diff --git a/build/misc.tcl b/build/misc.tcl
index 97cdb370..c44f4fbd 100644
--- a/build/misc.tcl
+++ b/build/misc.tcl
@@ -1111,6 +1111,22 @@ respond "M IML" "\r"
 respond ":PDUMP" "games; ts maze\r"
 respond "*" ":kill\r"
 
+# KLH's Knight TV clock.
+respond "*" ":midas klh; ts tinyw_klh; clock\r"
+respond "=" "1\r"
+respond "=" "1\r"
+expect ":KILL"
+respond "*" ":midas klh; ts bigw_klh; clock\r"
+respond "=" "1\r"
+respond "=" "0\r"
+respond "=" "0\r"
+expect ":KILL"
+respond "*" ":midas klh; ts digiw_klh; clock\r"
+respond "=" "1\r"
+respond "=" "0\r"
+respond "=" "1\r"
+expect ":KILL"
+
 # The old CLIB has a UFA instruction which doesn't work on a KS10.
 # Patch out the call to FIXIFY.
 respond "*" ":job cc\r"
diff --git a/doc/programs.md b/doc/programs.md
index 5261a20b..4e5f1933 100644
--- a/doc/programs.md
+++ b/doc/programs.md
@@ -47,6 +47,7 @@
 - CHESS2, Alan Baisley's Tech II chess program.
 - CHTN/CFTP, Chaosnet TELNET and FTP support.
 - CKR, Alan Baisley's checkers program.
+- CLOCK, analogue, small, or digital clock.
 - CLOGO, Logo programming language.
 - COMBAT, submit jobs to the Muddle compiler.
 - COMIFY, convert HEX to COM format.