update

docs/pico_hid.md

@@ -135,10 +135,16 @@ getting rid of the transistor for the Reset line and level shifter for RX/TX (MO
 
     * The `GP22` on the Pico is connected directly to the `GND`. This enables UART mode instead of default SPI.
 
-    * In the original V0, `GPIO4` on the Raspberry Pi was used for the Reset line. Now we recommend using `GPIO25`
+    * In the original V0, `GPIO4` [on the Raspberry Pi](https://pinout.xyz) was used for the Reset line. Now we recommend using `GPIO25`
       for consistency reasons. However, you can use `GPIO4` by changing the `reset_pin` value in the config example below.
       On the scheme, this is a yellow wire, the `RUN (Pico) -> GPIO25 (Pi)` line.
 
+    ??? example "Simple wiring diagram"
+        <img src="serial_breadboard.png" />
+
+    ??? example "Electrical schematic diagram"
+        <img src="serial_scheme.png" />
+
     ??? example "Configs"
         * Don't add line `dtoverlay=spi0-1cs` to the `/boot/config.txt` file. It's only needed for SPI.