a serial to websocket wifi bridge for an easy wireless connection to a non-"Connected" botvac model
This project was tested with a Neato Botvac 85 and an ESP8266 ESP-12F (Witty Cloud Module).
I'm using a Witty Cloud Module (for example this one). This is an ESP-12F module with a breakout board for easier development and it can be USB powered with power regulation. It also includes a daughter board with a serial bridge and all resistors etc. for easier flashing.
There is a connector on each side of the main board (labled P7 on top side and P25 on the bottom side) at the front right corner of the bot. The pins are as follows:
Top:
- Serial Transmit
- Ground
- Serial Receive
Bottom:
- +3.3 volt
- not connected
- Ground
The following connections need to be made between the bot and the ESP module:
- TX bot to RX ESP
- RX bot to TX ESP
- GND bot to GND ESP
- 3.3V bot to VCC ESP (Note: If you are using an ESP module that has a built-in 5V -> 3.3V power regulator (like the Witty Cloud Module), you need to solder the 3.3V connection directly to the ESP module as the VCC pin of the Witty Cloud Module is connected to the 5V of the power regulator and not directly to the 3.3V VCC of the ESP module itself)
The 3.3V connection on the bot is handled by the power regulation circuitry, so there should be no risk of the module completly draining the battery. The module power draw is also included in the GetCharger Discharge_mAH total. When powered by a bench power supply, the module I'm using had a maximum power draw of 80mA to 100mA.
The wires should be long enough so they don't interfere with the opening and closing of the top case. I would also add some connectors to the wires so the ESP module can be disconnected from the bot for easier firmware updates. I used Dupont connectors.
The module is glued with strong double sided to the top case on the opposite side of the display:
Required:
- Arduino IDE: https://www.arduino.cc/en/Main/Software
- ESP8266 core for Arduino: https://github.com/esp8266/Arduino
- arduinoWebSockets: https://github.com/Links2004/arduinoWebSockets
Install all software according to the documentation. Depending on what module/programming adaptor you are using you might also need to install the apropriate drives.
If you haven't already, check out this repository and open the botvac-wifi.ino file in the Arduino IDE. Replace the XXX with your WiFi SSID and password. Connect the ESP module to the computer and click the right-facing arrow to compile and upload the software to the ESP module.
The software includes multicast DNS (mDNS), so you should be able to connect to the bot with http://neato.local for a simple websocket interface or use ws://neato.local:81 for a direct websocket connection. Alternatively you can check your DHCP to find out the IP adress of the bot.
For convenience and safety purposes, "TestMode off" is always send to the bot if a user disconnects.
The websocket server is listening on port 81. Everything that you send via the websocket connection is directly sent to the serial interface and the results from the serial interface are returned via the websocket connection (see also limitations).
The software also includes a simple HTML interface for the websocket connection. Connect with a browser to the bot to see it. The websocket connection is automatically established in the background. Type a command and press enter to send the command. The results are automatically displayed. You can disconnect by typing /disconnect or clear the screen by typing /clear.
Send help to the bot to see an overview of all commands or send help commandname to get help for a specific command. Neato also offers a programmers manual
- Only one user can be connected at the same time. If a new user connects, the old user is disconnected. This is intentional and by design to prevent issues with the bot and data corruption with multiple users.
- The websocket responses contain only ASCII characters. All special characters get replaced by a underscore. This is only relevant for the text of non-english error messages. The error code is transmitted unchanged. This a limitation of the microcontroller/IDE.
- Responses that are to big to fit into a single TCP packet are split up into multiple websocket messages. Always check for the response for the end of file marker (ctrl-z; \x1A). This a workaround for a possible bug in the network APIs (see also Links2004/arduinoWebSockets#85).
The (sadly) necessary disclaimer:
THE SOFTWARE AND INFORMATION IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE, INFORMATION OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.