# Connections & Ports

{% hint style="info" %}
This baseboard is compatible with both Pixhawk 5X & 6X, and any flight controller that follow the Pixhawk Bus Standard.
{% endhint %}

<figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2FHdcpbFPIbRT0ouM6KUyV%2FCM4_Baseboard_Ports.jpg?alt=media&#x26;token=bca3ecc1-7189-4821-9236-0a08a31b0709" alt=""><figcaption></figcaption></figure>

{% hint style="info" %}
This baseboard is compatible with both Pixhawk 5X & 6X, and any flight controller that follow the Pixhawk Bus Standard.
{% endhint %}

### **Connection Between RPi CM4 & Flight Controller:**

FC Module is internally connected to RPi CM4 through TELEM2

* CM4 GPIO14 <-> FMU TXD TELEM2
* CM4 GPIO15 <-> FMU RXD TELEM2
* CM4 GPIO16 <-> FMU CTS TELEM2
* CM4 GPIO17 <-> FMU RTS TELEM2

### **CM4 Slave USB-C port:**

CM4 USB Device Port. Use for CM4 Power and image flash. Max input voltage: 5V

### **CM4 Host1 & Host2  USB-C Port:**&#x20;

CM4 USB Host port. 1A Current output limit for each port.

### **Micro HDMI:**&#x20;

CM4 Video Output

### **Dip Switch**

![](https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2Fvthc40V3NUXIluDBXlLn%2FCM4_DipSwitch.jpg?alt=media\&token=30486de3-c56b-4290-bc82-6608db36dc78)

|      | CM4 Slave                                     | CM4 Host1&2                                    |
| ---- | --------------------------------------------- | ---------------------------------------------- |
| RPI  | <p>Data Connected</p><p>Power IN and Data</p> | <p>Data Not Connected</p><p>Power out only</p> |
| EMMC | <p>Data Not Connected</p><p>Power IN only</p> | <p>Data Connected</p><p>Power out and Data</p> |

<figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2FXilDQZLsYfrk92ic1T6v%2FCM4_USB_Switch.png?alt=media&#x26;token=b1aee0e9-c510-44d2-bb46-490058656c70" alt=""><figcaption></figcaption></figure>

{% hint style="info" %}
Refer to this diagram for location of pin1. All connectors are JST GH 1.25 mm Pitch unless noted otherwise.&#x20;

![](https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2F5ztMPc8sZRkgBLuofQ25%2FPin%20Number.png?alt=media\&token=33990df2-0d2d-4b45-9a4f-ead799af93fe)
{% endhint %}

### **CM4 ETH  port**

| Pin       | Signal       | Volt  |
| --------- | ------------ | ----- |
| 1(red)    | CM4\_TRD0\_P | +3.3V |
| 2(pink)   | CM4\_TRD0\_N | +3.3V |
| 3(yellow) | CM4\_TRD1\_P | +3.3V |
| 4(green)  | CM4\_TRD1\_N | +3.3V |
| 5(brown)  | CM4\_TRD2\_P | +3.3V |
| 6(blue)   | CM4\_TRD2\_N | +3.3V |
| 7(purple) | CM4\_TRD3\_P | +3.3V |
| 8(black)  | CM4\_TRD3\_N | +3.3V |

### **FC ETH Port**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | RXN        | +3.3V    |
| 2(black) | RXP        | +3.3V    |
| 3(black) | TXN        | +3.3V    |
| 4(black) | TXP        | +3.3V    |

<figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2FafeCsTbUXasWlZcCQT0m%2FCM4%20Ethernet.png?alt=media&#x26;token=f71ad010-d530-443c-90a4-46e291c3d14f" alt=""><figcaption><p>FC &#x26; CM4 connected via ethernet using cabled provided.</p></figcaption></figure>

### **FAN port**

{% hint style="info" %}
The 5V source for the fan is not shared with the USB 5V that powers the RPi compute module.
{% endhint %}

| Pin      | Signal | Volt |
| -------- | ------ | ---- |
| 1(red)   | VCC    | +5V  |
| 2(black) | GND    | GND  |

### **CAMERA  Port** (Use for CSI Camera IN)

| Pin | Signal            | Volt  |
| --- | ----------------- | ----- |
| 1   | GND               | GND   |
| 2   | CM4\_CAM1\_D0\_N  | +3.3V |
| 3   | CM4\_CAM1\_D0\_P  | +3.3V |
| 4   | GND               | GND   |
| 5   | CM4\_CAM1\_D1\_N  | +3.3V |
| 6   | CM4\_CAM1\_D1\_P  | +3.3V |
| 7   | GND               | GND   |
| 8   | CM4\_CAM1\_CLK\_N | +3.3V |
| 9   | CM4\_CAM1\_CLK\_P | +3.3V |
| 10  | GND               | GND   |
| 11  | CM4\_CAM1\_D2\_N  | +3.3V |
| 12  | CM4\_CAM1\_D2\_P  | +3.3V |
| 13  | GND               | GND   |
| 14  | CM4\_CAM1\_D3\_N  | +3.3V |
| 15  | CM4\_CAM1\_D3\_P  | +3.3V |
| 16  | GND               | GND   |
| 17  | CM4\_CAM1\_GPIO   | +3.3V |
| 18  | No Connected      | --    |
| 19  | GND               | GND   |
| 20  | CM4\_I2C0\_SCL    | +3.3V |
| 21  | CM4\_I2C0\_SDA    | +3.3V |
| 22  | CM4\_VDD\_3V3     | +3.3V |

### **Power1 (Main) & Power2 Port (Backup)** (2.00mm Pitch CLIK-Mate)

| **Pin**  | **Signal**      | **Volt** |
| -------- | --------------- | -------- |
| 1(red)   | VDD5V\_BRICK1/2 | +5V      |
| 2(black) | VDD5V\_BRICK1/2 | +5V      |
| 3(black) | SCL1/2          | +3.3V    |
| 4(black) | SDA1/2          | +3.3V    |
| 5(black) | GND             | GND      |
| 6(black) | GND             | GND      |

### **Telem1, Telem2, Telem3 ports**

| **Pin**  | **Signal**     | **Volt** |
| -------- | -------------- | -------- |
| 1(red)   | VCC            | +5V      |
| 2(black) | TX7/5/2 (out)  | +3.3V    |
| 3(black) | RX7/5/2 (in)   | +3.3V    |
| 4(black) | CTS7/5/2 (in)  | +3.3V    |
| 5(black) | RTS7/5/2 (out) | +3.3V    |
| 6(black) | GND            | GND      |

### **GPS 1 Port**

| **Pin**   | **Signal**          | **Volt** |
| --------- | ------------------- | -------- |
| 1(red)    | VCC                 | +5V      |
| 2 black)  | TX1(out)            | +3.3V    |
| 3(black)  | RX1(in)             | +3.3V    |
| 4(black)  | SCL1                | +3.3V    |
| 5(black)  | SDA1                | +3.3V    |
| 6(black)  | SAFETY\_SWITCH      | +3.3V    |
| 7(black)  | SAFETY\_SWITCH\_LED | +3.3V    |
| 8(black)  | VDD\_3V3            | +3.3V    |
| 9(black)  | BUZZER-             | 0\~5V    |
| 10(black) | GND                 | GND      |

### **GPS 2 Port**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | VCC        | +5V      |
| 2 black) | TX8(out)   | +3.3V    |
| 3(black) | RX8(in)    | +3.3V    |
| 4(black) | SCL2       | +3.3V    |
| 5(black) | SDA2       | +3.3V    |
| 6(black) | GND        | GND      |

### **CAN1, CAN2 ports**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | VCC        | +5V      |
| 2(black) | CANH1/2    | +3.3V    |
| 3(black) | CANL1/2    | +3.3V    |
| 4(black) | GND        | GND      |

### **Uart4 & I2C port**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | VCC        | +5V      |
| 2(black) | TX4(out)   | +3.3V    |
| 3(black) | RX4(in)    | +3.3V    |
| 4(black) | SCL3       | +3.3V    |
| 5(black) | SDA3       | +3.3V    |
| 6(black) | NFC\_GPIO  | +3.3V    |
| 7(black) | GND        | GND      |

### **SPI Port**

| **Pin**   | **Signal**   | **Volt** |
| --------- | ------------ | -------- |
| 1(red)    | VCC          | +5V      |
| 2 (black) | SPI6\_SCK    | +3.3V    |
| 3(black)  | SPI6\_MISO   | +3.3V    |
| 4(black)  | SPI6\_MOSI   | +3.3V    |
| 5(black)  | SPI6\_CS1    | +3.3V    |
| 6(black)  | SPI6\_CS2    | +3.3V    |
| 7(black)  | SPIX\_SYNC   | +3.3V    |
| 8(black)  | SPI6\_DRDY1  | +3.3V    |
| 9(black)  | SPI6\_DRDY2  | +3.3V    |
| 10(black) | SPI6\_nRESET | +3.3V    |
| 11(black) | GND          | GND      |

### **USB Port**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | VBUS       | +5V      |
| 2(black) | DM         | +3.3V    |
| 3(black) | DP         | +3.3V    |
| 4(black) | GND        | GND      |

### **I2C Port**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | VCC        | +5V      |
| 2(black) | SCL3       | +3.3V    |
| 3(black) | SDA3       | +3.3V    |
| 4(black) | GND        | GND      |

### **ETH Port**

| **Pin**  | **Signal** | **Volt** |
| -------- | ---------- | -------- |
| 1(red)   | RXN        | +3.3V    |
| 2(black) | RXP        | +3.3V    |
| 3(black) | TXN        | +3.3V    |
| 4(black) | TXP        | +3.3V    |

### **AD\&IO Port**

| **Pin**  | **Signal**      | **Volt** |
| -------- | --------------- | -------- |
| 1(red)   | VCC             | +5V      |
| 2(black) | FMU\_CAP1       | +3.3V    |
| 3(black) | FMU\_BOOTLOADER | +3.3V    |
| 4(black) | FMU\_RST\_REQ   | +3.3V    |
| 5(black) | NARMED          | +3.3V    |
| 6(black) | ADC1\_3V3       | +3.3V    |
| 7(black) | ADC1\_6V6       | +6.6V    |
| 8(black) | GND             | GND      |

### **DSM RC Port** (JST-ZH 1.5mm Pitch)

| **Pin**   | **Signal**         | **Volt** |
| --------- | ------------------ | -------- |
| 1(yellow) | VDD\_3V3\_SPEKTRUM | +3.3V    |
| 2(black)  | GND                | GND      |
| 3(gray)   | DSM/SPEKTRUM IN    | +3.3V    |

### **RC IN Port**

| **Pin** | **Signal**   | **Volt** |
| ------- | ------------ | -------- |
| S       | SBUS/PPM in  | +3.3V    |
| +       | VDD\_5V \_RC | +5V      |
| -       | GND          | GND      |

### **IO Debug Port** (JST-SH 1mm Pitch)

| **Pin**   | **Signal**       | **Volt** |
| --------- | ---------------- | -------- |
| 1(red)    | IO\_VDD\_3V3     | +3.3V    |
| 2 black)  | IO\_USART1\_TX   | +3.3V    |
| 3(black)  | NC               | --       |
| 4(black)  | IO\_SWD\_IO      | +3.3V    |
| 5(black)  | IO\_SWD\_CK      | +3.3V    |
| 6(black)  | IO\_SWO          | +3.3V    |
| 7(black)  | IO\_SPARE\_GPIO1 | +3.3V    |
| 8(black)  | IO\_SPARE\_GPIO2 | +3.3V    |
| 9(black)  | IO\_nRST         | +3.3V    |
| 10(black) | GND              | GND      |

### **FMU Debug Port** (JST-SH 1mm Pitch)

| **Pin**   | **Signal**           | **Volt** |
| --------- | -------------------- | -------- |
| 1(red)    | FMU\_VDD\_3V3        | +3.3V    |
| 2 black)  | FMU\_USART3\_TX      | +3.3V    |
| 3(black)  | FMU\_USART3\_RX      | +3.3V    |
| 4(black)  | FMU\_SWD\_IO         | +3.3V    |
| 5(black)  | FMU\_SWD\_CK         | +3.3V    |
| 6(black)  | SPI6\_SCK\_EXTERNAL1 | +3.3V    |
| 7(black)  | NFC\_GPIO            | +3.3V    |
| 8(black)  | PH11                 | +3.3V    |
| 9(black)  | FMU\_nRST            | +3.3V    |
| 10(black) | GND                  | GND      |

### **RSSI Port**

| **Pin** | **Signal**         | **Volt** |
| ------- | ------------------ | -------- |
| S       | SBUS\_OUT/RSSI\_IN | +3.3V    |
| +       | VDD\_SERVO         | 0\~36V   |
| -       | GND                | GND      |

### **FMU PWM OUT (AUX)**

| **Pin** | **Signal**  | **Volt** |
| ------- | ----------- | -------- |
| S       | FMU\_CH1\~8 | +3.3V    |
| +       | VDD\_SERVO  | 0\~36V   |
| -       | GND         | GND      |

### **I/O PWM OUT (MAIN)**

| **Pin** | **Signal** | **Volt** |
| ------- | ---------- | -------- |
| S       | IO\_CH1\~8 | +3.3V    |
| +       | VDD\_SERVO | 0\~36V   |
| -       | GND        | GND      |