diff --git a/libraries/SITL/SIM_SerialDevice.cpp b/libraries/SITL/SIM_SerialDevice.cpp
new file mode 100644
index 0000000000..e2345b84ce
--- /dev/null
+++ b/libraries/SITL/SIM_SerialDevice.cpp
@@ -0,0 +1,54 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+/*
+  base class for serially-attached simulated devices
+*/
+
+#include "SIM_SerialDevice.h"
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+using namespace SITL;
+
+SerialDevice::SerialDevice()
+{
+    int tmp[2];
+    if (pipe(tmp) == -1) {
+        AP_HAL::panic("pipe() failed");
+    }
+    fd_my_end    = tmp[1];
+    fd_their_end = tmp[0];
+
+    // close file descriptors on exec:
+    fcntl(fd_my_end, F_SETFD, FD_CLOEXEC);
+    fcntl(fd_their_end, F_SETFD, FD_CLOEXEC);
+
+    // make sure we don't screw the simulation up by blocking:
+    fcntl(fd_my_end, F_SETFL, fcntl(fd_my_end, F_GETFL, 0) | O_NONBLOCK);
+    fcntl(fd_their_end, F_SETFL, fcntl(fd_their_end, F_GETFL, 0) | O_NONBLOCK);
+}
+
+bool SerialDevice::init_sitl_pointer()
+{
+    if (_sitl == nullptr) {
+        _sitl = AP::sitl();
+        if (_sitl == nullptr) {
+            return false;
+        }
+    }
+    return true;
+}
+
diff --git a/libraries/SITL/SIM_SerialDevice.h b/libraries/SITL/SIM_SerialDevice.h
new file mode 100644
index 0000000000..1be2933732
--- /dev/null
+++ b/libraries/SITL/SIM_SerialDevice.h
@@ -0,0 +1,46 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+/*
+  base class for serially-attached simulated devices
+*/
+
+#pragma once
+
+#include <SITL/SITL.h>
+
+#include <AP_HAL/utility/RingBuffer.h>
+
+namespace SITL {
+
+class SerialDevice {
+public:
+
+    SerialDevice();
+
+    // return fd on which data from the device can be read, and data
+    // to the device can be written
+    int fd() { return fd_their_end; }
+
+protected:
+
+    SITL *_sitl;
+
+    int fd_their_end;
+    int fd_my_end;
+
+    bool init_sitl_pointer();
+};
+
+}
diff --git a/libraries/SITL/SIM_Vicon.cpp b/libraries/SITL/SIM_Vicon.cpp
index bc832bd8da..a0f7b78830 100644
--- a/libraries/SITL/SIM_Vicon.cpp
+++ b/libraries/SITL/SIM_Vicon.cpp
@@ -29,23 +29,9 @@ using namespace SITL;
 #define USE_VISION_POSITION_ESTIMATE 1
 
 
-Vicon::Vicon()
+Vicon::Vicon() :
+    SerialDevice::SerialDevice()
 {
-    int tmp[2];
-    if (pipe(tmp) == -1) {
-        AP_HAL::panic("pipe() failed");
-    }
-    fd_my_end    = tmp[1];
-    fd_their_end = tmp[0];
-
-    // close file descriptors on exec:
-    fcntl(fd_my_end, F_SETFD, FD_CLOEXEC);
-    fcntl(fd_their_end, F_SETFD, FD_CLOEXEC);
-
-    // make sure we don't screw the simulation up by blocking:
-    fcntl(fd_my_end, F_SETFL, fcntl(fd_my_end, F_GETFL, 0) | O_NONBLOCK);
-    fcntl(fd_their_end, F_SETFL, fcntl(fd_their_end, F_GETFL, 0) | O_NONBLOCK);
-
     if (!valid_channel(mavlink_ch)) {
         AP_HAL::panic("Invalid mavlink channel");
     }
@@ -142,17 +128,6 @@ void Vicon::update_vicon_position_estimate(const Location &loc,
     time_send_us = now_us + delay_ms * 1000UL;
 }
 
-bool Vicon::init_sitl_pointer()
-{
-    if (_sitl == nullptr) {
-        _sitl = AP::sitl();
-        if (_sitl == nullptr) {
-            return false;
-        }
-    }
-    return true;
-}
-
 /*
   update vicon sensor state
  */
diff --git a/libraries/SITL/SIM_Vicon.h b/libraries/SITL/SIM_Vicon.h
index 2672dc84b1..e114df1e6f 100644
--- a/libraries/SITL/SIM_Vicon.h
+++ b/libraries/SITL/SIM_Vicon.h
@@ -24,9 +24,11 @@
 
 #include <AP_HAL/utility/RingBuffer.h>
 
+#include "SIM_SerialDevice.h"
+
 namespace SITL {
 
-class Vicon {
+class Vicon : public SerialDevice {
 public:
 
     Vicon();
@@ -34,14 +36,8 @@ public:
     // update state
     void update(const Location &loc, const Vector3f &position, const Quaternion &attitude);
 
-    // return fd on which data from the device can be read, and data
-    // to the device can be written
-    int fd() { return fd_their_end; }
-
 private:
 
-    SITL *_sitl;
-
     // TODO: make these parameters:
     const uint8_t system_id = 17;
     const uint8_t component_id = 18;
@@ -49,9 +45,6 @@ private:
     // we share channels with the ArduPilot binary!
     const mavlink_channel_t mavlink_ch = (mavlink_channel_t)(MAVLINK_COMM_0+5);
 
-    int fd_their_end;
-    int fd_my_end;
-
     uint64_t last_observation_usec;
     uint64_t time_send_us;
     uint64_t time_offset_us;
@@ -69,8 +62,6 @@ private:
 
     void maybe_send_heartbeat();
     uint32_t last_heartbeat_ms;
-
-    bool init_sitl_pointer();
 };
 
 }