1 files changed, 62 insertions, 0 deletions
diff --git a/stacks/tncs/tnc2c-check.sh b/stacks/tncs/tnc2c-check.sh
new file mode 100755
index 0000000..c0ab705
--- /dev/null
+++ b/stacks/tncs/tnc2c-check.sh
@@ -0,0 +1,62 @@
+#!/bin/bash
+# Preflight: HyBBX off? handshake OK? quick echo on TNC2C.
+# Usage: ./tnc2c-check.sh [device]
+
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "$0")" && pwd)"
+# shellcheck source=/dev/null
+[[ -f "$ROOT/tnc2c-serial.env" ]] && source "$ROOT/tnc2c-serial.env"
+
+DEV="${1:-${TNC2C_DEV:-/dev/ttyS4}}"
+BAUD="${TNC2C_BAUD:-19200}"
+LINE="${TNC2C_LINE:-7e1}"
+
+echo "=== TNC2C check: $DEV (${BAUD} ${LINE}) ==="
+
+if pgrep -x hybbx >/dev/null 2>&1; then
+    echo "WARN: hybbx is running ($(pgrep -x hybbx | tr '\n' ' ')) - port may be in use"
+fi
+
+if fuser -s "$DEV" 2>/dev/null; then
+    echo "WARN: $DEV in use:"
+    fuser -v "$DEV" 2>&1 || true
+else
+    echo "OK: $DEV not in use"
+fi
+
+if [[ ! -r "$DEV" || ! -w "$DEV" ]]; then
+    echo "FAIL: no access to $DEV (dialout group?)" >&2
+    exit 1
+fi
+
+case "$LINE" in
+7e1|7E1) STTY="cs7 parenb -cstopb" ;;
+8n1|8N1) STTY="cs8 -parenb -cstopb" ;;
+*) echo "Unknown line: $LINE" >&2; exit 1 ;;
+esac
+
+stty -F "$DEV" "$BAUD" $STTY raw -echo min 0 time 5
+
+python3 <<PY
+import fcntl, os, struct, time
+
+TIOCMGET = 0x5415
+fd = os.open("$DEV", os.O_RDWR | os.O_NOCTTY)
+flags = struct.unpack("I", fcntl.ioctl(fd, TIOCMGET, struct.pack("I", 0)))[0]
+names = [(0x004, "RTS"), (0x008, "CTS"), (0x002, "DTR"), (0x100, "DSR")]
+for bit, name in names:
+    print(f"  {name}={'1' if flags & bit else '0'}")
+os.write(fd, b"INFO\r")
+time.sleep(0.8)
+data = os.read(fd, 512)
+os.close(fd)
+print(f"  RX {len(data)} bytes:", data[:80])
+PY
+
+if [[ -x "$ROOT/tnc2c-probe" ]]; then
+    echo "--- tnc2c-probe (single port) ---"
+    "$ROOT/tnc2c-probe" "$DEV" 2>&1 | tail -20
+fi
+
+echo "=== done ==="