec.getBytesWritten());
+  return 0;
+}
+#endif // PDM_CLOCK
+
 int cliLs(const char ** argv)
 {
   FILINFO fno;
@@ -1787,6 +1852,9 @@ const CliCommand cliCommands[] = {
   { "readsd", cliReadSD, "<start sector> <sectors count> <read buffer size (sectors)>" },
   { "testsd", cliTestSD, "" },
   { "play", cliPlay, "<filename>" },
+#if defined(PDM_CLOCK)
+  { "rec", cliRecord, "<filename> [<seconds>]" },
+#endif
   { "reboot", cliReboot, "[wdt]" },
   { "set", cliSet, "<what> <value>" },
 #if defined(ENABLE_SERIAL_PASSTHROUGH)