Test with modem connected

modem/modem_dtmf.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env python3
+
+import argparse
+import sys
+import time
+import serial
+
+def read_response(port: serial.Serial, timeout_s: float) -> list[str]:
+    deadline = time.monotonic() + timeout_s
+    lines: list[str] = []
+
+    while time.monotonic() < deadline:
+        raw = port.readline()
+        if not raw:
+            continue
+
+        line = raw.decode(errors="replace").strip()
+        if not line:
+            continue
+
+        lines.append(line)
+        if line in {"OK", "ERROR"}:
+            break
+
+    return lines
+
+def send_at(port: serial.Serial, command: str, timeout_s: float) -> tuple[bool, list[str]]:
+    port.write((command + "\r").encode())
+    port.flush()
+    lines = read_response(port, timeout_s)
+
+    ok = any(line == "OK" for line in lines)
+    err = any(line == "ERROR" for line in lines)
+    return ok and not err, lines
+
+def send_and_log(port: serial.Serial, command: str, timeout_s: float) -> tuple[bool, list[str]]:
+    ok, lines = send_at(port, command, timeout_s)
+    print(f"> {command}")
+    for line in lines:
+        print(f"< {line}")
+    return ok, lines
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description="Control an AT modem and send DTMF tones")
+    parser.add_argument("device", help="Serial device path, e.g. /dev/ttyACM0")
+    parser.add_argument("--baud", type=int, default=115200, help="Serial baudrate (default: 115200)")
+    parser.add_argument("--timeout", type=float, default=2.0, help="AT command timeout seconds")
+    args = parser.parse_args()
+
+    try:
+        with serial.Serial(args.device, args.baud, timeout=0.2, write_timeout=1.0) as port:
+            port.reset_input_buffer()
+            port.reset_output_buffer()
+
+            # Inicialise
+
+            for cmd in ("AT", "ATZ0", "ATE1", "ATX0"):
+                ok, lines = send_and_log(port, cmd, args.timeout)
+                if not ok:
+                    print(f"Modem did not accept {cmd}", file=sys.stderr)
+                    return 1
+
+            send_and_log(port, "ATS6=0", args.timeout) # Set wait for dial tone time to 0
+            send_and_log(port, "ATS11=2", args.timeout) # set tone length to 1 ms
+            send_and_log(port, "ATH1", args.timeout)
+            while True:
+                send_and_log(port, "ATDT0123456789;", args.timeout)
+            send_and_log(port, "ATH0", args.timeout)
+
+    except serial.SerialException as exc:
+        print(f"Serial error: {exc}", file=sys.stderr)
+        return 1
+
+    print("Done")
+    return 0
+
+if __name__ == "__main__":
+    raise SystemExit(main())