# Electrical Interfaces
## **I/O and Electrical Panel**
### **USB-C**
Configured as ethernet adapter.
Functionality:
* connection to payload
* mass storage (e.g. flash drive)
* firmware updates
{% hint style="info" %}
It is not possible to power Astro via this port. For example, to update firmware or download logs, power Astro with a battery.
{% endhint %}
### Payload
Connector type: JST-ZPD 26-pin
This connector can be accessed directly or to pass connections to the [Smart Dovetail](/astro/other-user-manuals/ecosystem/development-tools/payload-mounting-interfaces.md#smart-dovetail) connector.
The mating connector to build a payload cable is [ZPDR-26V-S](https://www.digikey.com/en/products/detail/jst-sales-america-inc/ZPDR-26V-S/2472569).
### TELEM3
Connector: JST GH 6-pin
### **AUX UART**
Connector: JST GH 6-pin
### **PWM**
Connector: headers, 0.1 inch spacing
PWM outputs are active when the aircraft is powered on.
#### **Setup**
{% tabs %}
{% tab title="2.0.19 and up" %}
The PWM outputs on the Astro are controlled with the PWM\_AUX\_FUNC parameter where FUNC1-4 are the 4 pwm outputs. To assign a PWM output to a mapping, just find the number of the PWM output, and the associated PWM\_AUX\_FUNC and assign it to the desired mapping. ie, ie, if you use RC AUX 1, it should use Dial 2 to control the PWM output.
{% endtab %}
{% tab title="1.9.2 and earlier" %}
{% hint style="info" %}
PWM outputs were not enabled on aircraft with the Doodle Radio until 2.0.19
{% endhint %}
In AMC, select the output pins by navigating to Menu > Vehicle Setup > Parameters. Possible outputs are:
| IO board label | Parameter name |
| -------------- | -------------- |
| 1 | RC\_MAP\_AUX1 |
| 2 | RC\_MAP\_AUX2 |
| 3 | RC\_MAP\_AUX3 |
| 4 | RC\_MAP\_FLAPS |
For each output, select an input source channel (i.e. [Herelink hardware button](/astro/other-user-manuals/ecosystem/components/pilot-handsets.md#hardware-controls) you will push to trigger a change in PWM).
| Herelink | Channel |
| ------------- | ------- |
| Wheel | 5 |
| Button D | 10 |
| {% endtab %} | |
| {% endtabs %} | |
PWM output values (e.g. 1100 us) are controlled by these parameters (read more in the [PX4 Parameter Reference](https://dev.px4.io/master/en/advanced/parameter_reference.html)).
| Parameter | Function |
| --------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------- |
| PWM\_AUX\_DIS1 | PWM output when autopilot is not armed. When set to -1 the value for PWM\_AUX\_DISARMED will be used. a similar parameter is availabel for each channel |
| PWM\_AUX\_MIN1 | Minimum PWM pulse for this output. When set to -1 the value for PWM\_AUX\_MIN will be used. |
| PWM\_AUX\_MAX1 | Maximum PWM pulse for this output. When set to -1 the value for PWM\_AUX\_MAX will be used. |
| PWM\_AUX\_REV1 | Invert direction. |
| PWM\_AUX\_FAIL1 | PWM output if autopilot is in failsafe mode. When set to -1 the value is set automatically depending if the actuator is a motor (900us) or a servo (1500us) |
### **CAN**
Connector: JST GH 4-pin
### **Console pinout**
Console is a special serial (UART) port that is useful for troubleshooting applications running on the IMX8 processor inside Astro.
Connector: JST GH 6-pin
### **Ethernet**
Connector: JST GH 6-pin
### **Bind Button**
The Bind Button is used in the binding/pairing process for Astros equipped with a Doodle Labs radio. See [Doodle Binding / Pairing Guide](https://docs.freeflysystems.com/ecosystem/controller/pilot-pro/operating-handbook/radio-modules/doodle-labs-radio-module/doodle-binding-pairing) for more information.
### Battery V
Connector: XT-30
* Battery Voltage: 18 - 25.2 VDC
* Continuous current: 4.5 A (overcurrent protection set to approximately 5 A)
The XT-30 connector provides direct access to the raw battery output. Please note that the overcurrent protection is set to trip around 5 A, though variations may occur, with testing showing cutoff points between 4.7 and 5.3 A. We recommend keeping the load under 4.5 A to avoid triggering the protection circuit.
**Important Notes**:
* If you are not using a gimbal, you can draw up to 4.5 A through the XT-30 connector.
* If you have a gimbal attached, which typically draws about 1 A, you’ll need to limit the remaining load on the XT-30 to 3.5 - 4 A.
* The circuit responds within a few milliseconds, so any large inrush currents may activate the overcurrent protection.
{% hint style="info" %}
In order for the XT30 to behave as expected, the Herelink needs to be powered on and in communication with Astro.
{% endhint %}
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