diff --git a/src/minimodem.1.in b/src/minimodem.1.in
index dc4f6b0..c95a0ee 100644
--- a/src/minimodem.1.in
+++ b/src/minimodem.1.in
@@ -31,7 +31,7 @@ is a command-line program which decodes (or generates) audio
 modem tones at any specified baud rate, using various framing protocols.
 It acts a general-purpose software FSK modem, and includes support for
 various standard FSK protocols such as Bell103, Bell202, RTTY, NOAA SAME,
-and Caller-ID.
+TTY/TDD, and Caller-ID.
 .PP
 .B Minimodem
 can play and capture audio modem tones in real-time via the system
@@ -67,6 +67,9 @@ default mark and space tone frequencies.
 .B    rtty
 : RTTY 45.45 bps \-\-baudot \-\-stopbits 1.5
 .TP
+.B    tdd
+: TTY/TDD 45.45 bps \-\-baudot \-\-stopbits 2.0
+.TP
 .B    same
 : SAME 520.83 bps \-\-startbits 0 \-\-stopbits 0 \-\-sync-byte 0xAB
 .br
diff --git a/tests/81-tdd.test b/tests/81-tdd.test
new file mode 100755
index 0000000..a55a2ac
--- /dev/null
+++ b/tests/81-tdd.test
@@ -0,0 +1 @@
+exec ./self-test testdata-baudot.txt tdd