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+# Poky Pow Design Document
+
+Working document for the Poky Pow project.
+
+## Use case:
+
+PC or server owners plug that pcb in their USB2.0 header, connect power, resest and power led.
+With that, they can control their PC with Home Assistant.
+
+# Software
+
+Everything is done via ESPHome.
+
+
+# Requirements:
+
+Brain is the ESP32-C3-MINI-1U.
+- for its external antenna
+- Has Bluetooth and WiFi (both needed for [Made for ESPHome](https://esphome.io/guides/made_for_esphome.html) approval)
+- Supported by ESPHome
+  - esp32, esp32s2, esp32s3, esp32c3 and esp32h2
+  - Source: https://esphome.io/components/esp32.html#configuration-variables
+- Docs here: https://www.espressif.com/sites/default/files/documentation/esp32-c3-mini-1_datasheet_en.pdf
+
+
+- ESP32 (No bluetooth)
+- ESP32-S2 not possible (No bluetooth), no serial usb
+- ESP32-S3 (bluetooth, usb, but more expensice?)
+- ESP32-C2 (No ESPHome Support? riscV,
+- Esp32c3 (more memory, same as c2 with risc V), usb serial
+- Esp32h2 (thread, zigbee, riscV, no wifi)
+
+
+## USB-C Connector
+
+- for flashing and debugging
+- for power
+- Connected via the CH340C
+
+## USB2.0 9 Pin Plug
+
+- for plugging into the motherboard
+- for power
+- will be wired with data from USB, but not used in ESPHome from the start
+- connected via the internal serial of the ESP32-C3-MINI-1U
+
+## Motherboard And PC Case Pins
+
+Motherboard and PC Case pins must be seperated.
+That way we use the PC Case pins as an input and can do any action with them in the software.
+
+
+- Power LED (Needs to be able to detect if the LED is on/off)
+- Reset Button (Needs to short the connection for a certain amount of time in order to reset the PC)
+- Power Button (Needs to short the connection for a certain amount of time in order to power on, power off or hard reset the PC)
+
+- PC case pins:
+  - power: GPIO21
+  - reset: GPIO20
+  - power LED: GPIO18
+- Motherboard pins:
+  - power: ?
+  - reset: ?
+  - power LED: ?
+
+Other pins:
+
+- RGB LED: GPIO19
+
+
+## Testpoints
+
+- As many as needed
+
+## Extra GPIO
+
+- when space is not issue lets expose as many as possible
+
+
+## Antenna
+
+The ESP32-C3-MINI-1U has an external antenna connector and NO onboard antenna.
+Hence we need to use an external antenna.
+
+I found this one:
+
+[Adafruit Accessories WiFi Antenna with w.FL / MHF3 / IPEX3 Connector](https://eu.mouser.com/ProductDetail/Adafruit/5445?qs=vvQtp7zwQdMvbE1TBlHDrA%3D%3D)
+
+
+## Power
+
+There are 2 potential power sources:
+- USB-C connector
+- 9 Pin Plug
+
+Both could be connected and we need to make sure to damage the PCB or the mainboard.
+
+## PCB size and form
+
+- 3 holes for 3D printed base/case
+- measurements (roughly, taken form the Silverstone ES03-WIFI):
+   - width: 25.2mm (most critical, since there might be other header, etc on the mainboard)
+   - height: 8mm 
+   - depth: 45.6mm
+
+## Buttons
+
+- power and reset button if needed
+
+## LED
+
+We need a LED compatible with ESPHome:
+https://esphome.io/components/light/