diff --git a/libraries/AP_Scripting/drivers/mount-topotek-driver.lua b/libraries/AP_Scripting/drivers/mount-topotek-driver.lua
new file mode 100755
index 00000000000000..f4f10fd5b7ffc0
--- /dev/null
+++ b/libraries/AP_Scripting/drivers/mount-topotek-driver.lua
@@ -0,0 +1,833 @@
+-- mount-topotek-driver.lua: Topotek mount/gimbal driver
+
+--[[
+  How to use
+    Connect gimbal UART to one of the autopilot's serial ports
+    Set SERIALx_PROTOCOL = 28 (Scripting) where "x" corresponds to the serial port connected to the gimbal
+    Set SERIALx_BAUD = 115 (115200)
+    Set SCR_ENABLE = 1 to enable scripting and reboot the autopilot
+    Set MNT1_TYPE = 9 (Scripting) to enable the mount/gimbal scripting driver
+    Set CAM1_TYPE = 7 (Scripting) to enable the camera scripting driver
+    Set RCx_OPTION = 300 (Scripting1) to control which camera's picture-in-picture mode.
+    Set SCR_HEAP_SIZE = 120000
+    Copy this script to the autopilot's SD card in the APM/scripts directory and reboot the autopilot
+    Set MNT1_RC_RATE to 90 (deg/s) to control gimbal movement.
+    Optionally set TOPK_DEBUG = 1 or 2 to increase level of debug output to the GCS
+    Reboot the autopilot
+
+  Packet format
+  Field                 Index   Bytes       Description
+  -------------------------------------------------------------------------------------------
+  Frame Header          0       3           type of command
+  Address Bit           3       2           the source address comes first, and the destination address comes last
+  Data_Len              5       1           data length
+  Control Bit           6       1           r -> query w -> setup and control
+  Identification Bit    7       3           identification function
+  Data                  10      Data_Len
+  Check Bit                     2           the frame header is converted to HEX before reaching the check bit,
+                                            the sum is done, and the result is converted to ASC-II. Two bytes, the high one first
+
+--]]
+
+-- parameters
+local PARAM_TABLE_KEY = 138
+assert(param:add_table(PARAM_TABLE_KEY, "TOPK_", 1), "could not add param table")
+assert(param:add_param(PARAM_TABLE_KEY, 1, "DEBUG", 0), "could not add TOPK_DEBUG param")
+
+-- bind parameters to variables
+local MNT1_TYPE = Parameter("MNT1_TYPE")               -- should be 9:Scripting
+local CAM1_TYPE = Parameter("CAM1_TYPE")               -- should be 7:Scripting
+
+--[[
+  // @Param: TOPK_DEBUG
+  // @DisplayName: Topotek debug
+  // @Description: Topotek debug
+  // @Values: 0:Disabled, 1:Enabled, 2:Enabled including attitude reporting
+  // @User: Advanced
+--]]
+local TOPK_DEBUG = Parameter("TOPK_DEBUG")             -- debug level. 0:disabled 1:enabled 2:enabled with attitude reporting
+
+-- global definitions
+local CAM_PIP_RC_OPTION = 300                          -- rc channel option used to control which camera's picture-in-picture mode. RCx_OPTION = 300 (scripting1)
+local MAV_SEVERITY = {EMERGENCY=0, ALERT=1, CRITICAL=2, ERROR=3, WARNING=4, NOTICE=5, INFO=6, DEBUG=7}
+local INIT_INTERVAL_MS = 3000                          -- attempt to initialise the gimbal at this interval
+local UPDATE_INTERVAL_MS = 100                         -- update at 10hz
+local MOUNT_INSTANCE = 0                               -- always control the first mount/gimbal
+local CAMERA_INSTANCE = 0                              -- always use the first camera
+local ANGULAR_VELOCITY_CONVERSION = 1.220740379        -- gimbal angular velocity conversion ratio
+local TRACK_TOTAL_WIDTH  = 1920                        -- track the maximum width of the image range
+local TRACK_TOTAL_HEIGHT = 1080                        -- track the maximum height of the image range
+local TRACK_RANGE = 60                                 -- the size of the image at point tracking
+
+-- local variables and definitions
+local uart                                             -- uart object connected to mount
+local initialised = false                              -- true once connection to gimbal has been initialised
+local gimbal_stop_order_count = 0                      -- record the number of times the stop command is sent to the gimbal.
+local cam_pic_count = 0                                -- last picture count.  used to detect trigger pic
+local cam_rec_video = false                            -- last record video state.  used to detect record video
+local cam_zoom_type = 0                                -- last zoom type 1:Rate 2:Pct
+local cam_zoom_value = 0                               -- last zoom value.  If rate, zoom out = -1, hold = 0, zoom in = 1.  If Pct then value from 0 to 100
+local cam_focus_type = 0                               -- last focus type 1:Rate, 2:Pct, 4:Auto
+local cam_focus_value = 0                              -- last focus value.  If Rate then focus in = -1, focus hold = 0, focus out = 1
+local last_tracking_type = 0                           -- last recorded tracking type (0:None, 1:Point, 2:Rectangle)
+local last_tracking_p1x = 0                            -- last recorded tracking point1 (used for center or top-left)
+local last_tracking_p1y = 0                            -- last recorded tracking point1 (used for center or top-left)
+local last_tracking_p2x = 0                            -- last recorded tracking point2 (bottom-right)
+local last_tracking_p2y = 0                            -- last recorded tracking point2 (bottom-right)
+local cam_pip_status = 0                               -- last recorded picture-in-picture mode state will be switched to the next one if it is inconsistent with the current state.
+local gimbal_lock = false                              -- last recorded recorded lock mod. true indicates locked, false indicates followed
+local is_tracking = false                              -- last recorded gimbal tracking mode. true indicates currently tracking, false indicates tracking stopped.
+local SD_status = false                                -- last recorded status of the gimbal's SD card. true indicates normal status, false indicates abnormal status.
+local zoom_stop = false                                -- when the stop command for zoom is sent, this value will be true, allowing the stop command to be resent in the next loop.
+local focus_stop = false                               -- when the stop command for focus is sent, this value will be true, allowing the stop command to be resent in the next loop.
+local recv_msg_buff = {}                               -- data received from the gimbal.
+local send_count = 0                                   -- send data count to the gimbal to control the sending frequency.
+local char_map = {}                                    -- store the ASCII values corresponding to 1~9, A~F.
+local number_map = {}                                  -- store the hexadecimal values corresponding to 1~9, A~F, a~f.
+-- send hard coded message
+function send_msg(msg)
+
+  local send_msg = add_check(msg)
+  for i=1,#send_msg do
+    uart:write(send_msg[i])
+  end
+end
+
+-- calculate the checksum for the data to be sent.
+function send_calculate_crc(msg)
+  local crc = 0;
+  for i=1, #msg do
+    crc = crc + msg[i]
+  end
+  return crc & 0xFF
+end
+
+-- calculate the checksum for the data to be received.
+function recv_calculate_crc(msg)
+  local crc = 0;
+  for i=1, #msg - 2 do
+    crc = crc + msg[i]
+  end
+  return crc & 0xFF
+end
+
+-- add check
+function add_check(msg)
+  local crc = send_calculate_crc(msg)
+  local len = #msg
+  msg[len + 1] = char_map[(crc>>4) & 0x0F]
+  msg[len + 2] = char_map[(crc) & 0x0F]
+  return msg
+end
+
+
+-- send stop commands twice to prevent the gimbal from not receiving the command
+function repeat_stop_cmd()
+  if zoom_stop then
+    local zoom_stop_cmd = {35, 84, 80, 85, 77, 50, 119, 90, 77, 67, 48, 48}
+    send_msg(zoom_stop_cmd)                       -- zoom stop
+    zoom_stop = false
+  end
+
+  if focus_stop then
+    local focus_stop_cmd = {35, 84, 80, 85, 77, 50, 119, 70, 67, 67, 48, 48}
+    send_msg(focus_stop_cmd)                      -- focus stop
+    focus_stop = false
+  end
+end
+
+-- attitude information analysis of gimbal
+function gimbal_angle_analyse()
+
+  if #recv_msg_buff < 22 then
+    return
+  end
+
+  local yaw = number_map[recv_msg_buff[11]]<<12 | number_map[recv_msg_buff[12]]<<8 | number_map[recv_msg_buff[13]]<<4 | number_map[recv_msg_buff[14]]
+  local pitch = number_map[recv_msg_buff[15]]<<12 | number_map[recv_msg_buff[16]]<<8 | number_map[recv_msg_buff[17]]<<4 | number_map[recv_msg_buff[18]]
+  local roll = number_map[recv_msg_buff[19]]<<12 | number_map[recv_msg_buff[20]]<<8 | number_map[recv_msg_buff[21]]<<4 | number_map[recv_msg_buff[22]]
+
+  if yaw > 32767 then
+    yaw = yaw - 65536
+  end
+
+  if pitch > 32767 then
+    pitch = pitch - 65536
+  end
+
+  if roll > 32767 then
+    roll = roll - 65536
+  end
+
+  if 18000 < yaw then
+    yaw = yaw - 36000
+  elseif -18000 > yaw then
+    yaw = yaw + 36000
+  end
+
+  -- divide the data by 100 to obtain the actual value.
+  roll = roll / 100
+  pitch = pitch / 100
+  yaw = yaw / 100
+
+  if TOPK_DEBUG:get() > 1 then
+    gcs:send_text(MAV_SEVERITY.INFO, "Topotek: gimbal angle roll:"..roll.." pitch:"..pitch.." yaw:"..yaw)
+  end
+end
+
+-- gimbal video information analysis
+function gimbal_record_analyse()
+
+  if #recv_msg_buff < 12 then
+    return
+  end
+  if recv_msg_buff[11] == 49 or recv_msg_buff[12] == 49 then
+    gcs:send_text(MAV_SEVERITY.INFO, "Topotek: start recording")
+    return
+  end
+
+  gcs:send_text(MAV_SEVERITY.INFO, "Topotek: stop recording")
+end
+
+-- information analysis of gimbal storage card
+function gimbal_sdcard_analyse()
+
+  if #recv_msg_buff < 14 then
+    return
+  end
+  if recv_msg_buff[11] == 78 and recv_msg_buff[12] == 78 and recv_msg_buff[13] == 78 and recv_msg_buff[14] == 78 then
+    SD_status = false
+    return
+  end
+
+  SD_status = true
+end
+
+-- gimbal tracking information analysis
+function gimbal_track_analyse()
+
+  if #recv_msg_buff < 12 then
+    return
+  end
+  local track_status = recv_msg_buff[12];
+  if track_status == 48 then
+    gcs:send_text(MAV_SEVERITY.WARNING, "Topotek: trace exception")
+  elseif track_status == 49 then
+    gcs:send_text(MAV_SEVERITY.INFO, "Topotek: stop tracking")
+  else
+    gcs:send_text(MAV_SEVERITY.INFO, "Topotek: be tracking")
+  end
+end
+
+-- analyze the data information received
+function analyse_data()
+  if #recv_msg_buff > 10 then
+    local crc = recv_calculate_crc(recv_msg_buff)
+    if char_map[(crc>>4) & 0x0F] == recv_msg_buff[#recv_msg_buff - 1] and char_map[crc & 0x0F] == recv_msg_buff[#recv_msg_buff] then
+      if recv_msg_buff[8] == 71 and recv_msg_buff[9] == 65 and recv_msg_buff[10] == 67 then
+        gimbal_angle_analyse()
+      elseif recv_msg_buff[8] == 72 and recv_msg_buff[9] == 69 and recv_msg_buff[10] == 67 then
+        gimbal_record_analyse()
+      elseif recv_msg_buff[8] == 83 and recv_msg_buff[9] == 68 and recv_msg_buff[10] == 67 then
+        gimbal_sdcard_analyse()
+      elseif recv_msg_buff[8] == 84 and recv_msg_buff[9] == 82 and recv_msg_buff[10] == 67 then
+        gimbal_track_analyse()
+      end
+    end
+  end
+  recv_msg_buff = {}
+end
+
+-- reading incoming packets from gimbal
+function read_incoming_packets()
+  local n_bytes = uart:available()
+  if n_bytes <= 0 then
+    return
+  end
+
+  if n_bytes > 128 then
+    n_bytes = 128
+    while n_bytes > 0 do
+      n_bytes = n_bytes - 1
+      uart:read()
+    end
+    do return end
+  end
+
+  local recv_msg_len = 1
+  while n_bytes > 0 do
+    n_bytes = n_bytes - 1
+    local b = uart:read()
+    if b then
+      if #recv_msg_buff ~= 0 or b == 35 then
+        if #recv_msg_buff ~= 0 and b == 35 then
+          analyse_data()
+          recv_msg_len = 1;
+        end
+        recv_msg_buff[recv_msg_len] = b
+        recv_msg_len = recv_msg_len + 1
+      end
+    end
+  end
+
+  analyse_data()
+end
+
+-- send the angles for yaw and pitch.
+function set_yaw_pitch_angle(yaw_angle_hund, pitch_angle_hund, speed)
+  -- set gimbal yaw and pitch angle command
+  local set_yaw_pitch_angle_cmd = {35, 116, 112, 85, 71, 99, 119, 71, 65, 77}
+
+  set_yaw_pitch_angle_cmd[11] = char_map[(yaw_angle_hund>>12) & 0x0F]
+  set_yaw_pitch_angle_cmd[12] = char_map[(yaw_angle_hund>>8) & 0x0F]
+  set_yaw_pitch_angle_cmd[13] = char_map[(yaw_angle_hund>>4) & 0x0F]
+  set_yaw_pitch_angle_cmd[14] = char_map[(yaw_angle_hund) & 0x0F]
+
+  set_yaw_pitch_angle_cmd[15] = char_map[(speed>>4) & 0x0F]
+  set_yaw_pitch_angle_cmd[16] = char_map[(speed) & 0x0F]
+
+  set_yaw_pitch_angle_cmd[17] = char_map[(pitch_angle_hund>>12) & 0x0F]
+  set_yaw_pitch_angle_cmd[18] = char_map[(pitch_angle_hund>>8) & 0x0F]
+  set_yaw_pitch_angle_cmd[19] = char_map[(pitch_angle_hund>>4) & 0x0F]
+  set_yaw_pitch_angle_cmd[20] = char_map[(pitch_angle_hund) & 0x0F]
+
+  set_yaw_pitch_angle_cmd[21] = char_map[(speed>>4) & 0x0F]
+  set_yaw_pitch_angle_cmd[22] = char_map[(speed) & 0x0F]
+
+  send_msg(set_yaw_pitch_angle_cmd)
+end
+
+-- send the angles for roll
+function set_roll_angle(roll_angle_hund, speed)
+  -- set gimbal roll angle command
+  local set_roll_angle_cmd = {35, 116, 112, 85, 71, 54, 119, 71, 65, 82}
+
+  set_roll_angle_cmd[11] = char_map[(roll_angle_hund>>12) & 0x0F]
+  set_roll_angle_cmd[12] = char_map[(roll_angle_hund>>8) & 0x0F]
+  set_roll_angle_cmd[13] = char_map[(roll_angle_hund>>4) & 0x0F]
+  set_roll_angle_cmd[14] = char_map[(roll_angle_hund) & 0x0F]
+
+  set_roll_angle_cmd[15] = char_map[(speed>>4) & 0x0F]
+  set_roll_angle_cmd[16] = char_map[(speed) & 0x0F]
+
+  send_msg(set_roll_angle_cmd)
+end
+
+-- send target angles (in degrees) to gimbal
+function send_target_angles(roll_angle_deg, pitch_angle_deg, yaw_angle_deg)
+
+  local speed = 99;
+
+  local roll_angle_hund = math.floor(roll_angle_deg*100)
+  local pitch_angle_hund = math.floor(pitch_angle_deg*100)
+  local yaw_angle_hund = math.floor(yaw_angle_deg*100)
+
+  -- send the angles for yaw and pitch.
+  set_yaw_pitch_angle(yaw_angle_hund, pitch_angle_hund, speed)
+
+  -- send the angles for yaw and pitch.
+  set_roll_angle(roll_angle_hund, speed)
+end
+
+-- send target rates (in deg/sec) to gimbal
+function send_target_rates(roll_angle_rate, pitch_angle_rate, yaw_angle_rate)
+
+  -- set the speed of gimbal yaw, pitch and roll command
+  local set_yaw_pitch_roll_rate_cmd = {35, 116, 112, 85, 71, 54, 119, 89, 80, 82}
+  -- stop control of the gimbal command
+  local gimbal_control_stop = {35, 84, 80, 85, 71, 50, 119, 80, 84, 90, 48, 48}
+
+  -- stop sending control commands if the angular velocity is too low.
+  if roll_angle_rate >= -0.0001 and roll_angle_rate <= 0.0001 and pitch_angle_rate >= -0.0001 and pitch_angle_rate <= 0.0001 and yaw_angle_rate >= -0.0001 and yaw_angle_rate <= 0.0001 then
+    -- send a stop command.
+    if gimbal_stop_order_count < 3 then
+      send_msg(gimbal_control_stop)
+      gimbal_stop_order_count = gimbal_stop_order_count + 1;
+    end
+    return
+  end
+
+  local roll_angle_rate_conv = 0;
+  local pitch_angle_rate_conv = 0;
+  local yaw_angle_rate_conv = 0;
+
+  gimbal_stop_order_count = 0
+
+  -- ensure that the speed is within a reasonable range.
+  if roll_angle_rate >= 0 then
+    roll_angle_rate_conv = math.floor(roll_angle_rate*ANGULAR_VELOCITY_CONVERSION)
+    if roll_angle_rate_conv > 99 then
+      roll_angle_rate_conv = 99
+    end
+  else
+    roll_angle_rate_conv = math.floor(roll_angle_rate*ANGULAR_VELOCITY_CONVERSION)
+    if roll_angle_rate_conv < -99 then
+      roll_angle_rate_conv = -99
+    end
+  end
+
+  if pitch_angle_rate >= 0 then
+    pitch_angle_rate_conv = math.floor(pitch_angle_rate*ANGULAR_VELOCITY_CONVERSION)
+    if pitch_angle_rate_conv > 99 then
+      pitch_angle_rate_conv = 99
+    end
+  else
+    pitch_angle_rate_conv = math.floor(pitch_angle_rate*ANGULAR_VELOCITY_CONVERSION)
+    if pitch_angle_rate_conv < -99 then
+      pitch_angle_rate_conv = -99
+    end
+  end
+
+  if yaw_angle_rate >= 0 then
+    yaw_angle_rate_conv = math.floor(yaw_angle_rate*ANGULAR_VELOCITY_CONVERSION)
+    if yaw_angle_rate_conv > 99 then
+      yaw_angle_rate_conv = 99
+    end
+  else
+    yaw_angle_rate_conv = math.floor(yaw_angle_rate*ANGULAR_VELOCITY_CONVERSION)
+    if yaw_angle_rate_conv < -99 then
+      yaw_angle_rate_conv = -99
+    end
+  end
+
+  set_yaw_pitch_roll_rate_cmd[11] = char_map[(yaw_angle_rate_conv>>4)&0x0F]
+  set_yaw_pitch_roll_rate_cmd[12] = char_map[(yaw_angle_rate_conv)&0x0F]
+
+  set_yaw_pitch_roll_rate_cmd[13] = char_map[(pitch_angle_rate_conv>>4)&0x0F]
+  set_yaw_pitch_roll_rate_cmd[14] = char_map[(pitch_angle_rate_conv)&0x0F]
+
+  set_yaw_pitch_roll_rate_cmd[15] = char_map[(roll_angle_rate_conv>>4)&0x0F]
+  set_yaw_pitch_roll_rate_cmd[16] = char_map[(roll_angle_rate_conv)&0x0F]
+
+  send_msg(set_yaw_pitch_roll_rate_cmd)
+end
+
+-- set whether the gimbal is locked or followed command
+function set_gimbal_lock(lock)
+  if gimbal_lock ~= lock then
+    gimbal_lock = lock
+    -- gimbal is followed
+    local gimbal_lock_mode = {35, 84, 80, 85, 71, 50, 119, 80, 84, 90, 48, 55}
+    if lock then
+      -- gimbal is locked
+      gimbal_lock_mode[12] = 54
+    end
+    send_msg(gimbal_lock_mode)
+  end
+end
+
+-- take picture
+function take_pic(cam_state)
+  if cam_state:take_pic_incr() and cam_state:take_pic_incr() ~= cam_pic_count then
+    cam_pic_count = cam_state:take_pic_incr()
+    if SD_status then
+      -- take a picture command.
+      local take_pic = {35, 84, 80, 85, 68, 50, 119, 67, 65, 80, 48, 49}
+      send_msg(take_pic)                          -- take a photo
+      if TOPK_DEBUG:get() > 0 then
+        gcs:send_text(MAV_SEVERITY.INFO, string.format("Topotek: took pic %u", cam_pic_count))
+      end
+    else
+      gcs:send_text(MAV_SEVERITY.WARNING, "Topotek: no sd card")
+    end
+  end
+end
+
+-- recording video
+function record_video(cam_state)
+  if cam_state:recording_video() ~= cam_rec_video then
+    cam_rec_video = cam_state:recording_video()
+
+    -- record video command.
+    local record_cmd = {35, 84, 80, 85, 68, 50, 119, 82, 69, 67, 49, 49}
+    if cam_rec_video > 0 then
+      if SD_status == false then
+        gcs:send_text(MAV_SEVERITY.WARNING, "Topotek: no sd card:")
+        do return end
+      end
+    else
+      -- stop recording
+      record_cmd[11] = 48
+      record_cmd[12] = 48
+    end
+    send_msg(record_cmd)
+    if TOPK_DEBUG:get() > 0 then
+      gcs:send_text(MAV_SEVERITY.INFO, "Topotek: rec video:" .. tostring(cam_rec_video))
+      end
+  end
+end
+
+-- set zoom specified as a rate
+function set_cam_zoom(cam_state)
+  -- zoom out = -1, hold = 0, zoom in = 1
+  local zoom_type_changed = cam_state:zoom_type() and (cam_state:zoom_type() ~= cam_zoom_type)
+  local zoom_value_changed = cam_state:zoom_value() and (cam_state:zoom_value() ~= cam_zoom_value)
+  if (zoom_type_changed or zoom_value_changed) then
+    cam_zoom_type = cam_state:zoom_type()
+    cam_zoom_value = cam_state:zoom_value()
+
+    -- zoom control command
+    local zoom_cmd = {35, 84, 80, 85, 77, 50, 119, 90, 77, 67, 48, 48}
+    if cam_zoom_type == 1 then
+      if cam_zoom_value < 0 then
+        -- zoom out
+        zoom_cmd[12] = 49
+      elseif cam_zoom_value > 0 then
+        -- zoom in
+        zoom_cmd[12] = 50
+      else
+        -- zoom stop
+        zoom_stop = true
+      end
+    end
+    send_msg(zoom_cmd)
+    if TOPK_DEBUG:get() > 0 then
+      gcs:send_text(MAV_SEVERITY.INFO, "Topotek: zoom type:" .. tostring(cam_zoom_type) .. " value:" .. tostring(cam_zoom_value))
+    end
+  end
+end
+
+-- set camera picture-in-picture mode
+function set_cam_pip()
+  if cam_pip_status ~= rc:get_aux_cached(CAM_PIP_RC_OPTION) then
+      -- switch to picture-in-picture mode command.
+      local next_pip_mode = {35, 84, 80, 85, 68, 50, 119, 80, 73, 80, 48, 65};
+      send_msg(next_pip_mode)                       -- picture-in-picture
+      cam_pip_status = rc:get_aux_cached(CAM_PIP_RC_OPTION)
+  end
+end
+
+function set_cam_focus(cam_state)
+  -- focus in = -1, focus hold = 0, focus out = 1
+  local focus_type_changed = cam_state:focus_type() and (cam_state:focus_type() ~= cam_focus_type)
+  local focus_value_changed = cam_state:focus_value() and (cam_state:focus_value() ~= cam_focus_value)
+  if (focus_type_changed or focus_value_changed) then
+    cam_focus_type = cam_state:focus_type()
+    cam_focus_value = cam_state:focus_value()
+    -- focus-related command.
+    local focus_cmd = {35, 84, 80, 85, 77, 50, 119, 70, 67, 67, 48, 48}
+    -- focus rate
+    if cam_focus_type == 1 then
+      if cam_focus_value < 0 then
+        -- focus-
+        focus_cmd[12] = 50
+      elseif cam_focus_value == 0 then
+        -- focus stop
+        focus_stop = true
+      elseif cam_focus_value > 0 then
+        -- focus+
+        focus_cmd[12] = 49
+      end
+      if TOPK_DEBUG:get() > 0 then
+        gcs:send_text(MAV_SEVERITY.INFO, "Topotek: focus")
+      end
+    end
+
+    -- check auto focus
+    if cam_focus_type == 4 then
+      -- auto focus
+      focus_cmd[11] = 49
+      if TOPK_DEBUG:get() > 0 then
+        gcs:send_text(MAV_SEVERITY.INFO, "Topotek: auto focus")
+      end
+    end
+    send_msg(focus_cmd)
+
+  end
+end
+
+-- check for changes in camera state and send messages to gimbal if required
+function check_camera_state()
+
+  -- get latest camera state from AP driver
+  local cam_state = camera:get_state(CAMERA_INSTANCE)
+  if not cam_state then
+    return
+  end
+
+  -- set camera picture-in-picture mode
+  set_cam_pip()
+
+  -- check for take picture
+  take_pic(cam_state)
+
+  -- check for start/stop recording video
+  record_video(cam_state)
+
+  -- check zoom
+  set_cam_zoom(cam_state)
+
+  -- check manual focus
+  set_cam_focus(cam_state)
+
+end
+
+-- tracking point
+function track_point(tracking_p1x, tracking_p1y)
+  -- turn tracking point on
+  local track_point_x = math.floor((tracking_p1x*TRACK_TOTAL_WIDTH - 960) / 0.96)
+  local track_point_y = math.floor((tracking_p1y*TRACK_TOTAL_HEIGHT - 540) / 0.54)
+
+  -- tracking range after conversion
+  local track_width = math.floor(TRACK_RANGE/0.96)
+  local track_height = math.floor(TRACK_RANGE/0.54)
+  -- begin track command
+  local begin_track_cmd = {35, 116, 112, 85, 68, 65, 119, 76, 79, 67}
+
+  begin_track_cmd[11] = (track_point_x >> 8) & 0xFF
+  begin_track_cmd[12] = (track_point_x) & 0xFF
+
+  begin_track_cmd[13] = (track_point_y >> 8) & 0xFF
+  begin_track_cmd[14] = (track_point_y) & 0xFF
+
+  begin_track_cmd[15] = (track_width >> 8) & 0xFF
+  begin_track_cmd[16] = (track_width) & 0xFF
+
+  begin_track_cmd[17] = (track_height >> 8) & 0xFF
+  begin_track_cmd[18] = (track_height) & 0xFF
+
+  begin_track_cmd[19] = 0
+  begin_track_cmd[20] = 1
+
+  send_msg(begin_track_cmd)
+  gcs:send_text(MAV_SEVERITY.INFO, "Topotek: tracking point ON")
+end
+
+-- tracking rectangle
+function tracking_rect(tracking_p1x, tracking_p1y, tracking_p2x, tracking_p2y)
+  -- upper left point
+  local upper_leftx;
+  local upper_lefty;
+
+  -- bottom right point
+  local down_rightx;
+  local down_righty;
+
+  -- frame selection range
+  local frame_selection_width;
+  local frame_selection_height;
+
+  if tracking_p1x < tracking_p2x then
+    upper_leftx = tracking_p1x*TRACK_TOTAL_WIDTH
+    down_rightx = tracking_p2x*TRACK_TOTAL_WIDTH
+  else
+    down_rightx = tracking_p1x*TRACK_TOTAL_WIDTH
+    upper_leftx = tracking_p2x*TRACK_TOTAL_WIDTH
+  end
+
+  if tracking_p1y < tracking_p2y then
+    upper_lefty = tracking_p1y*TRACK_TOTAL_HEIGHT
+    down_righty = tracking_p2y*TRACK_TOTAL_HEIGHT
+  else
+    down_righty = tracking_p1y*TRACK_TOTAL_HEIGHT
+    upper_lefty = tracking_p2y*TRACK_TOTAL_HEIGHT
+  end
+
+  -- calculated tracking range
+  frame_selection_width = down_rightx - upper_leftx;
+  frame_selection_height = down_righty - upper_lefty;
+
+  if frame_selection_width <= 0 or frame_selection_height <= 0 then
+    return
+  end
+
+  -- the converted tracking center
+  local track_center_x = math.floor((upper_leftx + frame_selection_width/2 - 960) /  0.96)
+  local track_center_y = math.floor((upper_lefty + frame_selection_height/2 - 540) /  0.54)
+
+  -- tracking range after conversion
+  local track_width = math.floor(frame_selection_width / 0.96)
+  local track_height = math.floor(frame_selection_height / 0.54)
+
+
+  -- begin track command
+  local begin_track_cmd = {35, 116, 112, 85, 68, 65, 119, 76, 79, 67}
+
+  begin_track_cmd[11] = (track_center_x >> 8) & 0xFF
+  begin_track_cmd[12] = (track_center_x) & 0xFF
+
+  begin_track_cmd[13] = (track_center_y >> 8) & 0xFF
+  begin_track_cmd[14] = (track_center_y) & 0xFF
+
+  begin_track_cmd[15] = (track_width >> 8) & 0xFF
+  begin_track_cmd[16] = (track_width) & 0xFF
+
+  begin_track_cmd[17] = (track_height >> 8) & 0xFF
+  begin_track_cmd[18] = (track_height) & 0xFF
+
+  begin_track_cmd[19] = 0
+  begin_track_cmd[20] = 1
+
+  send_msg(begin_track_cmd)
+  gcs:send_text(MAV_SEVERITY.INFO, "Topotek: tracking rectangle ON")
+end
+
+-- check for changes in tracking state and send messages to gimbal if required
+function check_tracking_state()
+
+  -- get latest camera state from AP driver
+  local cam_state = camera:get_state(CAMERA_INSTANCE)
+  if not cam_state then
+    return
+  end
+
+  -- check for change in tracking state
+  local tracking_type_changed = cam_state:tracking_type() ~= last_tracking_type
+  local tracking_type_p1_changed = (cam_state:tracking_p1():x() ~= last_tracking_p1x) or (cam_state:tracking_p1():y() ~= last_tracking_p1y)
+  local tracking_type_p2_changed = (cam_state:tracking_p2():x() ~= last_tracking_p2x) or (cam_state:tracking_p2():y() ~= last_tracking_p2y)
+
+
+  last_tracking_type = cam_state:tracking_type()
+  last_tracking_p1x = cam_state:tracking_p1():x()
+  last_tracking_p1y = cam_state:tracking_p1():y()
+  last_tracking_p2x = cam_state:tracking_p2():x()
+  last_tracking_p2y = cam_state:tracking_p2():y()
+
+  if (last_tracking_type == 0) and tracking_type_changed then
+    -- turn off tracking
+    local stop_track_cmd = {35, 84, 80, 85, 68, 50, 119, 84, 82, 67, 48, 49}
+    send_msg(stop_track_cmd)                      -- stop track
+    is_tracking = false
+    gcs:send_text(MAV_SEVERITY.INFO, "Topotek: tracking OFF")
+  end
+
+  if (last_tracking_type == 1) and (tracking_type_changed or tracking_type_p1_changed) then
+    -- turn tracking point on
+    track_point(last_tracking_p1x, last_tracking_p1y)
+    is_tracking = true
+  end
+
+  if (last_tracking_type == 2) and (tracking_type_changed or tracking_type_p1_changed or tracking_type_p2_changed) then
+    -- turn tracking rectangle on
+    tracking_rect(last_tracking_p1x, last_tracking_p1y, last_tracking_p2x, last_tracking_p2y)
+    is_tracking = true
+  end
+end
+
+-- get information form gimbal
+function get_gimbal_info()
+  if send_count%5 == 0 then
+    -- request memory card information within the specified time
+    local get_gimbal_sdcard_info = {35, 84, 80, 85, 68, 50, 114, 83, 68, 67, 48, 48}
+    send_msg(get_gimbal_sdcard_info)              -- get gimbal memory card information
+
+    -- if trace mode is enabled, trace status information is requested within a specified period of time
+    if is_tracking then
+      local get_gimbal_track_status = {35, 84, 80, 85, 68, 50, 114, 84, 82, 67, 48, 48}
+      send_msg(get_gimbal_track_status)           -- get gimbal tracking status
+    end
+  end
+
+  -- the gimbal attitude is obtained every second, and the gimbal will continue to send attitude information during the next period
+  if send_count%100 == 0 then
+    local get_gimbal_attitude = {35, 84, 80, 85, 71, 50, 119, 71, 65, 65, 48, 49}
+    send_msg(get_gimbal_attitude)                 -- get gimbal attitude
+    send_count = 0;
+  end
+  send_count = send_count + 1
+end
+
+-- initialize internal parameters.
+function init_value()
+  -- get picture-in-picture mode
+  cam_pip_status = rc:get_aux_cached(CAM_PIP_RC_OPTION)
+
+  -- set char_map
+  for i = 0, 9 do
+    char_map[i] = i + 48
+  end
+
+  for i = 10, 15 do
+    char_map[i] = i + 55
+  end
+
+  -- set number_map
+  for i = 0, 9 do
+    number_map[i + 48] = i
+  end
+
+  for i = 97, 102 do
+    number_map[i] = (i - 87)
+  end
+
+  for i = 65, 70 do
+    number_map[i] = (i - 55)
+  end
+end
+
+-- find and initialise serial port connected to gimbal
+function init()
+  -- check mount parameter
+  if MNT1_TYPE:get() ~= 9 then
+    gcs:send_text(MAV_SEVERITY.CRITICAL, "Topotek: set MNT1_TYPE=9")
+    do return end
+  end
+
+  -- check cam type parametr
+  if CAM1_TYPE:get() ~= 7 then
+    gcs:send_text(MAV_SEVERITY.CRITICAL, "Topotek: set CAM1_TYPE=7")
+    do return end
+  end
+
+  -- find and init first instance of SERIALx_PROTOCOL = 28 (Scripting)
+  uart = serial:find_serial(0)
+  if uart == nil then
+    gcs:send_text(3, "Topotek: no SERIALx_PROTOCOL = 28") -- MAV_SEVERITY_ERR
+  else
+    uart:begin(115200)
+    uart:set_flow_control(0)
+    initialised = true
+    gcs:send_text(MAV_SEVERITY.INFO, "Topotek: started")
+  end
+
+  -- initialize internal parameters.
+  init_value()
+end
+
+function update()
+
+  -- initialise connection to gimbal
+  if not initialised then
+    init()
+    return update, INIT_INTERVAL_MS
+  end
+  -- consume incoming bytes
+  read_incoming_packets()
+
+  -- send stop commands twice to prevent the gimbal from not receiving the command
+  repeat_stop_cmd()
+
+  -- check camera state and send control messages
+  check_camera_state()
+
+  -- check tracking state and send tracking control messages
+  check_tracking_state()
+
+  -- get information form gimbal
+  get_gimbal_info()
+
+  -- send target angle to gimbal
+  local roll_deg, pitch_deg, yaw_deg, deg_yaw_is_ef = mount:get_angle_target(MOUNT_INSTANCE)
+
+  if roll_deg and pitch_deg and yaw_deg then
+
+    -- set whether the gimbal is locked or followed command
+    set_gimbal_lock(deg_yaw_is_ef)
+    send_target_angles(roll_deg, pitch_deg, yaw_deg)
+    return update, UPDATE_INTERVAL_MS
+  end
+
+  -- send target rate to gimbal
+  local roll_degs, pitch_degs, yaw_degs, degs_yaw_is_ef = mount:get_rate_target(MOUNT_INSTANCE)
+
+  if roll_degs and pitch_degs and yaw_degs then
+    -- set whether the gimbal is locked or followed command
+    set_gimbal_lock(degs_yaw_is_ef)
+    send_target_rates(roll_degs, pitch_degs, yaw_degs)
+    return update, UPDATE_INTERVAL_MS
+  end
+
+  return update, UPDATE_INTERVAL_MS
+end
+
+return update()
diff --git a/libraries/AP_Scripting/drivers/mount-topotek-driver.md b/libraries/AP_Scripting/drivers/mount-topotek-driver.md
new file mode 100755
index 00000000000000..d6608ac005516b
--- /dev/null
+++ b/libraries/AP_Scripting/drivers/mount-topotek-driver.md
@@ -0,0 +1,19 @@
+# Mount Topotek Driver
+
+Topotek gimbal driver lua script
+
+# How to use
+
+    Connect gimbal UART to one of the autopilot's serial ports
+    Set SERIALx_PROTOCOL = 28 (Scripting) where "x" corresponds to the serial port connected to the gimbal
+    Set SERIALx_BAUD = 115 (115200)
+    Set SCR_ENABLE = 1 to enable scripting and reboot the autopilot
+    Set MNT1_TYPE = 9 (Scripting) to enable the mount/gimbal scripting driver
+    Set CAM1_TYPE = 7 (Scripting) to enable the camera scripting driver
+    Set RCx_OPTION = 300 (Scripting1) to control which camera's picture-in-picture mode.
+    Set SCR_HEAP_SIZE = 120000
+    Copy this script to the autopilot's SD card in the APM/scripts directory and reboot the autopilot
+    Set MNT1_RC_RATE to 90 (deg/s) to control gimbal movement.
+    Optionally set TOPK_DEBUG = 1 or 2 to increase level of debug output to the GCS
+    Reboot the autopilot
+