1 files changed, 52 insertions, 0 deletions
diff --git a/stacks/tncs/tnc2c-chat.sh b/stacks/tncs/tnc2c-chat.sh
new file mode 100755
index 0000000..9323b5e
--- /dev/null
+++ b/stacks/tncs/tnc2c-chat.sh
@@ -0,0 +1,52 @@
+#!/bin/bash
+# Quick TNC2C terminal check on /dev/ttyS4 (no RF required).
+# WARNING: kiss on / MONitor can KEY PTT and transmit on the radio!
+# For passive RX only use: ./tnc2c-listen.sh
+# Usage: ./tnc2c-chat.sh [baud] [line]
+#   line: 7e1 | 8n1   (default from $TNC2C_LINE or 9600/7e1)
+
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "$0")" && pwd)"
+# shellcheck source=/dev/null
+[[ -f "$ROOT/tnc2c-serial.env" ]] && source "$ROOT/tnc2c-serial.env"
+
+DEV="${TNC2C_DEV:-/dev/ttyS4}"
+BAUD="${1:-${TNC2C_BAUD:-19200}}"
+LINE="${2:-${TNC2C_LINE:-7e1}}"
+
+case "$LINE" in
+7e1|7E1) STTY="cs7 parenb -cstopb" ;;
+8n1|8N1) STTY="cs8 -parenb -cstopb" ;;
+*) echo "Unknown line format: $LINE (use 7e1 or 8n1)" >&2; exit 1 ;;
+esac
+
+if [[ ! -r "$DEV" || ! -w "$DEV" ]]; then
+    echo "Cannot access $DEV (dialout group?)" >&2
+    exit 1
+fi
+
+echo "TNC2C chat: $DEV @ ${BAUD} ${LINE}"
+stty -F "$DEV" "$BAUD" $STTY raw -echo -icanon min 0 time 10
+
+exec 3<>"$DEV"
+
+printf '\r' >&3
+sleep 0.5
+timeout 2 cat <&3 | xxd -g1 | head -8 || true
+
+# Do NOT send kiss on — keys PTT. Only safe host echo probes:
+for cmd in '' INFO HELP; do
+    echo "--- $cmd ---"
+    if [[ -n "$cmd" ]]; then
+        printf '%s\r' "$cmd" >&3
+    else
+        printf '\r' >&3
+    fi
+    sleep 1
+    timeout 4 cat <&3 | tee /tmp/tnc2c-last.bin | xxd -g1 | head -12
+    strings -n 3 /tmp/tnc2c-last.bin || true
+done
+
+exec 3<&-
+exec 3>&-