document hardware connection

Author: dan-s-github

README.md

@@ -23,9 +23,12 @@ You can find the sample configuration YAML and image in the [`docs/home-assistan
 ## Components
 
 - m5stack Canbus Kit
-- 5V power supply adapter
+- 5V power supply 
+  - standdard usb power adapter
+  - [step-down converter](https://www.aliexpress.com/item/1005002797242220.html) \
+    [usb-c connector](https://www.aliexpress.com/item/1005005068786615.html) (2pin type-c male)
 - Any ethernet cable (RJ45 connector)
-- A micro USB cable to connect the m5stack Atom Lite to your computer
+- A USB-C cable to connect the m5stack Atom Lite to your computer
 
 ### Prepare Atom Lite
 
@@ -61,11 +64,66 @@ This uses esphome to prepare the atom lite for home assistant
 
 6. Use the [zehnder-comfoair-can.yaml](zehnder-comfoair-can.yaml) as template to edit your newly created yaml file
 
-To be continued...    
+### Hardware
+
+1. Strip one side of the ethernet cable
+2. Connect the orange, white-orange, white-green wires to the `m5stack can` connector (see diagram + pictures below).
+3. Connect the blue and white-green to the step-down converter
+4. Connect the usb-c connector to the m5stack atom controller
+5. Connect the other side of the cable to the RJ45 port of the ventilation unit (located at the top, behind the sliding cover).
+
+
+### Connection diagram
+
+```
+
+|----------------+ 
+|                | 
+|   [ComfoAir]   | 
+|                |                                           m5stack can
+|                |      +++++++++++++++++++++            +-----------------+
+|           RJ45 o------|   (orange)  CAN-H o------------o CAN-H           |
+|----------------+      | (w/orange)  CAN-L o------------o CAN-L   usb-c   O-----+
+                        |  (w/green)    GND o-------+----o GND             |     |
+                        |     (blue)   +12V o---+   |    +-----------------+     |
+                        +++++++++++++++++++++   |   |                            |
+                                                |   |    +-----------+           |
+                                                |   +----o           o----+      |
+                                                |        |  Mini560  |    +------+
+                                                +--------o           o----+ 
+                                                         +-----------+
+```
+
+Here some pictures of the current setup connected to the Zehnder ComfoAir Q
+
+![m5stack with step-down converter][m5stack_mini560]
+![m5stack test installation][m5stack_installed]
+
+
+## Credits
+
+Based on https://github.com/yoziru/esphome-zehnder-comfoair which uses an [Olimex ESP32-EVB](https://github.com/OLIMEX/ESP32-EVB) with CAN interface.
+
+Inspired by
+
+- https://github.com/vekexasia/comfoair-esp32
+- https://github.com/michaelarnauts/aiocomfoconnect
+- https://github.com/felixstorm/esphome-custom-components
+- [https://github.com/mat3u/comfoair-esp32](https://github.com/mat3u/comfoair-esp32/tree/hacomfoairmqtt-compatibility)
+- [https://github.com/hcouplet/comfoair-esp32](https://github.com/hcouplet/comfoair-esp32/tree/hacomfoairmqtt-compatibility)
+
+A lot of this repo was inspired by the reverse engineering [here](https://github.com/marco-hoyer/zcan/issues/1).
+
+- [ComfoControl Protocol](https://github.com/michaelarnauts/aiocomfoconnect/blob/master/docs/PROTOCOL.md)
+- [RMI PROTOCOL](https://github.com/michaelarnauts/aiocomfoconnect/blob/master/docs/PROTOCOL-RMI.md)
+- [PDO PROTOCOL](https://github.com/michaelarnauts/aiocomfoconnect/blob/master/docs/PROTOCOL-PDO.md)
+
 
 [ha_dashboard_top]: ./docs/ha_dashboard_top.png
 [ha_dashboard_bottom]: ./docs/ha_dashboard_bottom.png
 [m5stack_can]: ./docs/m5stack.png
+[m5stack_mini560]: ./docs/m5stack_mini560.png
+[m5stack_installed]: ./docs/m5stack_installed.png
 [esphome_adopt]: ./docs/esphome_adopt.png
 [esphome_rename]: ./docs/esphome_rename.png
 [esphome_ready]: ./docs/esphome_ready.png