diff --git a/doc/user_manual.md b/doc/user_manual.md
index a6ebc3a..ce47936 100644
--- a/doc/user_manual.md
+++ b/doc/user_manual.md
@@ -351,9 +351,11 @@ In the response string, such data elements are separated by space characters.
 | `AIN:TRIGGER:EXT:CHANNEL` | External trigger channel. |
 | `AIN:TRIGGER:EXT:EDGE`    | External trigger edge. |
 | `AIN:ACQUIRE:ENABLE`      | Enable analog acquisition. |
+| `AIN:CLEAR`               | Clear buffer and drop data connection. |
 | `TT:SAMPLE?`              | Digital input state. |
 | `TT:EVENT:MASK`           | Timetagger event mask. |
 | `TT:MARK`                 | Emit timetagger marker. |
+| `TT:CLEAR`                | Clear buffer and drop data connection. |
 | `TEMP:FPGA?`              | FPGA temperature. |
 | `IPCFG[:SAVED]`           | IP address configuration. |
 | `HALT`                    | Shut down system. |
@@ -626,6 +628,17 @@ When disabled, all triggers are ignored and any ongoing analog acquisition stops
 Query: `AIN:ACQUIRE:ENABLE?` <br>
 Response: either `0` or `1`.
 
+### `AIN:CLEAR`
+
+Command: `AIN:CLEAR`
+
+This command clears internal buffers holding analog acquisition data.
+It also drops the current data connection to port 5001, if any.
+
+Clients should send this command just before connecting to the analog
+sample data port and enabling analog data acquisition.
+This prevents the transmission of stale data from a previous run.
+
 ### `TT:SAMPLE?`
 
 Query: `TT:SAMPLE?` <br>
@@ -662,6 +675,17 @@ Command: `TT:MARK`
 
 This command emits a marker record in the timetagger event stream.
 
+### `TT:CLEAR`
+
+Command: `TT:CLEAR`
+
+This command clears internal buffers holding timetagger data.
+It also drops the current data connection to port 5002, if any.
+
+Clients should send this command just before connecting to the timetagger
+data port and enabling timetagger events.
+This prevents the transmission of stale data from a previous run.
+
 ### `TEMP:FPGA?`
 
 Query: `TEMP:FPGA?` <br>